Annual/Termination Reports:

[01/18/2010] [01/25/2011] [02/08/2012] [04/03/2013]

Report Information

Participants

Barnes, Dave, Univ. of Alaska, Fairbanks, AK; Berli, Markus, Desert Research Institute DRI, Las Vegas, NV; Chief, Karletta, Desert Research Institute DRI, Las Vegas, NV; Flury, Markus, Washington State University; Ghezzehei, Teamrat, Univ. California, Merced, CA; Hopmans, Jan, Univ. of California, Davis, CA; Horton, Bob, Iowa State University, Ames, IA; Jacobsen, Jeff (Advisor W-2188), Montana State University, Bozeman, MT; Jones, Scott, Utah State University, Logan, UT; Kamai, Tamir, Univ. of California, Davis, CA; Kelleners, Thijs, Univ. of Wyoming, Laramie, WY; Kluitenberg, Gerard, Kansas State University, Manhattan, KS; Knighton, Raymond, USDA, Washington, DC; Nielsen, Don, Univ. of California, Davis, CA; Schaap, Marcel,Univ. of Arizona, Tucson, AZ; Schwartz, Robert, USDA-ARS, Bushland, TX; Shukla, Manoj (new member), New Mexico State Univ., Las Cruces, NM; Simunek, Jirka, Univ. of California, Riverside, CA; Tuller, Markus, Univ. of Arizona, Tucson, AZ; Twarakavi, Navin (new member), Auburn Univ., Auburn, AL; Vaz, Carlos, EMBRAPA, Sao Carlos, Brazil; Warrick, Art, Univ. of Arizona, Tucson, AZ; Wendroth, Ole, Univ. of Kentucky, Lexington, KY; Wierenga, Peter, University of Arizona, Tucson, AZ; Young, Michael, Desert Research Institute DRI, Las Vegas, NV; Zhu, Jianting (Julian), Desert Research Institute DRI, Las Vegas, NV; Guests: Luigi, Donat-Pierre, Desert Research Institute DRI, Las Vegas, NV; Mahesh Gautam, Desert Research Institute DRI, Las Vegas, NV; Sakai, Masaru, Utah State University, Logan, UT; Meyer, William, Desert Research Institute DRI, Las Vegas, NV.

Brief Summary of Minutes

MONDAY, JANUARY 4, 2010
10:00 am: Markus Tuller, W2188 chair, welcomed the participants and acknowledged Michael Young and Karletta Chief for their help with local arrangements. Jeff Jacobsen gave a brief introduction of his role and welcomed the group.
10:30 am: Karletta Chief
Karletta addressed assessment of hydraulic properties in a Sonoran Desert using air permeability measurements. Saturated hydraulic conductivity measurements were compared to air permeability measurements as well as with an empirical relationship developed by Loll et al. (1999) developed for structureless agricultural soils.
11:00 am: Julian Zhu
Mahesh Gautam, working with Julian, spoke on, A Modified Artificial Neural Network Pedotransfer function for soil hydraulic properties. The study addressed some problems with Pedotransfer function formulation and issues associated with database selection and variability.
Julian Zhu spoke on, Modeling of ET partitioning in Arid Environments-Scale Effects. Their objective was to examine scale effects of ET partitioning simulations in relation to shrub coverage structure and it interaction with hydraulic properties in arid environments. Julian also addressed the topic, Evapotranspiration estimates from ground water level fluctuations in a riparian zone. Data collected from wells at varying distance from a river were compared to river stage measurements and correlations were developed.
11:30 am: Dave Barnes
David is part of the Water and Environmental Research Center in the Department of Civil and Environmental Engineering, Univ. of Alaska-Fairbanks. He addressed environmental problems in the Arctic. Gravel pads are a necessity in dealing with the instability of permafrost but hydraulic and gaseous transport in these pads can be a hazard and little is known regarding these processes under the extreme arctic environment. David is also working to determine safe application of herbicides to roadways in Alaska, where a longer half-life of herbicides results from the extended cold climate.
1:00 pm: Navin Twarakavi
Navin is looking at hydrogen-soil mixtures to improve water holding properties of golf course porous media. He measured the swelling, water holding and hydraulic characteristics of treated soils. Hydrogel cross-link ratio can be engineered to adjust swelling and was found to be a management strategy for optimizing the hydrogel impact on soil properties.
1:30 pm: Gerard Kluitenberg
Gerard addressed the Effect of probe deflection on dual-probe heat pulse thermal conductivity measurements. Theoretical independence of the thermal conductivity on probe spacing changes of about 15% shown to be a valid assumption using measurements in dry and saturated sand and water.
2:00 pm: Tamir Kamai
Tamir discussed understanding estimation bias and offset of heat pulse probes. Numerical simulations demonstrated the impact of the thermistor stainless steel on the thermal transport and heat flux. Human body water content determination using a button probe was evaluated on human skin and meat products.
2:30 pm: Jan Hopmans
AddressedCritical Zone Observatory Snowline Processes in the Southern Sierra Nevada. The CZO is a collaboration with UC-Davis, -Merced, -Santa Barbara, -Berkeley, -Irvine, the University of Nevada and USFS-Fresno. The UC Davis group is charged with instrumenting the subsurface. A large tree was selected as the initial site with a wheel spoke design for sensor layout and installation. Instrumentation includes water content, temperature, matric potential, and tree sap flux sensors.
3:30 pm: Robert Horton
Bob reported on advances in their work on soil water evaporation estimates using a novel 11-needle heat pulse probe. Another project is looking at soil carbon dioxide emissions measured in a collaborative study in Corn. Subsurface CO2 concentration and chamber-based surface emission measurements were carried out at different locations within the corn rows both including and excluding roots. Other topics they are addressing include sorption of Estrogen compounds to soil sand colloids, scale dependence of intragranular porosity, tortuosity and diffusivity, and soil wetability effects on coupled heat and water transfer.
4:00 pm: Masaru Sakai
Masaru carried out simulations of subsurface evaporation using Hydrus 1D to evaluate components of the Heat Pulse Probe (HPP) method described by Heitman and Horton (2008). Estimates in three differently textured soils indicated the method accounts for ~70-80% of the total energy. Bob Horton suggested the 20- 30% energy in the form of liquid water flux seemed high given the significant energy associated with the latent heat of vaporization. Corrections for the liquid water flux component were suggested to be missing in the HPP method and closer spacing between temperature measurements theoretically improved accounting for evaporation occurring near the surface.

TUESDAY, JANUARY 5, 2010
8:00am Business Meeting
Markus Tuller (chair) called the business meeting to order at 8:00 am and requested approval of the 2008 activity report and 2009 meeting minutes. The group unanimously approved the activity report for the year 2008 and 2009 meeting minutes.
Markus Tuller nominated Manoj Shukla (New Mexico State University) and Jirka Simunek nominated Navin Twarakavi (Auburn University). After Manoj and Navin introduced themselves, the committee unanimously approved their membership.
The committee nominated two candidates for the coming year's secretary: Marcel Schaap (Univ. Arizona) and Thijs Kelleners (Univ. Wyoming). After a vote, Thijs was selected by the committee to serve as the 2011 secretary and he accepted the assignment.
Markus reminded us about last year's proposed changes to the W1188 (now 2188)webpage to create a platform for information exchange and submission of activity reports. Despite Frank Casey's work in setting up the site, no one has used it. A discussion about next year's meeting included the follow up suggestion from 2009 to hold a meeting in Hawaii. With an informal vote 12 were in favor of Hawaii, 2 voted for Las Vegas and the remaining attendees were decidedly undecided.
9:00 am: Jeff Jacobsen presentation
Commendation was given on the new project proposal and to Markus Tuller for getting past members to be maintained on the NIMS website list of participants. The W2188 reporting format for individual participants was modified to fit the reporting within NIMS. Jeff emphasized the need to focus our outcomes and impact reporting on the original proposal. Multi-state research award is granted yearly ($15,000), $5000 goes to support travel for the Chair, one member and the administrative advisor to attend the annual meeting where the award is made. The other $10,000 goes to the group for supporting meetings and other activities they choose. Deadline is February 26th for this grant proposal. Mike Young, Markus Tuller, and Scott Jones offered to work on this proposal. Questions regarding W2188 State Experiment Station travel funds were brought up with the finding from the group that each state differs in how they administer the funding, including travel and salary. Hatch funding typically pays salaries for the most part freeing up state funding for other activities. Don suggested Jeff look into the possibility of getting additional funds for the W2188 group from the experiment station directors. Bob asked about our negotiating power for how to use the Hatch funds. Jeff said the experiment station director decides how to use those funds.
9:30 am: Raymond Knighton presentation
USDA changes are coming this year. October 2009 a new organization kicked in which is now named the National Institute for Food and Agriculture (NIFA). Within NIFA the Agriculture and Food Research Initiative (AFRI) will continue to fund research, but with a different approach to the size of awards and target areas. Political appointees are taking charge and reorganizing the former USDA under priority areas, including climate change, global food security, etc. Four mini-institutes within USDA are organized to work on topical issues. The Farm Bill spelled out the reorganization but the mission is still the same. Past funds were not tied to specific topics, new funds are now tied to high priority societal needs as determined by the new administration. New RFA will come out in February and will be directed to these new areas within which we will need to search for funding relating to soil physics and related issues. Topical areas are developed based on their Focus, Scale and Impact. Rather than disciplinary type of research, the funding will be aimed at targeted topical issues. Larger awards will be aimed at producing greater impacts toward the societal issues of concern. Foundational research programs will fund basic research that relates to the big picture topics. Bob Horton voiced an inspiring summary of the opportunities that this new program provides for those that are willing to be open-minded and collaborative under topics such as global climate change. Mike Young commented that with some of this in mind, the new project proposal was developed toward W2188 becoming more interdisciplinary in our research interests. Ray suggested we visit NIFA's URL www.NIFA.usda.gov for funding RFA announcements.
10:30 am: Don Nielsen
We were delighted to hear from Don Nielsen who has been the strongest and longest attendee/supporter of W2188 in the Earth's history. Don discussed failures and opportunitiesalong his career path. Many ideas were shared regarding unfinished work and potential opportunities to renew some of those experiments. Novel fixtures for performing experimental work were described and Don's PowerPoint presentation was distributed after the meeting to all W2188 members.
11:00 am: Art Warrick
Art addressed infiltration from 2- and 3-D sources using combined 1-D coupled with an edge term. Sources examined included disk, strip, furrow and both lined and unlined boreholes. Neurodrip is an analytical neural network model written in excel by Naftali Lazarovitch. Neurodrip is available at: http://bidr.bgu.ac.il/bidr/karusela/Neurodrip.mht
11:30: Scott Jones
Scott described progress on the Penta-needle heat pulse probe which is an SDI-12 sensor that ouputs thermal diffusivity, thermal conductivity and heat velocity in x and y directions from which water flux and heat capacity can be resolved. He also presented some comparisons of surface CO2 chamber flux determinations compared to subsurface gradient-based estimates of CO2 flux. A summary of EM sensor comparison work was also summarized.
1:00 pm: Markus Tuller
Markus summarized a number of topics including segmentation of X-ray CT data to provide quantitative pore space analysis and fluid dynamic modeling. He also described geophysical characterization of mine tailings as a first step to revegetation of an inactive tailings pond. Other work included optimizing greenhouse irrigation in artificial substrates made of recycled glass and organic waste products.
1:30 pm: Thijs Kelleners
Work in Wyoming includes measurement and modeling of Cow2 production and transport in rangeland soils. Thijs described his research site and installation of various sensors for water content and matric potential, temperature, CO2 and O2. Thijs' hydrology model is being enhanced to account for CO2 based on work of Simunek and Suarez (1993) and will be calibrated using some of the measured data.
2:00 pm: Michael Young
Michael discussed work at DRI dealing with near surface water dynamics in desert soils with a focus on the differences shrubs make in soil water dynamics. He mentioned the controversy about whether deserts serve as significant carbon sinks. Additional work in the desert looks at the deeper water and its role in sustaining life at micro-site levels, which develop from vegetation structure.
2:30 pm: Robert Schwartz
Evaluated permittivity response to bulk EC using column displacement experiments as a means of determining the suitability of effective frequency approximation for TDR measurements. Tillage effects on water redistribution and bare soil evaporation throughout a season were evaluated. Evaporation was monitored using TDR lysimeters in a deficit irrigation study.
3:30 pm: Markus Flury
Discussed colloid fate and transport in the unsaturated zone. Focused on colloid attachment to the liquid-gas interface. Considered colloid breakthrough from unsaturated columns using high ionic strength solution. Other work includes water balance and conservation in dryland agriculture as well as water erosion and WEPP modeling of erosion processes. A National Needs Fellowship Program has been established at WSU.
4:00 pm: Ole Wendroth
Addressed Field scale bromide transport as a function of rainfall intensity and application time delayand spatial soil processes and crop nitrogen response across the landscape. Statistical methods were employed to determine effects on transport and the scale effects on parameters within heterogeneous field designs.
4:30 pm: Jirka Simunek
Jirka reviewed recent applications and modification to the HYDRUS Software package. Advanced have been made in biogeochemical modeling using the combination of HYDRUS-1D and PHREEQC (HP1). A GUI interface was added to HYDRUS 1D to include the PHREEQC inputs. Advances were also made in HYDRUS 1D for addressing preferential flow scenarios and for transport of various contaminants that may undergo degradation, sorption and other complex transformations. A Professional level of HYDRUS 2/3D will be released soon to include generation of general 3D geometries, the import of initial conditions and material properties from previous projects. A parallelized version is also available for faster processing of simulations. All of this and more is presented on the HYDRUS website.
http://www.pc-progress.com/en/Default.aspx.

WEDNESDAY, JANUARY 6, 2010
8:00 am: Group Discussion about Impacts
The question was asked about what the W2188 group's most significant impacts were. Reponses included, students trained and graduated and postdocs trained. These should be reported along with our other impacts. Jirka Simunek, M. Sejna and M.Th. van Genuchten's ongoing contributions to W2188 are among the most significant. They have developed a number of simulation programs addressing topics within and related to the objectives of W2188 and prior projects. The website summarizes many of these contributions of not only Jirka's group, but also of the many collaborators who used Hydrus and other software. These collaborations have significantly furthered both the refinement of the programs in addition to the breadth of topics addressed by software developed by Simunek et al. These contributions are highlighted in: The significant number of publications from many within W2188 and beyond on the PC-Progress website http://www.pc-progress.com/en/Default.aspx?h1d-references. Special issues within Vadose Zone Journal have been organized. The list of member-authored publications reported annually. Instrument and sensor developments including the Nitrate sensor (patent pending) from Hopmans group as well as the evaporation method using the heat pulse approach from Horton's group. Improvements in CO2 sensing techniques were also pointed out, which will likely be used in policy development such as Cap and Trade legislation. Environmental work in Alaska addressing health hazards from historical extraction practices and providing data for development of regulations aimed at protecting public health hold promise for direct outcomes from the research.
8:30 am: Group Discussion about the 2011 Meeting
At the 2009 meeting, Jan Hopmans suggested a future meeting in Hawaii. He proposed to invite Ali Fares (Univ. of Hawaii) to join the W2188 group to have a local organizer. Markus and Scott contacted Ali and he expressed interest in hosting a future meeting. An informal poll about next year's location was conducted during the meeting and showed 12 in favor of a meeting in Hawaii, 2 in favor of returning to Las Vegas and the remainder abstaining. An email poll will be taken after the meeting to determine by popular vote where to meet in 2011 with the option of considering Hawaii beyond 2011 if we meet in Las Vegas. Don Nielsen and Bob Horton provided information based on their experience with a past meeting held in Hawaii, naming colleagues there who could address our group and help with local arrangements.
Jeff Jacobsen offered to contribute travel funds for invited speaker for the 2011 meeting and said a meeting location and date need to be determined over the next several months. Suggestion to decide on a theme for the next year's meeting based on the project proposal and invite speaker addressing that theme. Ray suggested looking at the new RFA's coming out when deciding on a theme. Markus, Scott, Michael and Ole volunteered to develop a 3-page proposal for grants that could provide funding for the working group to develop funding to support the travel for speakers, etc. Gerard suggested devoting time at next year's meeting to develop this further. Ray suggested that there will be novel opportunities requiring creative thinking about how to interact with outside groups. Don commented that this group focused its future meetings and preserved the interactions that are absent from other meetings where there is less interaction and more focus on topics, outside speakers and topics. He noted (sitting on the back row) that we are too distracted (web access) at this meeting to focus on the important and rare interactions that historically have happened at W188 between individuals and the group. It was suggested limiting wireless access during speaking sessions at future meetings.
9:00 am: Marcel Schaap
Marcel is looking into how we can most effectively generate hydraulic property field for vadose zone transport modeling. Pedotransfer functions (Rosetta) were used to infer hydraulic properties at the Hanford Site. A modification to Rosetta was made for the coarse soils at the Hanford site.
9:30 am: Teamrat Ghezzehei
Teamrat (pronounced Tamrat) addressed permeability evolution by precipitates and formation of aggregates by wetting-drying processes. The question was asked, What is the macroscopic implication of pore-scale heterogeneities caused by precipitation-dissolution processesTwo- and Three-D physically-based modeling approaches were characterized with 2-D yielding similar results to 3-D for a range of interest. Significant impacts on permeability were demonstrated using pore-scale heterogeneities approximating the growth of crystals and other pore-level geometry change. Aggregate stability experiments were carried out to simulate the effects of root exudates.
10:00 am Markus Berli
Markus addressed, Unraveling rhizosphere physics using X-ray Microtomography. Effect of soil compaction near roots was discussed and tools for studying these changes were considered. Artificial root, a small balloon, was inflated to mimic the compression of soil particles. Further work is being carried out to quantify changes in the pore size distribution.
10:30 am Manoj Shukla
Manoj reported on spatial variability of soil physical (including thermal) and chemical properties of desert soils irrigated with treated industrial effluent. Another project deals with short and long-term soil water depletion/extraction patterns in two irrigated pecan orchards using a variety of instruments. Another project dealt with numerical modeling of coupled water and heat transport in a sandy loam field soil.

Respectfully submitted,

Scott B. Jones
2010 W2188 Secretary

Accomplishments

Short-term Outcomes<br /> Alaska found a strong correlation between concentrations of volatile contaminants in the ambient air of buildings that have been impacted by releases of these substances and temperature. This finding may impact environmental regulations related to vapor intrusion and public health. We have also shown for the first time the temporal change of pad pore-water gradient in Arctic gravel pads used for infrastructure foundations. This finding will aid both owners of these gravel pads and environmental regulators as they develop remediation strategies and regulations related to these structures. In addition, we have found that herbicides in subarctic environments attenuate at the same rate as has been found in more temperate environments, however the persistence of herbicides applied in the subarctic may be comparatively longer than in temperate environments. Arizona developed a new procedure for correction of intensity bias in X-Ray CT data that not only benefits the soil science community, but is also applicable for medical imaging and material science CT applications. We also showed that ERI and EMI techniques can be successfully applied to highly adverse engineered environments (i.e. mine tailings). Iowa compared surface cumulative evaporation from Bowen-ratio method and subsurface cumulative evaporations of soil depths of 3 mm, 9 mm, 15 mm and 21 mm from heat-pulse method, which were very consistent over 2-3 week time periods in 2007 and 2008. The heat-pulse probes appeared to accurately estimate in situ subsurface evaporation fluxes. High-connectivity results were indistinguishable from Cranks analytical solution. Low-connectivity results were consistent with observations reported in the literature, with solute released at early times more quickly than indicated by the analytical solution, and more slowly at late times. Water repellency was found to affect coupled heat and water transfer in soil. The net movement of soil moisture toward the cool end of the columns was greater in the wettable soils than in the hydrophobic soils. Soil temperature transients were greater in the wettable soils than in the hydrophobic soils. Kentucky developed new tools, devices, analytical methods and capabilities to quantify and monitor movement of agricultural contaminants and other materials from the vadose zone to ground water and to the atmosphere. Periodic variation patterns of irrigation treatments were used to study bromide leaching behavior under different boundary conditions at the field scale, while being able to quantify the local representation of bromide concentration measurements. Active and passive remote sensing crop scanners were used to determine spatial zones of nitrogen deficiency and soil-based crop variation early in the season. Spatially varying crop response to nitrogen can be evaluated and assuming a unique nitrogen response in a farmers field is not necessary with this approach. These techniques should lead to improved protection of soil and water resources and sustainability associated with energy production, water/irrigation management and mineral extraction activities. Minnesota developed groundwater recharge estimate atlases, which will be of use in regional water resource planning for the allocation of water resources to meet human needs in competition with the need to sustain ecological services. Preliminary results from this study were used by the Minnesota Environmental Quality Board (MnEQB) in conducting an assessment of the status of freshwater resources within the state. It is expected that as new results are developed, the MnEQB will use the updated information to revise these assessments. Nevada developed an approach that enables the application of effective soil hydraulic properties to large scale transient infiltration problems in a landscape with horizontally heterogeneous soil hydraulic properties. A two-layer one-dimensional steady-state conceptual model was established that can be used to investigate water seepage loss reduction by applying high molecular weight, anionic, linear polyacrylamide (PAM). We also developed a new maximum likelihood approach to estimate the probability density functions (PDFs) of water retention parameters for situations common in field-scaling modeling where core samples are sparse and prior PDFs of the parameters are unknown. We also showed that soil-root interfaces can be imaged using CMT and changes in macro-pore volume of the rhizosphere can be quantified employing numerical image analysis. A new method to estimate Green-Ampt infiltration parameters was developed based on soil moisture measurements and cumulative infiltration curves obtained during rainfall simulator tests. This parameter optimization procedure optimized results for the hydraulic conductivity and potential at the wetting front. The approach worked well for ideal, measured infiltration curves. North Dakota State University carried out field lysimeter studies where hormones were detected at frequencies and levels that indicated antecedent levels were present and that sources besides the applied manures contributed to the hormones in the soil. Hypotheses were developed to explain why hormones, which readily degrade and bind strongly to soil, are detected in the subsurface environment. Information from a Hg survey in ND will establish baseline and distribution of total Hg in North Dakota soils. Cleaning tile drainage lines of Mn-reducing biofilm did not have a long-term effect on improving the tile drainage (few months), which then returned to original levels before cleaning. The cleaning may even have a negative effect in which the tile lines are damaged. Turned manure piles had reduced nutrients, but hormones levels were not affected, suggesting composting is not effective in reducing hormones. Adding soil organic amendments, improving seedbed structure, adding topsoil, and removing coarse fragments where some recommendations that came from the restored oil-road soil study. These practices may help improve the establishment of plant species indicative of natural areas. Oklahomas project has provided research experience and mentoring for three undergraduate students. Soil samples were collected at 30 Mesonet sites and laboratory analysis was initiated. Preliminary data on soil moisture and plant available water (PAW) validated the methods used and were used as the foundation for a grant proposal to support the full project. Oregon postulated a new mechanistic model for the process controlling evaporation from saline porous media. This mechanism is in process of further evaluation. Work is performed at the laboratory and field scales permitting assessment of the saline evaporative mechanism at a spatial and temporal scale that is appropriate for addressing resource management questions. Completion of this project will benefit not only the soil science community, but is applicable in many areas of material sciences including construction, engineering, and protection of architectural monuments. Texas (A&M) has adopted a multi-facet approach to deriving large-scale soil hydraulic properties including: (1) a bottom-up approach, where larger-scale effective parameters are calculated by aggregating point-scale in situ hydraulic property measurements, (2) a top-down approach, where effective soil hydraulic parameters are estimated by inverse modeling using remotely sensed soil moisture measurements, and (3) an artificial neural network approach, where effective soil hydraulic parameters were estimated by exploiting the correlations with soil texture, topographic attributes, and vegetation characteristics at multiple spatial resolutions. UC-Davis continued development of multi-functional soil sensors for soil moisture and nitrate, including various proven prototypes that may lead to easy-to-use and low-cost soil moisture sensors based on heat pulse concept. Deployment and testing of wireless soil moisture network in remote forested ecosystem occurred. New root water and nutrient uptake models that allow for compensated water uptake and passive and active nutrient root uptake were developed. The initial findings of this NSF project were instrumental in obtaining a new grant from BARD that will also investigate root water and nutrient uptake mechanisms, using the probe designs developed in this project. UC-Riverside developed a new analytical method that can simultaneously determine multiple trace organic compounds in wastewater and in soils. We developed a method to measure solute diffusion coefficients as a function of water content in soils. The set of data will be very useful for evaluating the solute diffusivity models. US Salinity Lab researched Cryptosporidium Parvum oocysts, which have caused major water-borne disease outbreaks in the United States. Two major findings were observed: (i) oocyst retention was enhanced in low velocity regions near grain-grain contacts when chemical conditions were unfavorable for oocyst-sand interactions; and (ii) reversible oocyst retention occurred under conditions that were favorable for oocyst-sand interaction due to the presence of macromolecules on the surface of the oocysts. This study helps us to better understand mechanisms that control the fate of oocysts in groundwater environments, and will be of use to scientists, engineers, and regulators who are concerned with protecting water quality. Packed column and micromodel transport studies were conducted to gain insight on mechanisms of colloid retention and release during transients in solution chemistry. When the ionic strength (IS) of the eluting solution was reduced, a sharp pulse of released colloids occurred. When the eluting fluid IS was reduced to deionized water the final retention locations occurred near grain-grain contacts and colloid aggregation was sometimes observed. The final amount of colloid retention was demonstrated to be dependent on the porous media shape, the colloid size, and on the initial deposition IS. Utah continued to make advances in dielectric theory and measurements for water content determination in soils and porous media. A temperature control chamber was developed from a wine cooler for managing experiment temperature and humidity based on sensor controls. Electromagnetic induction measurements are continuing to be used to assess soil properties related to Aspen decline in the Western US. Washington's work on colloidal processes in the vadose zone helps to better design and manages contaminants at the US Nuclear Hanford Reservation. It is part of a larger effort of the US Department of Energy to clean-up the Hanford Site. Our work on water balance and seed-zone water helps farmers to adopt optimal farming procedures to minimize costs and maximize environmental protection. We have made a major contribution to continually developing and improving the USDA's Water Erosion Prediction Project (WEPP) model. WEPP is widely recognized as a leading technology for water erosion prediction Wyoming published a cost-effective calibration method for Hydra soil water content sensors. These sensors are used throughout the US as part of the NRCS Soil Climate Analysis Network.<br /> <br /> Ouputs<br /> W2188 participants contributed 137 publications including 3 book chapters in addition to delivering 86 presentations. Iowa developed measurement approaches for soil-water evaporation and soil-carbon dioxide fluxes at different crop management positions. Heat-pulse probes were installed at multiple depths to measure the dynamics of subsurface soil-water evaporation with time and depth. Independent estimates of surface evaporation, transpiration in the canopy and evapotranspiration above the canopy were obtained from micro-lysimeters, micro-Bowen ratio, stem flow and eddy covariance methods, respectively. Estrogenic hormones in soil have become an issue of concern with regards to agricultural manure use. We have performed the first of three stages of experiments investigating the fate and transport of two hormones (estradiol E2 and estrone E1). We examined the so-called slow sorption phenomenon, in which release of a pollutant is increasingly difficult as its residence time in the soil increases. Some research has suggested that the uptake and release are diffusion-limited at the scale of the individual grain. Noting that intragranular pore space is likely to be poorly connected, we used a pore network model to examine intragranular accessible porosity, tortuosity, and diffusivity as functions of grain size and intragranular pore connectivity. We examined the impact of biochar applications to soil on plant available water (PAW). We studied sand typical of golf course greens, and a high organic matter loam soil. In each case the soil water holding capacity and the plant available water increased as the biochar fraction increased. We have established a new research site near Ames for studying biofuel production impacts on soil and water. Kentucky generated new information on mass and energy transport processes in soils at spatial and temporal scales appropriate for effective resource management. Minnesota generated atlases of groundwater recharge at various spatial scales (statewide, regional, county) and a water resources database that can be queried to readily determine the renewable flux of freshwater within a given area. NDSU applied manure from a static manure pile, raw manure, and storage pond slurry to plots in which subsurface waters were sampled using lysimeters (0.6 m deep) and wells (2 m deep). Presentations were provided to Congress through the Coalition of National Science Foundation conference. Additionally, two book chapters were written regarding the general issue of hormones and animal agriculture and how hormones are transported in the environment. Electricity generation through coal combustion can potentially deposit Hg throughout ND. The distribution of Mercury (Hg) across ND was measured using surface soils. Also, floodwaters from a 500-year event were evaluated for water quality and Hg concentrations, potentially from snow deposition. Research was disseminated in two presentations on the distributions of Hg in ND and on floodwater quality at the SSSA international annual meetings. The effects of a bacterial biofilm on the drainage efficiency and nitrate reduction in subsurface tile drainage were investigated. In Situ Mesocosm to measure denitrification rates in the aquifer sediment were installed. Also, the model, DRAINMOD, and several tracer studies were used to measure lateral water transfer into the tile drainage lines before and after they were cleaned. A M.S. thesis was completed from this research looking at how the biofilm affects the tile line hydraulic efficiency. The effect of manure composting was also evaluated using turned and unturned manure piles. Composting may be a potential method of reducing hormone concentrations in manures. Soil physical and chemical properties were measured in combination with plant surveys of areas restored after oil roads were abandoned. Research was presented to the National Forest Service to advise them on road restoration, and a M.S. thesis was completed from this project. Oklahoma was funded on a monitoring proposal to develop a system for tracking plant available soil moisture based on the Oklahoma Mesonet, submitted to Oklahoma Water Resources Research Institute. A collaborative effort led to the selection of the Marena Mesonet site as the site of the SMAP In Situ Instrument Test Bed. This test bed will inter-compare the world's leading soil moisture sensing technologies at one location. This involves collaboration with USDA-ARS Remote Sensing Laboratory, the Oklahoma Climatological Survey, and many others. UC-Davis developed a patent, Tuli, A., J.W. Hopmans, T. Kamai, and B.D. Shaw. 2009. Patent Application Publication. In-situ soil nitrate ion concentration sensor. US patent application serial no. 12/267,895. Pub. No.: US2009/0166520 A1. We also developed and taught for the second time a new course in Environmental Monitoring. This course was co-taught by one of the postdocs hired for this project. The environmental monitoring course includes sections on sensors and wireless techniques. UC-Riverside generated a UC Division of Agriculture and Natural Resources peer-reviewed technical bulletin on safe application of reclaimed wastewater in southwest states was published and distributed to various audiences. Co-organized two conferences (2009 biannual groundwater conference, and Salinity and Drainage/California Groundwater Association Joint conference). US Salnity Lab Results from our work with colloid and chemical transport have important implications for quantifying the evolution of colloid retention in soil over time, for determining the potential importance of transients in suspension concentration on colloid fate, and for predicting long-term colloid transport as well as the importance of chemical interactions on immobilized colloids. Washington generated new information on colloid mobilization and transport processes in the vadose zone, both soils and unsaturated sediments, at the microscale. Fundamental knowledge of microscale processes is a prerequisite for understanding field-scale behavior of colloids. We are developing a management model to predict seed-zone water content in the dry-land Pacific Northwest, providing farmers a tool to decide what management strategy may be best to minimize costs and maximize environmental protection. The improvements on the WEPP model will result in a new release in 2010. Wyoming completed a distributed soil water flow and heat transport model to calculate runoff generation in snow-dominated mountainous areas. Model results for a small catchment near Boise, ID show that only 11 to 16 % of the annual incoming precipitation is transformed into streamflow. Finalized a study on the dielectric properties of soils at 50 MHz. Results show that energy losses due to electrical conductivity and dielectric relaxation are both significant at this low frequency. Completed a study on the fate of arsenic in coalbed methane water disposal ponds. Results for an unlined pond in Wyomings Powder River Basin showed that the arsenic remains in the pond and does not leach to the underlying groundwater because of low infiltration rates brought about by the sodic nature of the pond water. Journal papers describing these outcomes have been submitted to VZJ, SSSAJ, and JEQ, respectively.<br /> <br /> Activities<br /> Arizona (Tuller) served as the W-2188 chair and assisted with developing the W-1188 renewal proposal writing committee chaired by Michael Young (DRI), and contributed to the organization of the 2009 (Tucson) and 2010 (Las Vegas) annual meetings. In addition, we were involved in the following collaborative research projects with other W-2188 members and the USDA: (1) physicochemical controls on initiation and evolution of desiccation cracks in bentonite-sand liners by means of X-ray CT and stochastic modeling in collaboration with Teamrat Ghezzehei (UC Merced); (2) liquid behavior in porous materials under reduced gravity in collaboration with Scott Jones (USU) and Dani Or (ETH); (3) geophysical characterization of inactive mine tailings in collaboration with Scott Jones (USU) and Robert Heinse (UI); and (4) pathogen transport in macroporous soils in collaboration with Yakov Pachepsky (USDA) and Andrey Guber (USDA). Schaap presented several invited talks at research institutions in Germany. Minnesota has been proactive in presenting results in a number of venues to promote the use of the methodology and associated results. A webpage has been developed that describes the method and presents the results. https://wiki.umn.edu/view/Water_Sustainability. Nevada organized several technical sessions at conferences, Smith, J., and M. H. Young. 2009. co-conveners of Environmental Vadose Zone Hydrology, 2009 AGU Fall Meetings, December 14-18, 2009, San Francisco, CA; Young, M. H., and J. Zhu. 2009. co-conveners of Integrating Soil Physics into the Science of a Changing World, 2009 ASA-CSSA-SSSA International Annual Meetings, November 1-5, 2009, Pittsburgh, PA; Zhu, J., M. H. Young, and D. Sun. 2009. co-conveners of Landscapes in Semiarid and Arid Environments: A Hydrological and Ecological Perspective, 2009 AGU Fall Meetings, December 14-18, 2009, San Francisco, CA. Oregon participated in fieldwork at two different sites where natural fractures occur, one in soil and one in rock. Both sites are located in semi-arid environments typical of irrigated agriculture. Fieldwork focused on testing the existence of mechanisms and measuring the extent to which these phenomena exist in real field conditions. Laboratory work focused on quantifying field observations and testing of hypothesis. Field and laboratory work aimed at investigating the role of internal boundaries on evaporation and salt deposition processes. Additional activities included teaching graduate soil physics and undergraduate hydrology courses, and mentoring or co-mentoring of four graduate students working on this project. Texas (Bushland) led studies in the following projects: (a) a collaborative study with Kansas State University to monitor tillage effects on near-surface water contents in wheat-sorghum-fallow rotation at two locations: Tribune, KS and Bushland, TX. An economic analysis of the alternative management strategies for both locations is underway; (b) A study assessing the influence of deficit irrigation strategies on the water use efficiency (WUE) of grain sorghum and the associated temporo-spatial dynamics of root-water uptake. Early season soil water use immediately following irrigation events were evaluated using TDR and microlysimeters instrumented with vertical TDR probes. (c) Tillage effects on water balance and near soil surface evaporation and evaluated the effects of sweep tillage (ST) on near surface soil water dynamics as compared with an untilled (UT) soil during a 7 month period. UC-Davis participates in a Critical Zone Observatory (CZO), which has led to much new collaboration with colleagues at various academic institutions, including in hydrology, ecology and climate science. We also served as a member of a 6-person team that is writing a position paper on the need of improved guidelines for managing soil salinity and crop salt tolerance under micro-irrigation conditions. UC-Riverside is collaborating with UC-Davis, US Salinity Laboratory and International Center of Agricultural Research for Dry Area in evaluating salinity management and leaching fraction; Collaborating with University of Arizona and other southwest states/Pacific islands on wastewater reuse projects. Served as a member of a 6-person team that is writing a position paper on the need of improved guidelines for managing soil salinity and crop salt tolerance under micro-irrigation conditions. US Salinity Lab completed work with collaborators from Pakistan and China on multiple research projects focusing on irrigation and water management problems faced in developing countries. The research project's applied modeling technology and expertise developed under W-1188 to water management problems faced by farmers in rural areas. Additionally, models developed as part of W1188 were used to evaluate groundwater recharge in a drought-stricken agricultural region of southeast Spain that has been identified by the United Nations Food and Agricultural Organization as possibly being a leading indicator of what could become a global food crisis brought about by climate change. Utah developed collaborative work with a Chinese company to look at soil reclamation in hothouses located in Pudong China. Excessive nitrate applications coupled with clayey soils have resulted in saline conditions and poor drainage for growers. Collaboration is ongoing with Arizona to advance sensor and instrumentation for sensing of soil-fluid properties. Internal (USU) collaborations with an ecophysiologist are looking into issues related to geophysics for assessing soil properties in native ecosystems. Washington quantified capillary forces between different particles (sphere, cylinder, cube, disk, sheet, natural mineral particles) and a moving air-water interface. We also have studied the effects of remediation of seawater-affected aquifer with freshwater injection. The results indicate that the permeability was reduced by up to 70% when seawater was displaced with freshwater. We improved the WEPP (v2004.7) watershed model, so that it can be applied to adequately simulate forest watershed hydrology and erosion. Continued efforts are needed to further improve the ability of WEPP to properly account for soil freeze-thaw and thus transient soil hydraulic properties and hydrologic and erosion processes. Wyoming participated in ongoing field data collection for the following multi-investigator projects at the University of Wyoming: (1) nutrient dynamics in dryland wheat fields in southeastern Wyoming; (2) crop-range-livestock farm research in southeastern Wyoming; and (3) runoff generation due to snowmelt in the Snowy Range Mountains in southeastern Wyoming.<br /> <br /> Milestones <br /> Alaska is developing relationships between environmental factors and vapor intrusion, expanding field monitoring of Arctic gravel pads, and furthering the investigation of herbicide attenuation in subarctic environments using glyphosate. Arizona laid the foundation for two new multiyear research projects in collaboration with Scott Jones (USU): (1) Novel Gradient-Based and Surface Chamber Techniques for Monitoring Regulated and Greenhouse Gas Emissions from Animal Feeding Operations; and (2) A Novel Approach to Quantifying Soil Evaporation Rates with High Resolution Thermal Imaging and Heat Flux Measurements. We advanced image segmentation methods and demonstrated applicability of ERI and EMI techniques to harsh engineered environments (i.e. mine tailings). Schaap defined a methodology for Bayesian modification of pedotransfer functions releasing a new version of Rosetta PTFs. Developed community model for Lattice Boltzmann simulation of multiphase fluid dynamics. Kentucky 2010: Project 1: Complete chemical analyses on tracer samples; complete frequency-domain analysis on leaching depth, rainfall amount and intensity, and application time delay; apply field sampled hydraulic properties in numerical computer simulations of water flux and bromide transport. Complete M.S. Thesis. Project 2: Complete statistical analysis on scale-dependent association between optical indices measured in spring time and final yield in order to study the impact of measurement resolution for identifying appropriate management scales. Contribute to model developer for refining soil processes, and incorporation of a soil water, nitrogen and crop growth status update in the model; refine harvest index-related routines. Minnesota's approach and the outcome from the work to date provides results: generation of new information on mass and energy transport processes in soils at spatial and temporal scales appropriate for effective resource management, and improved understanding of the role of scale in basin-scale processes, including evapotranspiration, water balance and ecological functions and services. The results are in the form of atlases and tables of groundwater recharge associated with hydrologic units defined at various spatial scales. In this case the largest scale is the state level, but the methodology can be applied at the national level, the continental level, or even the global level. Oklahoma took initial steps toward the development of a real-time, freely available, drought monitoring system displaying plant available water across Oklahoma. This system will enable early detection and adaptive management to mitigate the negative impacts of drought on people, ecosystems and the economy. Oregon completed a series of laboratory saline evaporation tests within an environmentally controlled chamber. We have instrumented a new field site for quantifying the mass transport dynamics through a drying season. Texas (Bushland) developed and calibrated a new physically-based calibration model to estimate water contents using broadband dielectric techniques in fine-textured soils. Texas (A&M) sees great promise for the use of air-borne and space-borne remote sensing platforms for better understanding and characterization of the scale relationships in soil moisture and vadose zone hydraulic properties across the globe. In addition, we have developed several uncertainty estimation techniques for these important water and energy transport parameters in shallow porous media for better understanding of their spatial variability, physical controls, and scaling rules from local, footprint, watershed, to regional scales. Utah evaluated 10 different electromagnetic sensors as to their dielectric measurement capability and measurement frequency. Wyoming carried out a calibration of a combined soil water flow, heat transport, and CO2 production and a transport model for a rangeland soil in southeastern Wyoming. In addition, an application of a soil water flow and heat transport model to study the water and energy balance of dryland wheat fields in southeastern Wyoming occurred.<br />

Publications

Acharya, K. C. Schulman, M.H. Young. 2009. Physiological response of Daphnia magna to Linear Anionic Polyacrylamide: Ecological Implications for Receiving Waters. Archives of Environ. Contam. and Tox. Accepted.<br /> Al-Mulla, Y., J. Q. Wu, P. Singh, M. Flury, W. F. Schillinger, D. R. Huggins, and C. O. Stockle. 2009. Soil water and temperature in chemical versus reduced-tillage fallow in a Mediterranean climate. Appl. Eng. Agric. 25:4554.<br /> Andersen, D.S., R.T. Burns, L.B. Moody, M.J. Helmers, and R. Horton. 2009. Comparison of the Iowa State University  effluent limitation guidelines model with the soil-plant-air-water model for evaluating containment basin performance. Transactions ASAE. (in press).<br /> Bakker, M. and J.L. Nieber, 2009. Damping of Sinusoidal Surface Flux Fluctuations with Soil Depth, Vadose Zone Journal, 8: 119-126.<br /> Baumhardt, R.L., R.C. Schwartz, L.W. Greene, and J. Macdonald. 2009. Cattle gain and crop yield for a dryland wheat-sorghum-fallow rotation. Agron. J. 101:150-158.<br /> Benning, J.L. and D.L. Barnes. 2009. Comparison of Methods for the Determination of Diffusion Coefficients and Effective Porosities in Through-Diffusion Tests. Water Resources Research. 45, W09419, doi:10.1029/2008WR007236.<br /> Bittelli, M., and M. Flury. 2009. Errors in water retention curves determined with pressure plates and their effect on soil hydraulic functions. Soil Sci. Soc. Am. J. 73:14531460.<br /> Botros, F.E. T. Harter, Y. S. Onsoy, A. Tuli, and J.W. Hopmans. 2009. Spatial Variability of Hydraulic Properties and Sediment Characteristics in a Deep Alluvial Unsaturated Zone. Vadose Zone Journal. doi: 10.2136/vzj2008.0087<br /> Bradford, S. A., and E. Segal. 2009 Fate of indicator microorganisms under nutrient management plan conditions. Journal of Environmental Quality, 38:1728-1738.<br /> Bradford, S. A., H. N. Kim, B. Z. Haznedaroglu, S. Torkzaban, and S. L. Walker. 2009. Coupled factors influencing concentration dependent colloid transport and retention in saturated porous media, Environmental Science & Technology, 43, 6996-7002.<br /> Bradford, S. A., S. Torkzaban, F. Leij, J. Simunek, and M. Th. van Genuchten. 2009. Modeling the coupled effects of pore space geometry and velocity on colloid transport and retention. Water Resources Research, 45, W02414, doi:10.1029/2008WR007096.<br /> Caldwell, T.G., D.W. Johnson, W.W. Miller, R.G. Qualls, and R.R. Blank. 2009. Prescription fire and anion retention in Tahoe forest soils. Soil Science 174:594-600.<br /> Caldwell, T.G., E.V. McDonald, and M.H. Young. 2009. The seedbed microclimate and the active revegetation of disturbed lands in the Mojave Desert. Journal of Arid Environments 73:563-573.<br /> Chen, J., J. Zhu, M. H. Young, and R. B. Susfalk. 2009. An Integrated Approach for Modeling Solute Transport in Streams and Canals with Applications. Journal of Hydrology 378:128136, doi:10.1016/j.jhydrol.2009.09.012.<br /> Chen, W., L. Wu, A. Chang, Z. Hou. 2009. Assessing the effect of long-term crop cultivation on distribution of Cd in the root zone. Ecological Modeling. 220:18361843.<br /> Daanen, R.P. and J.L. NIEBER, 2009. Model for coupled liquid water flow and heat transport with phase change in a snowpack, J. Cold Regions Engineering, 23 (2): 43-68.<br /> Davis, D.D., R. Horton, J.L. Heitman, and T. Ren. 2009. Wettability and hysteresis effects on water sorption in relatively dry soil. Soil Sci. Soc. Am. J. 73:19471951.<br /> Deng H., M. Ye, M. G. Schaap, R. Khaleel (2009), Quantification of uncertainty in pedotransfer function-based parameter estimation for unsaturated flow modeling, Water Resour. Res., 45, W04409, doi:10.1029/2008WR007477.<br /> Derby, N.E., F.X.M. Casey, and R.E. Knighton. 2009. Long-Term Observations of Vadose Zone and Groundwater NO3-N Concentrations under Irrigated Agriculture. Vadose Zone J. 8:290-300, DOI: 10.2136/vzj2007.0162<br /> Dostert, P., Y. Efendiev, and B.P. Mohanty. Efficient uncertainty Quantification Techniques in Inverse Problems for Richards Equation Using Coarse-Scale Simulation Models. Advances of Water Resources. 32, 329339, 2009.<br /> Dun, S., J.Q. Wu, W.J. Elliot, P.R. Robichaud, D.C. Flanagan, J.R. Frankenberger, R.E. Brown, and A.C. Xu. 2009. Adapting the Water Erosion Prediction Project (WEPP) model for forest applications, J. Hydrol. 466, 4654.<br /> Estevez, R. and S.B. Jones. 2009. Frequency Domain Soil Moisture Determination Using an Open-Ended Dielectric Probe. ASABE Paper No. 097130. St. Joseph, Mich.: ASABE.<br /> Evett, S.R. and R.C. Schwartz. 2009. Comments on J. Vera et al., Soil water balance trial involving capacitance and neutron probe measurements [Agric. Water Manage. 96 (2009) 905911]. Agric. Water Mgmt. 97:182-184.<br /> Evett, S.R., R.C. Schwartz, J.A. Tolk and T.A. Howell. 2009. Soil profile water content Determination: Spatiotemporal Variability of Electromagnetic and Neutron Probe Sensors in Access Tubes. Vadose Zone J. 8:926-941.<br /> Fan, J., M. Shao, Q. Wang, S. Li and S.B. Jones. 2009. Landscape Changes and Vegetation Restoration in the Wind-Water Crisscross Region of the Loess Plateau, China. ASABE Paper No. 097022. St. Joseph, Mich.: ASABE.<br /> Flury, M. 2009. Water conservation using wheat straw residues. CSA News 54(2):4.<br /> Flury, M., J. B. Mathison, J. Q. Wu, W. F. Schillinger, and C. O. Stockle. 2009. Water vapor diffusion through wheat straw residues. Soil Sci. Soc. Am. J. 73:3745.<br /> Fu, X., M. Shao, X. Wei, and R. Horton. 2009. Soil organic carbon and total nitrogen as affected by vegetation types in Northern Loess Plateau of China. Geoderma (in press).<br /> Fu, X., M. Shao, X. Wei, and R. Horton. 2009. Effects of two perennials, fallow and millet on distribution of phosphorous in soil and biomass on sloping loess land, China. Catena 77:200206.<br /> Fu, X., M. Shao, X. Wei, and R. Horton. 2009. Urea-derived nitrogen losses in a semiarid region of China Loess Plateau. SAGB: Acta Agriculturae Scandinavica, Section B - Plant Soil Science (in press).<br /> Han, X., M. Shao, A. Tsunekawa, and R. Horton. 2009. Estimating van Genuchten model parameters of undisturbed soils using an integral method. Pedosphere (in press).<br /> Hanson, B.R., D.E. May, J. Simunek, J.W. Hopmans, and R.B. Hutmacher.2009. Drip irrigation provides for profitable irrigation of tomatoes in the San Joaquin Valley. California Agriculture paper. 63(3):131-136.<br /> Haznedaroglu, B. Z., H. N. Kim, S. A. Bradford, and S. L. Walker. 2009. Relative transport behavior of Escherichia coli O157:H7 and Salmonella enterica serovar Pullorum in packed bed column systems: Influence of solution chemistry and cell concentration. Environmental Science & Technology, 43, 1838-1844.<br /> Heinse, R., S.B. Jones, M. Tuller, G.E. Bingham, I. Podolskiy, and D. Or, 2009. Providing Optimal Root-Zone Fluid Fluxes: Effects of Hysteresis on Capillary-Dominated Water Distributions in Reduced Gravity. Proceedings of the 39th International Conference on Environmental Systems (ICES), July 2009, Savannah, GA. SAE Technical Paper 2009-01-2360.<br /> Hou, Z., W. Chen, X. Li, L. Xiu, L. Wu. 2009. Effects of salinity and fertigation practice on cotton yield and 15N recovery. J. Ag. Water Manage. 96:1483-1489.<br /> Hu, W., M. Shao, Q. Wang, J. Fan, and R. Horton. 2009. Temporal changes of soil hydraulic properties under different land uses. Geoderma 149:355-366.<br /> Iassonov, P., T. Gebrenegus, and M. Tuller, 2009. Segmentation of X-Ray CT Images of Porous Materials: A Crucial Step for Characterization and Quantitative Analysis of Pore Structures. Water Resour. Res., 45, W09415, doi:10.1029/2009WR008087.<br /> Ines, A.V.M. and B.P. Mohanty. Near-Surface Soil Moisture Assimilation to Quantify Effective Soil Hydraulic Properties Using Genetic Algorithm. 2. with Air-Borne Remote Sensing During SGP97 and SMEX02. Water Resources Research. 44, 10.1029/2007WR007022, 2009.<br /> Jiménez-Martínez, J., T.H. Skaggs, M.Th. van Genuchten, and L. Candela. 2009. A root zone modelling approach to estimating groundwater recharge from irrigated areas. J. Hydrol. 367:138149.<br /> Jones, S.B., R.M. Estevez and D.A. Robinson. 2009. Novel mobile soil water content sensing techniques. ASABE Paper No. 097158. St. Joseph, Mich.: ASABE.<br /> Jones, S.B., R. Heinse, B. Bugbee, D. Or and G.E. Bingham. 2009. Porous plant growth media design considerations for Lunar and Martian habitats. SAE Technical Paper no. 2009-01-2361.<br /> Kamai, T. N. Weisbrod, and M.I. Dragila. 2009. Impact of ambient temperature on evaporation from surface-exposed fractures. Water Resources Research. 45. W02417. soi:10.1029/2008WR007354.<br /> Kamai, T., A. Tuli, G. J. Kluitenberg, and J. W. Hopmans. 2008. Soil water flux density measurements near 1 cm d1 using an improved heat pulse probe design. Water Resour. Res., 44, W00D14, doi:10.1029/2008WR006956. <br /> Kamai, T., G.J. Kluitenberg, and J.W. Hopmans. 2009. Design and numerical analysis of a button heat pulse probe for soil water content measurements. Vadose Zone Journal. 8:1-7. Doi:10.2136/vzj2008.0106.<br /> Kavouras, I.G., V. Etyemezian, G. Nikolich, M.H. Young, J. Gillies, D.S. Shafer. 2009. A New technique for characterizing the efficacy of fugitive dust suppressants. J. Air Waste Mgmt. Assoc. 59:603-612.<br /> Kelleners, T.J., E.S. Ferre-Pikal, M.G. Schaap, G.B. Paige, 2009, Calibration of Hydra Impedance Probes Using Electric Circuit Theory. Soil Soc. Am. J., 73(2):453-465.<br /> Kelleners, T.J., D.G. Chandler, J.P. McNamara, M.M. Gribb, and M.S. Seyfried. 2009. Modeling the water and energy balance of vegetated areas subject to snow accumulation. Vadose Zone J. 8:1013-1030.<br /> Kelleners, T.J., E.S. Ferre-Pikal, M.G. Schaap, and G.B. Paige. 2009. Calibration of Hydra impedance probes using electric circuit theory. Soil Sci. Soc. Am. J. 73:453-465.<br /> Kelleners, T.J., G.B. Paige, and S.T. Gray. 2009. Measurement of the dielectric properties of Wyoming soils using electromagnetic sensors. Soil Sci. Soc. Am. J. 73:1626-1637.<br /> Kim, H. N., S. A. Bradford, and S. L. Walker. 2009. Escherichia coli O157:H7 transport in saturated porous media: Role of solution chemistry and surface macromolecules. Environmental Science & Technology, 43 (12), 4340-4347 <br /> Kim, H. N., S. L. Walker, and S. A. Bradford. 2009. Coupled factors influencing the transport and retention of Cryptosporidium Parvum oocysts in saturated porous media. Water Research, In Press. <br /> Kim, H. N., S. L. Walker, and S. A. Bradford. 2009. Macromolecule mediated transport and retention of Escherichia coli O157:H7 in saturated porous media. Water Research, In Press.<br /> Kim, H. N., Y. Hong, I. Lee, S. A. Bradford, and S. L. Walker. 2009. Surface characteristics and adhesion behavior of Escherichia coli O157:H7: Role of extracellular macromolecules. Biomacromolecules, 10, 2556-2564. <br /> King, A.P., K. J. Evatt, J. Six, R.M. Poch, D.E. Rolston, and J.W. Hopmans. 2009. Annual carbon and nitrogen loadings for a furrow-irrigated field. Agric. Water Management. Doi:10.1016/j.agwat.2009.01.001.<br /> Labahn, S.K. J.C. Fisher, M.H. Young., E. Robleto, D.P. Moser. 2009. Microbially-mediated aerobic and anaerobic degradation of acrylamide in a western U.S. irrigation canal. J. Env. Qual. Accepted.<br /> Lee, J. E.A. Laca, Ch van Kessel, D.E. Rolston, J. W. Hopmans and J. Six. 2009. Tillage effects on spatiotemporal variability of particulate organic matter. Applied and Environmental Soil Science, doi:10.1155/2009/219379. <br /> Lee, J., J. W. Hopmans, D.E. Rolston, S.G. Baer, and J. Six. 2009. Determining soil carbon stock changes: Simple bulk density corrections fail. Agricultural and Ecological Ecosystems: 134:251-256. Doi:10.1016/j.agee.2009.07.006.<br /> Leek, R., J.Q. Wu, L. Wang, T.P. Hanrahan, M.E. Barber, and H. Qiu. 2009. Heterogeneous characteristics of streambed saturated hydraulic conductivity of the Touchet River, southeastern Washington, USA, Hydrol. Process. 23, 12361246.<br /> Leij, F. J., and S. A. Bradford. 2009. Combined physical and chemical non-equilibrium transport model: Analytical solution, moments, and application to colloids. Journal of Contaminant Hydrology, 110, 87-99.<br /> Li , Y., R. Horton, T. Ren and C. Chen. 2009. Investigating time scale effects on reference evapotranspiration from Epan data in north China. Journal of Applied Meteorology and Climatology, doi: 10.1175/2009JAMC2130.1.<br /> Li , Y., R. Horton, T. Ren and C. Chen. 2010. Prediction of annual reference evapotranspiration using climatic data. Agricultural Water Management (in press).<br /> Li, H., L. Wu, H. Zhu, and J. Hou. 2009. Ion Diffusion in the Time-Dependent Potential of the Dynamic Electric Double Layer. J. Phys. Chem. C. 113:13241-13248.<br /> Liu, J., X. Chen, J. Zhang, and M. Flury. 2009. Coupling the Xinanjiang model to a kinematic flow model based on digital drainage networks for flood forecasting. Hydrol. Processes 23:13371348.<br /> Lü, H., Y. Zhu, T.H. Skaggs, Z. Yu. 2009. Comparison of measured and simulated water storage in dryland terraces of the Loess Plateau, China. Agric. Water Manage., 96:299306.<br /> Lu, J., L. Wu and B. Faber. 2009. Erosion control and runoff management. In J. Newman (ed.) Greenhouse and Nursery Management Practices to Protect Water Quality (Division of Agricultural and Natural Resources Publication, in press).<br /> Lu, S., Z. Ju, T. Ren, and R. Horton. 2009. A general approach to estimate soil water content from thermal inertia. Agric. Forest Meteorol., doi:10.1016/j.agrformet.2009.05.011.<br /> Magri, A., D. A. Haith, A. M. Petrovic, L. Wu, and R. L. Green. 2009. Development and testing of a comprehensive model of pesticide losses from turf. In: M. Nett, A. M. Petrovic, M. J. Carroll, and B. H. Horigan (eds.) The Role of Turfgrass Management in the Water Quality of Urban Environments. Am. Chem. Soc.,Oxford Press (in press).<br /> Mangiafico, S., J. Newman, D.J. Merhaut, J. Gan, B. Faber, and L. Wu. 2009. Survey of nutrients and pesticides in runoff from production nurseries and citrus and avocado orchards. HortTechnology. 19: 360  367.<br /> MattheesDose, H.L. 2009. Soil Properties Affecting Oil Well Access Road Reclamation. M.S. thesis North Dakota State Univ., Fargo.<br /> Mohanty, B.P. and N.N. Das. A New Multiscale Data Assimilation Algorithm to Downscale Satellite-Based Surface Soil Moisture Data, Procs. of 8th International Association of Hydrologic Sciences Assembly (IAHS), September 6-12, 2009, Hyderabad, India, CD-Rom, 2009.<br /> Mohanty, B.P., N.N. Das, R.B. Jana, and A.V.M. Ines. Effective Soil Hydraulic Parameter Estimation at Different Spatial Scales, Procs. of Water, Environment, Energy, and Society (WEES), January 12-17, New Delhi, India, pp. 188-196, 2009.<br /> Nasta P., T. Kamai, G.B. Chirico, J. W. Hopmans and N. Romano. 2009. Scaling soil water retention functions using particle-size distribution. J. Hydrology 374:223-234. doi:10.1016/j.hydrol.2009.06.007<br /> Oduor, P.G., X.T. Santos, and F.X.M. Casey. 2009. Solute Exclusionary Properties of Porous Shale Wafers. J. Porous Media. 12(6): 501-518.<br /> Oduor, P.G., X.T. Santos, K. Forward, N. Sharp, C. Bue, F.X.M. Casey, and J. Abwawo. 2009. Semi-Empirically Derived Petrophysical and Thermodynamical Coefficients of Permselective Shales -Implications on Ore Mineralization. Membrane Sci. (In press).<br /> Or, D., M. Tuller, and S.B. Jones, 2009. Liquid Behavior in Partially-Saturated Porous Media under Variable Gravity. Soil Sci Soc Am J, 73:341350, doi:10.2136/sssaj2008.0046.<br /> Pan, F., M. Ye, J. Zhu, Y.-S. Wu, B. X. Hu, and Y. Yu. 2009. Effect of Water Retention Parameters on Predictive Uncertainty of Unsaturated Flow and Contaminant Transport. Vadose Zone Journal 8: 158-166, doi:10.2136/vzj2008.0092.<br /> Pan, F., M. Ye, J. Zhu, Y.-S. Wu, B. X. Hu, and Z. Yu. 2009. Incorporating Layer- and Local-Scale Heterogeneities in Numerical Simulation of Unsaturated Flow and Tracer Transport. Journal of Contaminant Hydrology 103:194-205, doi:10.1016/j.jconhyd.2008.10.012.<br /> Pérez Guerrero, J.S., L.C.G. Pimentel, T.H. Skaggs, and M.Th. van Genuchten. 2009. Analytical solution of the advection-diffusion transport equation using a change-of-variable and integral transform technique. Int. J. Heat Mass Transf. 52:32973304 <br /> Pérez Guerrero, J.S., T.H. Skaggs, and M.Th. van Genuchten. 2009. Analytical Solution for Multi-Species Contaminant Transport Subject to Sequential First-Order Decay Reactions in Finite Media. Transp. Porous Media, 80:373387. <br /> Porter, M.L., M.G. Schaap, and D. Wildenschild, 2009, Lattice-Boltzmann Simulations of the Capillary Pressure -Saturation - Interfacial Area Relationship in Porous Media, Accepted by Advances in Water Resources., 32(11):1632-1640.<br /> Qazi, A.M., M. Akram, N. Ahmad, J. Artiola, and M. Tuller, 2009. Economical and Environmental Implications of Solid Waste Compost Applications to Agricultural Fields in Punjab, Pakistan. Waste Management, Waste Management, 29(9):2437-2445, doi:10.1016/j.wasman.2009.05.006.<br /> Or, D., M. Tuller and S.B. Jones. 2009. Liquid Behavior in Partially-Saturated Porous Media under Variable Gravity. Soil Sci. Soc. Am. J. 73:341-350, doi:10.2136/sssaj2008.0046. <br /> Ranft, R.D., S.S. Seefeldt, M. Zhang, and D.L. Barnes. Accepted. Development of a Soil Bioassay for Triclopyr Residues and Comparison with a Laboratory Extraction. Weed Technology.<br /> Robinson, D.A., I. Lebron, R.J. Ryel and S.B. Jones. 2009. Soil Water Repellency, a Method of Soil Moisture Sequestration in Pinyon  Juniper Woodland. Soil Sci. Soc. Am. J. 74(2).<br /> Robinson, D.A., S.B. Jones, J.M.Jr. Blonquist, R. Heinse, I. Lebron, and T.E. Doyle. 2009. The Dielectric Response of the Tropical Hawaiian Mars Soil Simulant JSC Mars-1. Soil Sci. Soc. Am. J. 73 (4):1113-1118.<br /> Sawatzky, D.A. 2009. Hydraulic Efficiency in Biofilm Affected Tile Drains. M.S. thesis North Dakota State Univ., Fargo.<br /> Schwartz, R.C., Evett, S.R. and Bell, J.M.. Complex permittivity model for time domain reflectometry soil water content sensing. II. Calibration. Soil Sci. Soc. Am. J. 73:898-909.<br /> Schwartz, R.C., Evett, S.R., Pelletier, M.G., and Bell, JM. Complex permittivity model for time domain reflectometry soil water content sensing. I. Theory. Soil Sci. Soc. Am. J. 73:886-897.<br /> Segal, E., P. Shouse, and S. A. Bradford. 2009. Deterministic analysis and upscaling of bromide transport in a heterogeneous vadose zone. Vadose Zone Journal, 8:601-610.<br /> Segal, E., P.J. Shouse, S.A. Bradford, T.H. Skaggs, and D.L. Corwin. 2009. Measuring Particle Size Distribution Using Laser Diffraction: Implications for Predicting Soil Hydraulic Properties. Soil Sci., 174:639645.<br /> Shang, J., M. Flury, and Y. Deng. 2009. Force measurements between particles and the air- water interface: Implications for particle mobilization in unsaturated porous media. Water Resour. Res. 45:W06420, doi:10.1029/2008WR007384.<br /> Shaw, B.D., A. Tuli, J-B. Wei, and J.W. Hopmans. 2009. Analytical modeling of soil solution monitoring by diffusion in porous cups. Transport in Porous Media. DOI 10.1007/s11242-009-9404-3<br /> Simunek, J., and J.W. Hopmans. 2009. Modeling compensated root water and nutrient uptake. Ecological Modeling. 120:505- 521. doi:10.1016/j.ecolmodel.2008.11.004 <br /> Singh, P., J.Q. Wu, D.K. McCool, S. Dun, C-H Lin, and J.R. Morse. 2009. Winter hydrological and erosion processes in the US Palouse region: Field experimentation and WEPP simulation, Vadose Zone J. 8, 426436.<br /> Siripattanakul, S., W. Wirojanagud, J.M. McEvoy, F.X.M. Casey, and E. Khan. 2009. A Feasibility Study of Immobilized and Free Mixed Culture Bioaugmentation for Treating Atrazine in Infiltrate. J. Hazard. Mater., doi:10.1016/j.jhazmat.2009.03.025.<br /> Siripattanakul, S., W. Wirojanagud, J.M. McEvoy, F.X.M. Casey, and E. Khan. 2009. Atrazine Removal in Agricultural In
ltrate by Bioaugmented Polyvinyl Alcohol Immobilized and Free Agrobacterium radiobacter J14a: A Sand Column Study. Chemosphere.74:308313. Epub 2008 Oct 10.<br /> Siyal, A.A., and T.H. Skaggs. 2009. Measured and simulated soil wetting patterns under porous clay pipe sub-surface irrigation. Agric. Water Manage., 96:893904. <br /> Siyal, A.A., M.Th. van Genuchten, and T.H. Skaggs. 2009. Performance of Pitcher Irrigation System. Soil Sci. 174:312320.<br /> Thompson, M.L., F.X.M. Casey, H. Hakk, and G.L. Larsen, T.M. DeSutter. 2009. Occurrence and Pathways of Manure-Borne 17²-Estradiol in Vadose Zone Water. Chemosphere doi:10.1016/j.chemosphere.2009.03.037.<br /> Torkzaban, S., H. N. Kim, J. Simunek, and S. A. Bradford. 2009. Hysteresis of colloid retention and release in saturated porous media during transients in solution chemistry. Environmental Science & Technology, In Press.<br /> Torkzaban, S., S. L. Walker, and S. A. Bradford. 2009. Reply to comment by William P. Johnson et al. on Transport and fate of bacteria in porous media: Coupled effects of chemical conditions and pore space geometry, Water Resources Research, 45, W09604, doi:10.1029/2008WR007576. <br /> Toth, T., M.G. Schaap., and Z. Molnar, 2008, Utilization of soil-plant interrelations through the use of multiple regression and artificial neural network in order to predict soil properties in Hungarian solonetzic grasslands. Cereal Research Communications, 36:1447-1450 (Part 3, Suppl. S). <br /> Tuli, A., J.-B. Wei, B. D. Shaw, and J.W. Hopmans. 2009. In situ monitoring of soil solution nitrate: Proof of concept. Soil Science Society Journal. 73(2). Doi: 10.2136/sssaj2008.0160 .<br /> Twarakavi,N.K.C., J. `imonek and M. G. Schaap, 2009,. Development of Pedotransfer Functions for Estimation of Soil Hydraulic Parameters Using Support Vector Machine, Soil Science Society of Am. J., 73(5):1443-1452.<br /> Vereecken, H., T. Kamai, T. Harter, R. Kasteel, J. W. Hopmans, J. A. Huisman, and J. Vanderborght. 2008. Comment on Field observations of soil moisture variability across scales by James S. Famiglietti et al., Water Resour. Res., 44, W12601, doi:10.1029/2008WR006911.<br /> Viola, R., F. Zama, M. Tuller, E. Mesini, 2009. Simulation of Incompressible Flow through Rhombohedric Pores. Proceedings of the 2009 European COMSOL Conference, Milan, Italy, October 14-16.<br /> Wang, C., R. Estevez, C.M.P. Vaz and S.B. Jones. 2009. Quantifying the Impact of Soil Properties on the Performance of Electromagnetic Water Content Sensors. ASABE Paper No. 096999. St. Joseph, Mich.: ASABE.<br /> Wang T., V. A. Zlotnik, J. `imunek, M. G. Schaap (2009), Using pedotransfer functions in vadose zone models for estimating groundwater recharge in semiarid regions, Water Resour. Res., 45, W04412, doi:10.1029/2008WR006903.<br /> Wang, L., R. Horton, and Z. Gao. 2009. Comparison of six algorithms to determine the soil apparent thermal diffusivity at a site in the Loess Plateau of China. Soil Sci. (in press).<br /> Wang, Q., R. Horton, and J. Fan. 2009. An analytical solution for one-dimensional water infiltration and redistribution in unsaturated soil. Pedosphere 19:104110.<br /> Wei, X., M. Shao, R. Horton, and X. Han. 2009. Humic acid transport in water-saturated porous media. Environ. Model. Assess. DOI 10.1007/s10666-008-9186-y.<br /> Wei, X., M. Shao, X. Fu, and R. Horton. 2009. Changes in soil organic carbon and total nitrogen after 28 years grassland afforestation: Effects of tree species, slope position and soil order. Plant and Soil (in press).<br /> Wei, X., M. Shao, X. Fu, R. Horton, Y. Li, and X. Zhang. 2009. Distribution of soil organic C, N and P in three adjacent land use patterns in the northern Loess Plateau, China. Biogeochemistry DOI 10.1007/s10533-009-9350-8.<br /> Weisbrod, N., M.I. Dragila, U. Nachshon, and M. Pilldersdorf. 2009. Falling through the cracks: The role of fractures in Earth-atmosphere gas exchange. Geoph. Res. Let. 36:L02401, doi:10,1029/2008GL036096.<br /> Wendroth, O., S. Koszinski, V. Vasquez. 2010. Soil Spatial Variability. In [Editor] Handbook of Soil Science (accepted).<br /> Wu, L., W. Chen, C. French and A. Chan. 2009. Technical bulletin for the safe application of reclaimed water reuse in the southwestern United States (UC Division of Agricultural and Natural Resources peer-reviewed Publication) (http://ucanr.org/freepubs/finalpage.cfm?s=8357&cat=11&subcat=14).<br /> Xu, J., L. Wu, W. Chen, P. Jiang, A. C. Chang. 2009. Pharmaceuticals and personal care products (PPCPs), and endocrine disrupting compounds (EDCs) in runoff from a potato field irrigated with treated wastewater in southern California. Journal of Health Science. 55:306-310.<br /> Yang, C. and S.B. Jones. 2009. INV-WATFLX, a code for simultaneous estimation of soil properties and planer vector water flux from penta-needle heat-pulse probes. Computers & Geosciences. doi:10.1016/j.cageo.2009.04.005<br /> Young, M. H., E. A. Moran, Z. Yu, J. Zhu and D. M. Smith. 2009. Reducing Saturated Hydraulic Conductivity of Soil with Polyacrylamide. Soil Science Society of America Journal 73:13-20, doi:10.2136/sssaj2007.0378.<br /> Young, M.H., T.G. Caldwell, D.G. Meadows, and L.F. Fenstermaker. 2009. Variability of soil physical and hydraulic properties at the Mojave Global Change Facility, Nevada: Implications for water budget and evapotranspiration. Journal of Arid Environments 73:733-744.<br /> Zhang, J., Z. Li, G. Ge, W., Sun, Y. Liang, and L. Wu. 2009. Impacts of soil organic matter, pH and exogenous copper on sorption behavior of norfloxacin in three soils. J. Environ. Sci. 21:1-9.<br /> Zhang, J.X., J.Q. Wu, W.J. Elliot, S. Dun, and K-T Chang. 2009. Effects of DEM resolution on WEPP hydrologic and erosion prediction: a case study of two forest watersheds in northern Idaho, Trans. ASABE 52, 447457.<br /> Zhou, J., X. Zheng, M. Flury, and G. Lin. 2009. Permeability changes during remediation of an aquifer affected by sea-water intrusion: a laboratory column study. J. Hydrol. (Amsterdam) 376:557566.<br /> Zhu, J., and D. Sun. 2009. Effective Soil Hydraulic Parameters for Transient Flows in Heterogeneous Soils. Vadose Zone Journal 8:301-309, doi:10.2136/vzj2008.0004.<br /> Zhu, J., and M. H. Young. 2009. Sensitivity and Uncertainty of Ground-Water Discharge Estimates for Semi-Arid Shrublands. Journal of the American Water Resources Association (JAWRA) 45(3):641-653, doi:10.1111/j.1752-1688.2009.00312.x.<br /> Zhu, J., and M. H. Young. 2009. Sensitivity of Unlined Canal Seepage to Hydraulic Properties of Polyacrylamide (PAM) Treated Soil. Soil Science Society of America Journal 73:695-703, doi:10.2136/sssaj2008.0261.<br /> Zhu, J., K. F. Pohlmann, J. B. Chapman, C. E. Russell, R. W. H. Carroll, and D. S. Shafer. 2009. Sensitivity of Solute Advective Travel Time to Porosities of Hydrogeologic Units. Ground Water, in press.<br /> Zhu, Y., L. Ren, T.H. Skaggs, H. Lü, Z. Yu, Y. Wu, and X. Fang. 2009. Simulation of Populus euphratica root uptake of groundwater in an arid woodland of the Ejina Basin, China. Hydrol. Process. 23: 24602469.<br /> <br /> Book Chapters<br /> Casey, F.X.M. and Shore, L.S. 2009. Physiochemical characterization of steroid hormones in soil columns. 2009. In Laurence Shore and Amy Pruden, eds. Hormones and Pharmaceuticals Generated by Concentrated Animal Feeding Operations and their Transport in Water and Soil. Pg. 29-36. ISBN: 978-0-387-92833-3.<br /> Hunt AG and RP Ewing (2009). Percolation theory for flow in porous media. Lecture notes in physics 771, Springer, Berlin.<br /> Shore, L.S., and F.X.M. Casey. 2009. Transport of steroid hormones in soil and groundwater. 2009. In Laurence Shore and Amy Pruden, eds. Hormones and Pharmaceuticals Generated by Concentrated Animal Feeding Operations and their Transport in Water and Soil. Pg. 3746. ISBN: 978-0-387-92833-3. <br /> <br /> Abstracts <br /> Acharya, K., Y. Li, M. Stone, Z. Yu, M. Young, D. Shafer, J. Zhu and J. Warwick, Spatiotemporal Distribution of Algal and Nutrient, and Their Correlations Based on Long-term Monitoring Data in Lake Taihu, China. AGU Fall Meeting, December 1418, 2009, San Francisco, CA.<br /> Aravena, J.E., S.W. Tyler, and M. Berli, Effect of aggregates compaction on soil hydraulic properties due to root growth. AGU Fall Meeting, December 1418, 2009, San Francisco, CA.<br /> Bacon, S.N., E.V. McDonald, T.G. Caldwell, and G.K. Dalldorf, Alluvial fan sedimentation in response to strengthening of late Holocene ENSO variability in the Sonoran Desert, southwest Arizona. Geological Society of America Annual Meeting, November 18-23, 2009, Portland, OR.<br /> Barnes, D.L. 2009. Fate and Transport of Petroleum Spills in Arctic Soil and Gravel Pads. Presented at the 2009 Alaska Forum on the Environment, Anchorage, Alaska, February 2-6.<br /> Berger, P.A., R. Heinse, H. Abdu, M. Tuller, and S.B. Jones, 2009. Geophysical Characterization of Inactive Mine Tailings  A First Step for Revegetation. SSSA International Annual Meeting, Pittsburgh, PA, November 1-5, 2009.<br /> Berger, P.A., R. Heinse, M. Tuller, S.B. Jones. Geophysical Characterization of Inactive Mine Tailings  A First Step for Revegetation. 2009. ASA-CSSA-SSSA Annual Meeting, Pittsburgh, PA - Nov. 1-5, See Agronomy Abstracts, ASA, Madison, WI.<br /> Berli, M., M. Menon, T. A. Ghezzehei, N. Pillai, E.E. Regentova, P.S. Nico, M.H. Young, and S.W. Tyler, A step toward unraveling rhizosphere physics, AGU Fall Meeting, December 1418, 2009, San Francisco, CA.<br /> Caldwell, T.G., E.V. McDonald, S.N. Bacon, M.H. Young, and R. Schumer, Paleoclimate simulations and solute nitrate accumulation in a hyper-arid desert soil, ASA-CSA-SSSA Annual Conference, November 2-6, 2009, Pittsburgh, PA.<br /> Carlisle, J, S.B. Jones, D.G. Tarboton, L. Hipps and J.L. Boettinger. 2009. Instrumentation Enhancement at the T.W. Daniel Experimental Forest: A Drought Management Initiative Project. Spring Runoff Conference, Eccles Conference Center, Utah State University, Logan, UT, April 2-3.<br /> Casey, F.X.M. 2009. Reproductive Hormones in the Environment. Coalition of National Science Foundation. Capitol Hill, Washington D.C. <br /> Casey, F.X.M., S. Shrestha, H. Hakk, D. Smith, G.L. Larsen, and G. Padmanabhan. 2009. The Fate and Transport of Reproductive Hormones in the Environment. In Fate and Transport of Microconstituents within the Subsurface Environment During Water Reuse Applications. American Geophysical Union, San Francisco, CA, December 14-18, 2009.<br /> Chen, L., L. Xiang, M.H. Young, Z. Yu., Parameter optimization for Green-Ampt infiltration model, AGU Fall Meeting, December 1418, 2009, San Francisco, CA.<br /> Chen-Lopez, J.C., M. Tuller, G.A. Giacomelli, and P. Waller, 2009. Optimization of Root Zone Fluid Fluxes in Greenhouse Substrates. SSSA International Annual Meeting, Pittsburgh, PA, November 1-5, 2009.<br /> Chief. K, T. Caldwell, and M.H. Young, Spatial variability of air and water permeability for two watersheds in the Mojave and Sonoran Deserts, ASA-CSA-SSSA Annual Conference, November 2-6, 2009, Pittsburgh, PA.<br /> Dalldorf, G.K., T. G. Caldwell, S.N. Bacon, M. H. Young, J. Miller and E.V. McDonald, Rapid characterization of runoff potential on arid alluvial fans using terrain prediction and geomorphic mapping, American Association of Geographers Annual Meeting, March 26, 2009, Las Vegas, NV.<br /> Derby, N.E., F.X.M. Casey, T.M. DeSutter, H. Hakk and W. Shelver. 2009. The Effects of Composting On Swine Manure Nutrients and Hormones. In Annual Meetings Abstracts [CD-ROM]. ASA, CSSA, and SSSA, Madison, WI. - Advisee<br /> DeSutter, T., D. Franzen, F.X.M. Casey, D. Hopkins, B. Saini-Eidukat and A. Akyuz. 2009. Distribution of Total Hg in North Dakota Soils. In Annual Meetings Abstracts [CD-ROM]. ASA, CSSA, and SSSA, Madison, WI.<br /> Devitt, D.A., L.K. Fenstermaker, M.H. Young, B. Conrad and B. Bird, Evapotranspiration of mixed shrub communities in phreatophytic zones of the Great Basin, AGU Fall Meeting, December 1418, 2009, San Francisco, CA. (Invited)<br /> Doyle, T.E., A.T. Tew, D.A. Robinson, and S.B. Jones. 2009. Modeling the Dielectric Response of Aggregated Soils. Spring Runoff Conference, Eccles Conference Center, Utah State University, Logan, UT, April 2-3.<br /> Dragila, M.I., and N. Weisbrod. 2009. Impact of atmospheric boundary layer temperature variations on moisture venting from fractures and cracks. American Geophysical Union Conference, San Francisco, December 2009. H51B-0770.<br /> Dragila, M.I.. 2009 Armored Water Droplets: How They Form and Their Role in Water Redistribution and Soil Erosion.<br /> Estevez, R.M. and S.B. Jones. 2009. Frequency Domain Soil Moisture Determination Using an Open-Ended Dielectric Probe. ASABE Annual Meeting, Reno Nevada, June 21-24.<br /> Fan J. and S.B. Jones. 2009. Limitations for Applying the Gradient-Based Soil CO2 Efflux Method. Spring Runoff Conference, Eccles Conference Center, Utah State University, Logan, UT, April 2-3.<br /> Fan, J., M. Shao, Q. Wang, S. Li and S.B. Jones. 2009. Landscape Changes and Vegetation Restoration in the Wind-Water Crisscross Region of the Loess Plateau, China. ASABE Annual Meeting, Reno Nevada, June 21-24.<br /> Fang, Z. ; M. G. Schaap and S. P. Neuman. 2009. Comparison of vadose zone flow simulations based on hydraulic parameters derived from lab data, pedotransfer functions, Bayesian updating and inverse modeling, AGU Fall Meeting, San Francisco, December 17, H43F-1084.<br /> Fenstermaker, L., and M.H. Young, Carbon flux and spectral response of biological soil crust to soil moisture status, ASA-CSA-SSSA Annual Conference, November 2-6, 2009, Pittsburgh, PA.<br /> Guy, A., T. DeSutter, F.X.M. Casey and J. Leitch. 2009. Major Flooding of the Red River of the North: Impacts On Water and Soil Qualities in An Urban Environment. In Annual Meetings Abstracts [CD-ROM]. ASA, CSSA, and SSSA, Madison, WI. - Student Advisee <br /> Heinse, R., Jones, S.B., H. Abdu and D.A. Robinson. Time-lapse Characterization of Soil Moisture Dynamics  A First Step towards Ecological Integrity. 2009. AGU Fall Meeting Abstracts, San Francisco, CA, December 14-18.<br /> Heinse, R., S.B. Jones, M. Tuller, G. Bingham, I. Podolskiy, and D. Or, 2009. Providing Optimal Root-Zone Fluid Fluxes: Effects of Hysteresis on Capillary-Dominated Water Distributions in Microgravity. 39th International Conference on Environmental Systems (ICES), Savannah, Georgia, USA, July 12-16, 2009<br /> Heinse, R., S.B. Jones, M. Tuller, G.E. Bingham, I. Podolskiy and D. Or (2009). Providing Optimal Root Zone Fluxes: Challenges of Capillary-Driven Hysteretic Water Distributions in Microgravity. 39th International Conference on Environmental Systems (ICES), Hyatt Regency, Savannah, Georgia, USA, July 12 - 16.<br /> Jana, R., and B.P. Mohanty, Physical Controls of Soil Hydraulic Parameter Scaling. AGU Fall Meeting Abstract. 2009.<br /> Jones, S.B., C. Wang, D.A. Robinson and M. Tuller. Exploring Soil Properties through Electromagnetic Sensor-based Complex Dielectric Permittivity. 2009. AGU Fall Meeting Abstracts, San Francisco, CA, December 14-18.<br /> Jones, S.B., C. Wang, D.A. Robinson, and M. Tuller, 2009. Exploring Soil Properties through Electromagnetic Sensor-Based Complex Dielectric Permittivity. Eos Trans. AGU, 90(52), Fall Meet. Suppl., Abstract H33A-0847.<br /> Jones, S.B., C. Yang, and M. Tuller, 2009. Soil Infiltration and Evaporation Determination using Heat-Pulse Measurements and Energy Balance Modeling. Spring Runoff Conference, Logan, UT, April 2-3, 2009.<br /> Jones, S.B., H. Abdu, R. Heinse, D.A. Robinson and R.J. Ryel. 2009. Identifying Soil Resource Pools within Forest Communities using Eco-Geophysics. ASA-CSSA-SSSA Annual Meeting, Pittsburgh, PA - Nov. 1-5, See Agronomy Abstracts, ASA, Madison, WI.<br /> Jones, S.B., I. Podolskiy, R. Heinse, S.T. Topham, V.N. Sytchev, D. Or and G.E. Bingham. 2009. Porous Media Fluid Transport in Microgravity: The ORZS Flight Experiments. Presented at the 17th International Academy of Astronautics Humans in Space Symposium, Moscow, Russia, June 7-11.<br /> Jones, S.B., R. Heinse, B. Bugbee, D. Or and G.E. Bingham. Porous plant growth media design considerations for Lunar and Martian habitats. 2009. 39th International Conference on Environmental Systems (ICES), Hyatt Regency, Savannah, Georgia, USA, July 12 - 16.<br /> Jones, S.B., R.M. Estevez and D.A. Robinson. 2008. Mobile Soil Water Content Derived from Time Domain Reflectometry and an Open-Ended Dielectric Probe. ASABE Annual Meeting, Reno Nevada, June 21-24.<br /> Keller, T., M. Stettler, J. Arvidsson, M. Lamandé, P. Schjønning, M. Berli, and T. Rydberg, Stress propagation in arable soil: Determination and estimation of the concentration factor, 18th Conf. ISTRO. ISTRO, 2009, Izmir, Turkey.<br /> Koonce, J., D. Sada, M.H. Young, M. Stone, Z. Yu, Evaluating groundwater and surface water exchange in Travertine Spring, Death Valley, CA, using temperature coupled with soil and water chemistry and moisture content AGU Fall Meeting, December 1418, 2009, San Francisco, CA.<br /> Li, Y., K. Acharya, D. Chen, M. Stone, Z. Yu, M. Young, J. Zhu, D. Shafer and J. Warwick, Circulation and temperature stratification of Lake Mead under changing water levels, AGU Fall Meeting, December 1418, 2009, San Francisco, CA.<br /> Martin, M.A., F. San Jose Martinez, J. Caniego, M. Tuller, A. Guber, Y. Pachepsky, and C. Garcia-Gutierrez, 2009. Macropore structures of discretized X-ray CT of undisturbed soil columns and long rage dependencies. 1st International Conference "Challenges of Porous Media", Kaiserslautern, Germany, March 11-14, 2009.<br /> Meyer, W.J., M.H. Young, J.J. Miller, D. S. Shafer, S. Ahmad, Spatial and temporal variability of antecedent moisture content on model-generated runoff from a watershed, ASA-CSA-SSSA Annual Conference, November 2-6, 2009, Pittsburgh, PA.<br /> Meyer, W.J., S. Ahmad, M.H. Young, D.S. Shafer, J.J. Miller, K. Chief, A Multi-platform approach to examine spatial and temporal variability of antecedent moisture content on model-generated runoff from a watershed, AGU Fall Meeting, December 1418, 2009, San Francisco, CA.<br /> Miller, J., G. Dana, and T.G. Caldwell, Effectiveness of erosion-reduction techniques used in watershed restoration activities, 33rd IAHR 2009 Congress - Water Engineering for a Sustainable Environment, August 9-14, 2009, , Vancouver, Canada.<br /> Mirjat, M.S., and M. Tuller, 2009. Optimization of Zone Leaching for Salinity Control in Arid and Semiarid Regions. SSSA International Annual Meeting, Pittsburgh, PA, November 1-5, 2009.<br /> Mohanty, B.P. Estimating van Genuchten Soil Water Retention Parameters Using Remote Sensing. Soil Science Society of America Annual Meeting Abstract. 2009<br /> Mohanty, B.P. Physical Controls of Soil Moisture Across Space and Time Scales  A Grand Challenge Problem and Opportunity in Soil Hydrology for the next Decade. Soil Science Society of America Annual Meeting Abstract. 2009 <br /> Mohanty, B.P., and C. Joshi, Soil Moisture Time Stability in Two Hydro-climatic Regions. AGU Fall Meeting Abstract. 2009.<br /> Pollacco, J., and B.P. Mohanty, Can Hydraulic Parameters of a Physically Based Model be Identified by Time Series Soil Moisture Data? AGU Fall Meeting Abstract. 2009.<br /> Sakai, M., Jones, S.B. and M. Tuller. Numerical Evaluation of Heat Pulse Technology for Estimation of Evaporation Rates from a Subsurface Drying Front. 2009. AGU Fall Meeting Abstracts, San Francisco, CA, December 14-18.<br /> Sakai, M., S.B. Jones, and M. Tuller, 2009. Numerical Evaluation of Heat Pulse Technology for Estimation of Evaporation Rates from a Subsurface Drying Front. Eos Trans. AGU, 90(52), Fall Meet. Suppl., Abstract H33A-0848.<br /> San Jose Martinez, F., J. Caniego, F.J. Munoz, M.A. Martin, M. Tuller, A. Guber, and Y. Pachepsky, 2009. Singularity features of pore size distribution of structured soil columns. 1st International Conference "Challenges of Porous Media", Kaiserslautern, Germany, March 11-14, 2009.<br /> Sawatzky, D.A., F.X.M. Casey, N.E. Derby, S. Korom and X. Jia. 2009. Hydraulic Efficiency in Biofilm Affected Tile Drain. In Annual Meetings Abstracts [CD-ROM]. ASA, CSSA, and SSSA, Madison, WI. - Student Advisee<br /> Schaap, M.G. and P. Gallo, 2009. Measurement and Modeling on Flow Hydrodynamics in Crushed Basalt in Support of Constructed Hillslopes in Biosphere 2. AGU Fall Meeting, San Francisco, December 18, 2009, EP53C-0636.<br /> Schaap, M.G., Hydraulic Functions: The Good, The Bad and The Challenges. Invited Talk for Symposium--Application of Soil Physics to Resolving Environmental Problems: Honoring the Impact of Martinus Th. Van Genuchten, November 2, 2009.<br /> Schaap, M.G., M. Tuller, A. Guber, and Y. Pachepsky, 2009. Lattice Boltzmann Modeling of Macro-Porous Flow: Effects of Image Segmentation Algorithms and Comparisons with Observed Data. SIAM Conference on Mathematical & Computational Issues in the Geosciences, Leipzig, Germany, June 15-18, 2009.<br /> Seefeldt, S.S., D.L. Barnes, R. Ranft, W. Rhodes. 2009. Persistence of Triclopyr in Alaska Subarctic Environments. Presented at the annual meeting of the Weed Science Society of America, Orlando, FL, February 9-13.<br /> Shin, Y., B.P. Mohanty, and A.V.M. Ines, Combining SEBAL Model and NMCGA Algorithm for the Estimation of Effective Soil Hydraulic Properties. AGU Fall Meeting Abstract. 2009.<br /> Shrestha, S. F.X.M. Casey, D. Smith, H. Hakk, G. L. Larsen, and G. Padmanabhan. Fate of Glucuronide Conjugated Estradiol in Soil. Environmental & Water Resources Institute of ASCE (EWRI of ASCE) and the Asian Institute of Technology (AIT). Pathumtani, Thailand, on January 5-7, 2009.<br /> Sun, D., and J. Zhu, Averaging schemes of hydraulic properties in large scale heterogeneous soils, 2009 GSA Annual Meeting, October 18-21, Portland, OR.<br /> Sun, D., and J. Zhu, Effective soil hydraulic properties for transient evaporation in heterogeneous soils, AGU Joint Assembly, May 24-27, 2009, Toronto, Canada.<br /> Sun, D., and J. Zhu, Soil hydraulic parameters for evaporation in large scale heterogeneous soils, ASA-CSA-SSSA Annual Conference, November 2-6, 2009, Pittsburgh, PA.<br /> Sun, D., and J. Zhu, Soil hydraulic properties and large scale evapotranspiration in desert ecosystem, 94th ESA Annual Meeting, August 27, 2009, Albuquerque, NM.<br /> Sun, D., J. Zhu, M. Young, T. Caldwell, E. McDonald, Effect of canopy patterns on large scale water budgets in arid environments, AGU Fall Meeting, December 1418, 2009, San Francisco, CA.<br /> Tuller, M., and P. Iassonov, 2009. Sequential Segmentation for Correction of Intensity Bias in X-Ray CT Grayscale Images. SSSA International Annual Meeting, Pittsburgh, PA, November 1-5, 2009.<br /> Tuller, M., and Th. Gebrenegus, 2009. Polypropylene Fiber Amendments to Alleviate Initiation and Evolution of Desiccation Cracks in Bentonite Liners. Eos Trans. AGU, 90(52), Fall Meet. Suppl., Abstract H23F-1029.<br /> Vaz, C.M.P., P.R.O. Lasso, I.C. de Maria, P. Iassonov, and M. Tuller, 2009. Application of a Benchtop MicroCT Scanner to Determine Soil Pore Size and Aggregate Distributions at Different Scales and Resolutions. Eos Trans. AGU, 90(52), Fall Meet. Suppl., Abstract H23F-1031.<br /> Vaz, C.M.P., P.R.O. Lasso, I.C. de Maria, P. Iassonov, and M. Tuller, 2009. Estimation of Soil Water Retention Properties from X-Ray Microtomography Observations. SSSA International Annual Meeting, Pittsburgh, PA, November 1-5, 2009.<br /> Wang, C. and S.B. Jones. 2009. Evaluating Soil Water Content Sensors by Simulating High Clay Content Soils with Varied Relaxation- and Electrically Conductive-Dielectric Liquids. Spring Runoff Conference, Eccles Conference Center, Utah State University, Logan, UT, April 2-3.<br /> Wang, C., R.M. Estevez, C.M.P. Vaz and S.B. Jones. 2009. Quantifying the Impact of Soil Properties on the Performance of Electromagnetic Water Content Sensors. ASABE Annual Meeting, Reno Nevada, June 21-24.<br /> Weisbrod, N., and M.I. Dragila. 2009. Soil Cracks Intensify Soil-Atmosphere Gas Exchange. Soil Science Society of America Annual Meeting, Pittsburg, PA, November 2009.<br /> Wells, S.G., E.V. McDonald, T.G. Caldwell, M.H. Young, and K. Al-Quda, Role of desert pavement/soil development and hydrology on long-term landscape evolution in arid regions, International Union of Quaternary Research Conference on Paleohydrology, October 28-November 3, 2009, Hebrew University, Jerusalem.<br /> Young, M., L. Fenstermaker, and J. Zhu, Near-surface water content and carbon flux in biological soil crust, AGU Chapman Conference on Examining Ecohydrological Feedbacks of Landscape Change along Elevation Gradients in Semiarid Regions, 5  9 October 2009, Sun Valley, ID.<br /> Young, M., L. Fenstermaker, L., and J. Zhu, Dynamics of very near-surface water contents in an arid setting, ASA-CSA-SSSA Annual Conference, November 2-6, 2009, Pittsburgh, PA.<br /> Zhu, J., and D. Sun, Effect of spatial soil hydraulic properties on large scale evapotranspiration, AGU Joint Assembly, May 24-27, 2009, Toronto, Canada.<br /> Zhu, J., and D. Sun, Effective soil hydraulic properties for infiltration and redistribution in unsaturated zone, AGU Fall Meeting, December 1418, 2009, San Francisco, CA.<br /> Zhu, J., and M. Young, sensitivity of evapotranspiration estimates for semi-arid shrublands, 94th ESA Annual Meeting, August 27, 2009, Albuquerque, NM.<br /> Zhu, J., Capillary Pressure-dependent anisotropy of unsaturated layered soils, ASA-CSA-SSSA Annual Conference, November 2-6, 2009, Pittsburgh, PA.<br /> Zitnick, K., H. Hakk, F.X.M. Casey, T. DeSutter, N. Shappell and E. Khan. 2009. Effects of Liquid Swine Manure On Sorption of 17ß-Estradiol to Soil. In Annual Meetings Abstracts [CD-ROM]. ASA, CSSA, and SSSA, Madison, WI. - Student Advisee<br />

Impact Statements

1. All W2188 group members contributed to a reported 137 publications, including 3 book chapters and an additional 86 abstracts submitted for presentations. Members were involved in mentoring students and post-docs with 10 graduate students completing degrees.
2. Texas developed and calibrated a physically-based model to estimate water contents in fine-textured soils. The model corrects relative water content errors in excess of 10% associated with earlier, empirical calibrations and overcomes difficulties associated with EM soil water sensing under temporally- and spatially-variable field conditions.
3. UC-Riverside HYDRUS represents a capstone outcome of W2188. At present, HYDRUS addresses a variety of hydraulic, thermal, biogeochemical, microbial, and gaseous vadose zone processes for use in academia, state and federal institutions, and the private sector. In 2009, there were more than 5,300 unique downloads of this software and more than 800 registered forum users who share ideas and approaches. HYDRUS has become an essential part of soil physics courses taught around the world.
4. Kentucky developed new tools, devices, analytical methods and capabilities to quantify and monitor movement of agricultural contaminants and other materials from the vadose zone to ground water and to the atmosphere. Experimental results on field-scale solute transport suggest rainfall forecast and characteristics are important for consideration in surface application of salts and chemicals on crops and soils. Improved protection of soil and water resources and sustainability associated with energy production, water/irrigation management and mineral extraction activities are expected.
5. Washington continued development, improvement, and testing of the WEPP model which has enabled broad applications of WEPP for assessing soil erosion and determining remediation strategies on crop-, range-, and forest-lands within and outside the US. GeoWEPP has been used to support watershed management and wildfire mitigation in ID, WA, MT and CA. Online forest WEPP interface drew 5,000 users resulting in 180,000 predictions in 2008.

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Report Information

Participants

1. Barnes, Dave Univ. of Alaska, Fairbanks, AK
2. Berli, Markus Desert Research Inst., Las Vegas, NV
3. Bradford, Scott USDA Salinity Lab., Riverside, CA
4. Caldwell, Todd Desert Research Inst., Reno, NV
5. Chief, Karletta Desert Research Inst., Las Vegas, NV
6. Dragila, Maria Oregon State Univ., Corvallis, OR
7. Harter, Thomas Univ. of California, Davis, CA
8. Heinse, Robert (new member) Univ. of Idaho, Moscow, ID
9. Hopmans, Jan Univ. of California, Davis, CA
10. Horton, Bob Iowa State Univ., Ames, IA
11. Jacobsen, Jeff (W-2188 advisor) Montana State Univ., Bozeman, MT
12. Jones, Scott (Chair) Utah State Univ., Logan, UT
13. Kamai, Tamir Univ. of California, Davis, CA
14. Kelleners, Thijs (Secretary) Univ. of Wyoming, Laramie, WY
15. Kluitenberg, Gerard Kansas State Univ., Manhattan, KS
16. Knighton, Raymond USDA, Washington, DC
17. Mohanty, Binayak Texas A&M Univ., College Station, TX
18. Nieber, John Univ. of Minnesota, St. Paul
19. Nielsen, Don Univ. of California, Davis, CA
20. Ochsner, Tyson Oklahoma State Univ., Stillwater, OK
21. Shukla, Manoj New Mexico State Univ., Las Cruces, NM
22. Simunek, Jirka Univ. of California, Riverside, CA
23. Skaggs, Todd USDA Salinity Lab., Riverside, CA
24. Tuller, Markus Univ. of Arizona, Tucson, AZ
25. Twarakavi, Navin Auburn Univ., Auburn, AL
26. Warrick, Art Univ. of Arizona, Tucson, AZ
27. Wendroth, Ole Univ. of Kentucky, Lexington, KY
28. Yang, Liang (new member) Univ. of Texas, Austin, TX
29. Young, Michael Univ. of Texas, Austin, TX
30. Zhu, Julian Desert Research Inst., Las Vegas, NV
31. Zhang, Fred Pacific Northwest Nat. Lab, Richland, WA

Guests:
32. Amin, Mostofa Aarhus Univ., Denmark
33. Moradi, Ahmad Univ. of California, Davis, CA
34. Sakai, Masaru Utah State Univ., Logan, UT

Brief Summary of Minutes

Monday, January 3, 2011

8:50 am: Scott Jones, W2188 chair, welcomed the participants and explained the agenda for the meeting.

9:00 am Markus Tuller: Markus presented work on high-resolution micro computed tomography using benchtop scanners. Soil and glass bead samples of different sizes were scanned at different resolutions. An optimized scanning protocol was used to determine porosity and (preliminary) mineral density. Excellent image contrast (phase peak separation) allowed for direct multi-phase segmentation using a 3-D algorithm.

9:30 am Bob Horton: Bob briefly mentioned how he spent his 2010 spring semester sabbatical visiting three institutions in China. He went on to discuss soil evaporation measurements in a corn field using an 11-needle heat pulse sensor. He found that daily evaporation heat pulse estimates compared well with micro-lysimeter and Bowen ratio measurements. Subsequently, Bob discussed laboratory work to measure the water vapor enhancement factor and field work to assess nitrate leaching, biomass production, and CO2 emissions for different cropping systems. Finally, he discussed energy balance closure issues related to the depth of soil heat flux measurements.

10:00 am break

10:30 am Tamir Kamai: Tamir presented a web-based application of model and data analysis for the heat pulse probe where the web browser serves as the graphical user interface. Computational tools were developed in Python. Two methods have been implemented: (1) instantaneous infinite line source and (2) pulse infinite line source. Data analysis can be based on a time series fit or the maximum temperature rise. Both forward and inverse analysis can be conducted. The website may serve as a central location for the heat pulse probe community.

11:00 am Jan Hopmans: Jan briefly summarized a number of projects he has been involved in: heat pulse probe, carbon sequestration, micro-irrigation guidelines, and salinity effects on crops. He then went on to discuss the southern Sierra Critical Zone Observatory. The observatory consists of a number of nested watersheds at the transition of snow dominated and rainfall dominated systems. Spatial variability of soil texture and depth to bedrock were analyzed. Sensor arrays were used to study soil moisture dynamics under and in-between selected trees. Jan explained how Hydrus is used to describe the soil-tree coupling. Finally, Jan presented results from a detailed tree root survey where a complete root system was mapped.

11:30 am Thomas Harter: Thomas first mentioned his involvement in a water resources research special issue on sustainable groundwater in agriculture. Thomas then discussed his work on N leaching from large dairy operations in the Central Valley. In the southern portion of the Central Valley unsaturated zones can be deep due to extensive pumping of groundwater. Leaching below corrals, storage lagoons, and irrigated fields was sampled by taking deep soil cores. Thomas presented results for a series of water and soil quality parameters and discussed the underlying transformation and transport processes.

1:00 pm Ahmad Moradi: Ahmad, working with Tamir and Jan, presented his work on neutron imaging of water uptake by roots. He found that water content may decrease with distance from the roots. Also, the soil around the roots had different properties than the bulk soil. He then discussed future experiments to study root water uptake under differential soil water contents. Ahmad proposed to use a growth chamber where the plant has access to wet and dry soil regions separated by a vertical capillary barrier of coarse sand.

1:30 pm Binayak Mohanty: Binayak gave an overview of his work on soil hydrology across scales. Going from small to large spatial scales he identified soil texture, topography, land cover, and climate as the main drivers. Binayak then presented a multi-scale bridging model that uses a scaling parameter that is defined as a function of sand fraction, vegetation index, terrain slope, amount of precipitation, and scale ratio. He finished with an example of topography-based upscaling to predict streamflow for the Little Washita Watershed in Oklahoma.

2:00 pm Zong-Liang Yang (guest speaker): Dr Yang gave an overview of land surface modeling. He identified land use change, dust emissions, cold region hydrology, and volatile organic compounds as being relatively uncertain with regard to climate research. Dr Yang then gave a brief historic overview of land surface models culminating in the 2010 version of the Community Land Model. After defining the different land surface processes he went on to show some examples of soil moisture precipitation interactions. This was followed by a more in-depth look at the strengths and weaknesses of so-called 1st, 2nd, and 3rd generation land surface models. With regard, to model calibration, Dr Yang identified 3 needs: (1) data from pure biota, (2) understanding how to define the area average, and (3) making best use of remote sensing data. In the second part of his talk, Dr Yang focused on Community Land Model Version 4, which was released recently. He explained how land use is specified and provided details on the description of soil hydrology and soil temperature in the model. He finished, by showing examples of model validation using soil temperature, eddy covariance, river discharge, and satellite-measured water storage data.

3:00 pm break

3:30 pm Manoj Shukla Manoj first presented his work on root water uptake of Pecan trees. He used depth-wise soil moisture and temperature data in combination with Hydrus to quantify soil liquid water and vapor fluxes both with and without root water uptake. He conducted a sensitivity analysis of root water uptake with and without compensation. Manoj then proceeded with a different study on the effect of sodic wastewater application on soil water infiltration. Results shown included the spatial variability in saturated soil hydraulic conductivity and soil sodicity across the field site.

Tuesday, January 4, 2011

8:00 am Business Meeting: Scott Jones (Chair) opened the business meeting and asked for approval of the 2009 activity report and the 2010 meeting minutes. The group approved both the report and the minutes unanimously. Next up was new member nominations. Liang Yang (guest speaker from Univ. of Texas, Austin, TX) and Robert Heinse (Univ. of Idaho, Moscow, ID) were nominated. Both nominations were unanimously approved by the group. This was followed by nominations for the new W2188 secretary. Manoj Shukla and Tyson Ochsner were nominated. Tyson Ochsner was elected as the new W2188 secretary (Tyson accepted). Subsequently, next years meeting was discussed which will be held in Hawaii. Scott mentioned that Ali Fares (Univ. of Hawaii) has confirmed his willingness to help with organizing the meeting. The idea is to follow the W2188 meeting with a soil moisture sensing conference organized by Ali. Ray Knighton suggested to submit a $5000 proposal to USDA to support both meetings. There was some discussion on the W2188 meeting dates. Wed-Fri 4-6 Jan (Scott), Thu-Sat (Jirka), and Thu-Fri (Tyson) were proposed. Bob suggested having a field trip on Saturday. The sensor conference is scheduled for Mon-Wed Jan 9-11. Fifteen W2188 group members expressed interest in attending both meetings. With regard to our 2013 meeting, Tamir, on behalf of Jan, offered UC Davis as a meeting place. This received wide support from the group with 16 votes in favor. Tyson suggested that Oklahoma State Univ., Stillwater, OK could serve as a meeting place in the future.

8:30 am Jeff Jacobsen: Jeff mentioned that the W2188 multi-state research award nomination packet was not successful. In the western region a grape project won, while at the national level a chestnut project won. Review committee members expressed that the W2188 proposal was strong. There were no written review comments. Jeff thanked Scott, Markus, Ray, Mike, and Ole for putting the proposal together and suggested resubmission after some fine tuning with a stronger connection to stakeholders. A successful proposal would result in wide recognition and $15,000 that could be used for guest speakers. Deadline for resubmission is end of March.
Jeff inquired about future guest speakers (Jeff is paying for this year's speaker Liang Yang). Ray suggested that co-sponsoring the W2188 and soil moisture sensing conference in Hawaii would help in attracting USDA funds for guest speakers. It was also mentioned that we can exchange speakers between W2188 and the soil moisture conf. in Hawaii so that not all W2188 members have to speak during the W2188 meeting.
Last year, Bob asked Jeff about how multi-state funds are actually used by the different experiment stations. This year, Jeff reported on his survey of experiment stations with 12 out of 14 responding from the western region. The results: 10 stations use the funds for faculty salary, 9 to pay for travel, 6 for staff salary, 6 for operations, 5 for students, and 1 for postdocs.
During Jeff's presentation there was some group discussion on the length and format of the meeting. Should the meeting be 2 or 3 days? Ole argued in favor of keeping the meeting 3 days, with reference to an historic trend of making the meeting shorter and shorter. Mike suggested that speaking time should be limited and discussion time should be increased. One way of doing this would be to limit slide numbers and to focus on objectives and future plans (Mike). Scott suggested that shorter presentations would require clear instructions.

9:00 am Ray Knighton: Ray briefly summarized the current AFRI setup with 5 challenge areas and the foundational program. AFRI is now funding larger more focused research and has moved away from funding discipline oriented research. The air quality and soil processes categories for example are no longer available. The RFA for the foundational program will be released this Friday. Feedback suggests that the research community does not like the new setup and wants to move back to more discipline oriented research where there is something for everyone, despite the low funding rates.
The RFA's for the challenge areas have been written up and are currently awaiting approval. The idea is to release the challenge RFAs at 2-week intervals after the foundational RFA has been published. The challenge areas will be the same as last year but less funding is likely available due to budget constraints. Individual RFA's may be retracted if no funds are available. Ole asked about stakeholder feedback to restore funding for soil processes. Ray responded that formal stakeholder input sessions were held last year and that the soil processes program is not likely to return. Funding for soils is now available through the climate change RFA but must be tied to the larger climate topic. Ray stressed that last year most proposals were big (5M$ over 5 years) and that smaller proposals would be appreciated. Don asked about the availability of discipline oriented research. Ray suggested NSF. Feedback from the experiment stations on the current AFRI approach appears to be mixed, with directors liking the new direction (Ray), and directors being worried about the decrease in formula dollars (Jeff). Other programs that might be of interest this year: (1) the specialty crop research initiative (15M$/yr) and (2) the 406 water quality program (12M$).
Finally, Ray gave an update on the reorganization of NIFA into for sub-institutes (bioenergy, climate, environment, and plant & animal production). All personnel will be dispersed over these topical units. Each institute will have a director and a principal scientist. The principal scientist may remain connected to his/her institution but has to be physically in Washington, DC. Thomas asked about the upcoming farm bill and the large emphasis on crop management with little attention to emissions. Ray responded that (1) little research is actually being adopted by producers, (2) the bill is dominated by commodity crops, and (3) emissions from cereals, poultry, and southern conifers are included in the climate change RFA.

9:30 am John Nieber: John first summarized his work on the sources of sediment in Minnesota rivers and streams. Results show that fields contribute ~30 % and that near channel sources (bluffs, ravines, and stream banks) need more attention. Of these, bluffs appear to be the largest source of sediments. Research on the increased contribution of near-channel sources to sediment loads is ongoing. Next, John discussed work on the differential response of Minnesota watersheds to climate change. The effects of land use change and water withdrawal are also considered. Streamflow has increased mainly in the south due to vegetation change. The SWAP model will be used to evaluate the effect of vegetation change on groundwater recharge and streamflow.

10:00 am Mike Young: Mike in his capacity as S1 chair mentioned the following two symposium proposals for the SSSA annual meeting in San Antonio: (1) emission of regulated and greenhouse gases: measurement, technology, monitoring, and policy and (2) advances is vadose zone hydrology: contributions of Glendon Gee. He went on to discuss a possible different setup for S1 poster presentations in which posters are only up for a brief period. Mike also asked for input on how to improve the visibility of student contributions (with awards) and how to make soils more forward looking. Program enhancement dollars are available for awards.

10:05 am break

10:30 am Jirka Simunek: Jirka gave an overview of the latest Hydrus developments. The graphical user interface for HP1 (Hydrus + Phreeqc) has been simplified so that it is easier to understand for new users. A report with examples has been posted on the Hydrus website. Jirka is working with different groups to get them going with HP1. The Hydrus model was downloaded 5000 times last year. A new fumigant model has been added to Hydrus. In 2010, Hydrus received a favorable review in the journal Ground Water. The Hydrus 2d/3d professional version update should be done this year and includes general 3d geometries and more flexible boundary conditions. In 2010, Hydrus short courses were organized in Colorado, Netherlands, Argentina, and South Africa. Four new courses are planned for this year. Finally, a book entitled Soil Physics with Hydrus came out this year.

10:45 am Mostofa Amin: Mostafa, visiting with Jirka, presented his work on the simulation of contaminant redistribution due to soil-injected pig slurry manure. Mostafa is particularly interested in the fate and transport of viruses and bacteria. Experimental data from 2 research sites in Denmark are simulated using Hydrus 2-D. Model performance indicators for soil moisture, chloride, ammonia, nitrate, phage, E. coli, estradiol, and estrone distribution were shown.

11:00 am Maria Dragila: Maria presented ongoing work on the impact of salinity and heterogeneity on soil evaporation and on the mechanisms controlling subsurface salt deposition. Laboratory studies were conducted on soil columns with fine sand, coarse sand, and with both fine and coarse sand. A mathematical model was developed to calculate the effect of salinity and heterogeneity on evaporation. CT scans were used to image the top of the columns. Maria concluded that saline evaporation requires a redefinition of the 3 classical evaporation stages. She also concluded that salt will deposit in the smaller pores in heterogeneous media, leaving the larger pores open for vapor transport.

11:30 am Tyson Ochsner: Tyson discussed his work on multi-scale monitoring of soil moisture. At the large scale, he is working on Oklahoma Mesonet data to monitor drought by measuring plant available water. Heat dissipation sensor water potential estimates are converted to water content using soil water retention data. The resulting plant available water estimates are compared to measured data from soil cores. Phase 2 of this project includes the assessment of spatial variability in plant available water across Oklahoma. At the small scale, Tyson is involved in an in-situ sensor testbed in grassland to evaluate cutting edge soil moisture sensing techniques.

1:00 pm Julian Zhu: Julian presented his work on the sensitivity of unsaturated flow and contaminant transport to correlated parameters. Multiple realizations of parameters were used to rank the relative importance of individual model input parameters. Example calculations were conducted for Yucca Mountain. Depth-wise standardized regression coefficients were calculated when input parameters were independent. For correlated parameters, the contribution of individual input parameters to output uncertainty was more difficult to determine. Next, Julian discussed his work on the effect of evapotranspiration on the fractal dynamics of groundwater systems. Groundwater observation well data were used in a detrended fluctuation analysis.

1:30 pm Dave Barnes: Dave first discussed his work on groundwater flow and contaminant transport in oil field gravel pads in Alaska. Polygon patterned ground due to ice wedges may route water below the pads in continuous permafrost regions. In discontinuous permafrost regions the groundwater flow is strongly influenced by the spatial distribution of the permafrost. Next, Dave presented work on PCE vapor intrusion of buildings in cold regions. Both diffusion and advection play a role. The PCE concentrations are highest during summer. The concentrations show a positive correlation with soil temperature at 1 m depth. Measured and predicted indoor air concentrations were shown for different combinations of soil gas flow rate and building air exchange rate.

2:00 pm Robert Heinse: Roberts talk focused on the measurement of soil pipe networks in forested hillslopes using electrical resistance tomography. The soil pipes play an important role in the watershed response to water input. The pipes are characterized pre-burn and post-burn. The pre-burn measurements indicate that below-ground portions of stumps, dead roots, and possibly soil pipes can be identified. Robert then went on to summarize some of his work in (1) archeogeophysics at a former Japanese internment camp, (2) the climate impacts of municipal greening, and (3) the effects of historic terracing on soil properties in forests.

2:30 pm Scott Bradford: Scott presented work on the transport and retention of colloids, micro-organisms, and colloid-associated contaminants in porous media. Part of his work is done at the pore-scale, developing a fundamental understanding of the physics and chemistry involved in the transport and retention. The other part is done at the macroscopic scale to better understand the time and concentration dependent filling of retention sites. Chemical interactions and retention hysteresis are also studied at the macroscopic level using column experiments at different ionic strengths. At the field-scale, Scott is using Comsol to study surface and subsurface transport of pathogens in buffer strips.

3:00 pm Break

3:30 pm Todd Skaggs: Todd first presented his work on critical path analysis using cylindrical and slit-shaped pore networks. He developed new critical path results by adding a coefficient. Results from Monte Carlo calculations for 3-d networks showed improvement over the classical critical path model. Todd then went on to discuss new work to measure soil moisture effects on the diurnal variation of diazinon volatilization. A large vertical soil column was instrumented with temperature, moisture, potential, and heat pulse probes. Evaporation is measured directly by placing the column on a balance. The experiment will be redesigned in the coming weeks.

4:00 pm Gerard Kluitenberg: Gerards talk focused on his development of a new semi-analytical solution for the dual-probe heat-pulse method that accounts for the presence of the probe. Both probes are treated as perfect conductors. First a solution is developed for the heater probe with finite diameter, then a solution is developed for both the heater and thermistor probes. Derivations in the Laplace domain are followed by numerical inversion using the Stehfest algorithm. Results for dry sand, wet sand, and water are compared to finite element model solutions. The comparison is good with a slight time shift due to epoxy not being a perfect conductor. The new solution should eliminate overestimation of heat capacity and water content in dry media as is frequently observed using the line source solution.

4:30 pm Thijs Kelleners: Thijs presented his work on the measurement and modeling of CO2 production and transport in rangeland soils. A numerical soil water flow, heat transport, and CO2 transport model was calibrated by optimizing the soil profile CO2 production using an inverse algorithm. The model performance was best for soil temperature, and poorest for ecosystem respiration. Measured depth-wise soil water content, temperature, and CO2 concentration were also used directly to calculate depth-wise soil CO2 production and flux.

Wednesday, January 5, 2011

8:00 am Fred Zhang: Fred discussed his work on instrument performance for long-term deep vadose zone monitoring in Hanfords radioactive tank farms. The work focused on the T tank farm where a surface barrier consisting of compacted soil, geotextile fabric, and polyurea liner was installed to limit downward migration of a radioactive plume from a 1973 leak. Soil water content (capacitance probe and neutron probe), and water potential (heat dissipation sensor) were monitored to assess the soil water regime with and without the surface barrier. The heat dissipation sensors performed well, requiring almost no maintenance. The capacitance sensors had issues due to corrosion and loose contacts. The neutron probe gave reliable data but needed to be operated manually.

8:30 am Masaru Sakai: Masaru, working with Scott, presented his work on the numerical evaluation of subsurface soil water evaporation derived from the sensible heat balance. Synthetic data were generated for sand, silt, and silty clay by simulating liquid water, water vapor, and heat transport using Hydrus-1d with constant and diurnal atmospheric boundary conditions. The generated data were subsequently used to evaluate subsurface evaporation as determined by the heat-pulse method using a penta-needle probe. Results indicated that improved evaporation estimates can be obtained by minimizing the near-surface undetectable zone and by incorporating depth-specific thermal conductivity.

9:00 am Ole Wendroth: Oles presentation focused on soil water content behavior in internal drainage experiments. He used a joint space-time state-space approach to improve field soil hydraulic properties estimates. The idea is to describe the process of soil water redistribution in the temporal domain while updating temporal predictions in the spatial domain. The new method will be tested on data from 25 Oxisol profiles from Brazil. The spatial domain module is completed while the time domain module is in progress. Finally, Ole briefly mentioned the completed theses of three of his graduate students.

9:30 am Todd Caldwell: Todd presented results from 3 of his projects. His work on soil hetergeneity in arid shrublands showed that saturated hydraulic conductivity decreases as the soil ages and that the reduction in canopy-interspace conductivity is due to abiotic processes. His work on hydraulic gradients and dust emissivity along a Playa to Distal fan transect using a portable in-situ wind erosion lab showed that the Playa fringes had the highest dust emissions. Finally, Todd summarized ongoing work on global military operating environments where soil sensors are used to assess the soil environment in support of military operations and testing.

10:00 am Break

10:30 am Navin Twarakavi: Navin discussed a stochastic-experimental approach to study the effect of macropores on water flow and solute transport. In particular, he is looking at macropore development by Mole Crickets. Of particular interest are macropore size distribution and connectivity under saturated and unsaturated conditions. Navin presented laboratory experiments with artificial macropores in glass beads to study solute breakthrough in saturated systems. He is also interested in the effect of macropore coating on water flow and solute transport.

11:00 am Markus Berli: Markus presented work on the unraveling of rhizosphere physics using X-ray mircotomography. Roots and the surrounding soil are imaged non-destructively. Segmented images were used to construct a finite element mesh for soil moisture distribution calculation around the root. Separately, deformation of inter-aggregate pores due to root growth was simulating using COMSOL. Markus is currently considering going back to simpler geometries in order to validate the finite element model calculations.

11:30 am: Scott Jones closes the meeting.

Respectfully submitted,

Thijs J. Kelleners
2010 W2188 Secretary

Accomplishments

Short-term outcomes<br /> <br /> W2188 members mentored 28 MS students, 33 PhD students, and 11 Postdocs. They graduated 8 MS students, 5 PhD students, and 1 Postdoc. A total of $7,032,000 in external grants was reported. Arizona developed a new algorithm for multiphase segmentation of X-Ray CT data of porous media with potential for real time segmentation and applicability in biomedical research. Arizona also showed that 3-D numerical simulations predict liquid behavior in greenhouse substrates reasonably well and can be used to optimize irrigation frequency and discharge rates for typical growth bags. Idaho imaged soil pipes formed by the combustion of tree roots on forested hillslopes as part of efforts to better quantify available water resources. Electrical resistivity tomography (ERT) is used to measure and quantify soil pipe existence, depth, geometry and connectivity. Data have been collected at three sites (625 points each) as well as EMI maps generated prior to a prescribed burn in late October. Idaho participated in an archeological survey of the former WWII Japanese internment camp near Kooskia. Geophysical overview maps were generated and a detailed 3D GPR survey of three sites was made. The aim was to identify former internee gardens. A new research project was started on Microclimatic Impacts of Green Spaces. This study will provide multiple scale metrics for addressing and responding to climate change and energy efficiency issues. Work continued on the use of time-lapse ERT measurements to characterize snowmelt fluxes and infiltration patterns linked to vegetation structures together with Scott Jones (USU). Work continued on the use of geophysics to characterize mine tailings. A statistical co-kriging methodology was developed to map slurry deposits from electric and electromagnetic surveys. Iowa constructed a new 11-needle heat pulse sensor to further test the heat pulse method of measuring soil water evaporation with time and depth. The sensor provided accurate measurements of soil water evaporation in a corn field. Low connectivity of intragranular pores results in scale-dependence of intragranular accessible porosity, tortuosity, and diffusivity. Through use of a pore network model, with diffusion modeled using random walks, it was shown that in a system with low connectivity, intragranular pores can be treated as a percolation problem. A new method was developed for determining soil thermal vapor enhancement factors. The vapor enhancement factor was shown to be soil texture dependent, and it should be measured for specific soils. The soil, water, and air environmental impacts of various ligno-cellulosic biomass producing cropping systems was determined. New Mexico collected and analyzed data and results were shared with the wastewater authorities for designing better wastewater irrigation techniques. Further analysis of soil and water samples is underway. Oklahoma submitted a grant proposal to the Oklahoma Water Resources Research Institute. The proposal was successful, providing $50,000 in new research funding. This work also resulted in an oral presentation at the Oklahoma Water Resources Research Symposium. The presentation served to inform ~100 stakeholders about the potential to use Mesonet for drought monitoring. The work also led to the creation of a new cooperative project with USDA-ARS funded at $15,000 per year. The objective of that project is to create an in situ sensor testbed for evaluating existing and emerging soil moisture sensing technologies. Oregon improved understanding of fundamental processes controlling saline evaporation from heterogeneous porous media. This understanding will benefit not only the soil science community, but is applicable in many areas of material sciences including construction, engineering, and protection of architectural monuments. UC Davis (Hopmans) continued development of (1) multi-functional soil sensors for soil moisture and nitrate that may lead to easy-to-use and low-cost soil moisture sensors based on the heat pulse concept; (2) a wireless soil moisture network in a remote forested ecosystem; (3) new root water and nutrient uptake models that allow for compensated water uptake and passive and active nutrient root uptake. The initial findings of (3) were instrumental in obtaining a new grant from BARD that will also investigate root water and nutrient uptake mechanisms. The workgroup on leaching requirement under saline soil conditions concluded that the present guidelines based on steady-state analyses over-estimate the negative consequences of irrigating with saline waters. This error is particularly large at low leaching fractions. This is a fortuitist finding because irrigating to achieve low leaching fractions is desirable for the purpose of reducing the transport of chemicals that degrade groundwater quality and also provides for a more efficient use of limited water supplies. The feasibility of using saline waters for irrigation is also enhanced. UC Riverside shifted focus from water quantity issues towards water quality. Progress was made on: (i) geochemical modeling, (ii) development and application of models capable to consider preferential/nonequilibrium flow and transport, (iii) application of numerical models to evaluate various micro-irrigation and fertigation schemes, (iv) transport of various contaminants, (v) developing and applying models for coupled transport of water, vapor and energy, and (vi) development of new website for HYDRUS models. The HP1 model that resulted from coupling of the flow and transport code HYDRUS with a geochemical model PHREEQC developed by USGS can simulate low-temperature biogeochemical reactions in water, soil and ground water systems including interactions with minerals, gases, exchangers, and sorption surfaces, based on thermodynamic equilibrium, kinetics, or mixed equilibrium-kinetic reactions. Version 2.0 was released and the HYDRUS GUI upgraded so that it can fully support HP1. Training was provided in using HP1 in Utrecht, the Netherlands, and Kruger National Park, Skukuza, South Africa. Existing models capable of simulating preferential flow and transport using various dual-porosity and dual-permeability models were applied at both laboratory and field scales. Numerical models were used to analyze various micro-irrigation schemes involving fertigation. The distribution of salinity under a drip irrigation system was simulated and compared to experimental data. The HYDRUS-1D model was applied to simulate the transport of bacteria and colloids. Models that consider simultaneous movement and transport of water, vapor, and energy, including the mass and energy balance at the soil surface were developed and applied. The website for HYDRUS and related models was improved. This website offers new tools, including discussion forums, FAQ, public library of projects, references, etc. Wyoming continued automated monitoring of soil-state variables such as water content and temperature in irrigated fields, dryland cropped fields, rangeland, and forest ecosystems as part of several ongoing projects. A numerical soil water flow, heat transport, and CO2 transport model was expanded to include the Ball-Berry description of leaf stomatal conductance and photosynthesis.<br /> <br /> Outputs<br /> <br /> W2188 members (co-)authored 67 journal articles, 1 book, 2 book chapters, and 62 abstracts in 2010.Arizona developed an advanced Bayesian image classification algorithm based on Markov Random Fields (MRF) for 3-D segmentation of X-Ray CT data of porous media. This algorithm can be directly applied to segment reconstructed multiphase images, eliminating the need for dual-energy or wet/dry scans and associated image alignment and subtraction analysis that are commonly applied in synchrotron Micro-CT. To speed up segmentation of large 3-D datasets the MRF algorithm is implemented in CUDA" to run on a NVIDIA® Tesla" desk side GPU computing systems. The algorithm is expanded for real time segmentation and applications in biomedical engineering. Motivated by recent advances in Micro-CT, a SkyScan® 1172 benchtop Micro-CT system (SkyScan, Belgium) was evaluated and calibrated. This was a collaborative project with Carlos Vaz from EMBRAPA, Brazil. It was found that with proper scanning protocol, the evaluated scanner provided excellent data that are at least of the same quality as data obtained with synchrotron-based systems. For multiphase systems excellent contrast between aqueous and gaseous phases was achieved when 1% sodium iodine solution or tab water were used. Idaho developed and taught a new course on Environmental Geophysics. This graduate-level course consists of two lectures per week and weekly laboratory sessions. Laboratory sessions alternated between field-data collection using geophysical instrumentation, and data processing and interpretation in the computer lab. Students were further introduced to the use of Matlab, and were given a compendium of scripts for future use. Collaborations with USU (Scott Jones) and UA (Markus Tuller) on space soil physics and mine tailing re-cultivation continued. In addition, collaboration has been established with NMT (White) and UNR (Saito) on the development of novel approaches to identify triggers of drastic environmental change. Kansas conducted a laboratory experiment to study the effect of probe deflection on thermal conductivity estimates using the dual-probe heat-pulse (DPHP) method in collaboration with UC Davis (Hopmans). It was concluded that estimates of thermal conductivity obtained with the DPHP method are largely unaffected by changes in probe spacing and other errors resulting from inward or outward deflection of the heater and temperature probes. In collaboration with John Knight (Queensland University of Technology, Brisbane, Australia) and California (Hopmans) a new semi-analytical solution was derived to account for the finite diameter and finite heat capacity of the probes. The new theory allows for the possibility of using more robust sensors with probes of larger diameter. In collaboration with California (Hopmans), laboratory experiments are performed to evaluate the performance of a robust DPHP sensor for measuring soil water content. In a separate study, the hydrologic balance of a claypan soil was quantified and the effect of tillage on water balance components determined. It was part of an ongoing project in Labette County, Kansas, in which no-till and chisel tillage plots had been maintained since 1995. A sorghumsoybean rotation was initiated in 2003, with both crops grown each year in a randomized complete block design. The water balance for the full growing season was not significantly affected by tillage, despite the fact that the tillage treatments had been in place for more than 10 years. Drainage from the claypan soil was negligible. Work on the estimation of ground-water savings achieved through Salt Cedar control is being conducted in collaboration with J. J. Butler, Jr., and D. O. Whittemore of the Kansas Geological Survey. The primary objective is to use water-table fluctuations to estimate the impact of various salt-cedar control activities on the ground-water resources of the Cimarron River alluvial aquifer at a site in Clark County, Kansas. Application of control measures began in March 2005 and is continuing. The relative ground-water savings gained through control activities is being estimated with a ratio method specifically developed for this project. In related work, efforts to develop analytical solutions for strip-sinks with periodic forcing are ongoing. These solutions are being developed to gain insight into spatial variations in water-table fluctuations in vegetated riparian zones. Kentucky submitted a report to the Kentucky Small Grain Growers Association entitled: Winter Wheat Development, Grain Yield and Soil Water and Nitrogen Dynamics in a Farmers Field in Western Kentucky. New Mexico submitted an annual completion report to WRRI. One manuscript was submitted for publication to a peer-reviewed Journal. Research was presented at the Water Conference at Socorro and at the Soil Science Society America Conference at Long Beach. North Dakota completed a reconnaissance of estrogen at a farm. Soil cores were taken near manure sources, which are potential sources of estrogens. Also, cores were taken in two fields before and after manure had been applied. Laboratory soil batch experiments were used to identify the effect of manure-derived colloidal (COC) and dissolved organic carbon (DOC) on the binding of estrogen to soil. Additionally, soil batch laboratory experiments with sulfate conjugates of estrogens were conducted to identify the potential of sulfate conjugates of contributing estrogens to the environment. Soil column experiments were conducted in which water was transferred through the column, then a sulfonamide antibiotic was applied and transported through the column. The experimental results of the column transport experiments were modeled. As a laboratory classroom experience, field measurements were made near a roadside to identify Hg concentrations as affected by automobile traffic. A new technique to simultaneously identify and quantify, at low concentrations, 14 sulfonamide antibiotics in various environmental matrices (i.e., water, manure slurry, and soils) was developed. Additionally, two methods to synthesis sulfate and glucuronide 14C radio-labeled 17beta-estradiols were developed. Field experiments were conducted to identify the effect of manure composting on the concentration of estrogens in the manure. An extension publication was completed to disseminate information about how to use multiple years of crop yield data to develop zones for prescribing soil nutrients for precision agriculture. Oklahoma measured soil water retention characteristics to facilitate monitoring of plant available water via the Oklahoma Mesonet. Sampling was completed at every accessible Mesonet site, resulting in over 1000 soil samples. Laboratory measurements have been completed for ~500 of these samples. A computer program has been written for the Mesonet system resulting in preliminary maps of plant available water across the State. UC Davis (Harter) organized a number of short courses including a two-day introductory course on Groundwater and Watershed Hydrology and a three-day short course on Groundwater Flow and Transport Modeling. Supporting material for these short courses is available at http://groundwater.ucdavis.edu. UC Davis organized and chaired a first International Conference Toward Sustainable Groundwater in Agriculture  Bringing together Science and Policy near San Francisco in June 2010. The conference had 70 invited speakers and over 130 oral presenters with nearly 300 in attendance. The interdisciplinary conference highlighted the broad array of technical, management, and regulatory issues at the groundwater-agriculture interface and brought together scientists, managers, and policy makers from around the globe. A conference website and post-conference website http://ag-groundwater.org was developed. A special issue in Water Resources Research on the conference theme is in the works. UC Davis (Hopmans) obtained a patent: 1. Tuli, A., J.W. Hopmans, T. Kamai, and B.D. Shaw. 2009. In-situ soil nitrate ion concentration sensor. US patent application serial no. 12/267,895. Pub. No.: US2009/0166520 A1. A new course on environmental monitoring was developed. The environmental monitoring course includes sections on sensors and wireless techniques. Collaboration occurred with UCR (Simunek) and KSU (Kluitenberg), continuing the development of alternative laboratory and field methods for the estimation of soil physical properties using inverse modeling and parameter optimization across spatial scales. In addition, recent BARD funding made possible the collaboration with UCR (Simunek) on development of innovative approaches to model the compensated and active uptake of water and nutrients by plant roots. Collaborations are ongoing with various UCs (Irvine, Merced, Berkeley, Santa Barbara) through the CZO project, and with companies like Decagon Inc. to improve soil moisture measurement techniques. In another study, the multi-step outflow experiment for estimation of soil hydraulic properties was modified, largely simplifying laboratory procedures and reducing costs and time. Whereas values of saturated water content, qs, and saturated hydraulic conductivity, Ks must be measured independently, the remaining functional parameters are estimated using inverse solution of a transient drainage experiment using multiple suction steps and a hanging water column, with drainage outflows measured during drainage. A 6-person team completed a position paper on the need of improved guidelines for managing soil salinity and crop salt tolerance under micro-irrigation conditions. With colleagues at Arizona State University and others, a retrospective was written on the impacts of water developments in the southwestern US, funded by NSFs NCEAS (National Center for Ecological Analysis and Synthesis), on the occasion of the 25th anniversary of the book Cadillac Desert by Marc Reisner. The analysis provides strong scientific support for many of Reisners claims, except the notion that reservoir storage is imminently threatened by sediment. More broadly, it was estimated that the equivalent of nearly 75% of streamflow in the Cadillac Desert region is currently appropriated by humans, and this figure could rise to > 84% under a doubling of the regions population. The analysis provides recommendations on how to achieve a reduction in region-wide human appropriation of streamflow to a target level of 60%. Utah launched a new website for the TW Daniel Experimental Forest (http://danielforest.usu.edu) June 14, 2010. The website provides information regarding current weather conditions at the site, a map indicating its location, details about the site history, historical data download, outlines of research objectives, a list of 28 participants (faculty, staff and students) and a picture gallery. Major features of the website include a detailed data storage archive available for download and viewing online. We also worked on development of analytical tools to process dense eddy covariance data to determine water and carbon fluxes at the site. Utahs exploration of novel fluid flux determination approaches included theoretical as well as experimental paths. Numerical modeling exercises were continued to understand and test the energy balance involved in using heat pulse measurements for subsurface evaporation estimation. Numerical simulations were carried out to demonstrate the capabilities of the heat balance approach to subsurface evaporation estimates. A master student was recruited to continue work on the subsurface evaporation project. An updated sensor design includes the possibility to use the sensor in assessment of subsurface evaporation (USDA-funded project with Markus Tuller at UA). An array of heat pulse sensors are being developed for this application with the new boards under testing. Wyoming Soil moisture and temperature dynamics in dryland winter wheat fields in southeastern Wyoming were analyzed. Results showed that the traditional 14 month-fallow period used is inefficient in storing water. Maximum fallow efficiency was 14 %, indicating that only 14 % of the fallow period precipitation is stored in the soil. A numerical soil water flow, heat transport, and CO2 transport model was calibrated for a rangeland soil in southeastern Wyoming. The calculated annual carbon budget yielded a gross primary production of 267, an ecosystem respiration of 215, and a net ecosystem exchange of 52 g Carbon m-2 yr-1, indicating that the rangeland acted as a carbon sink during 2009-2010. Automated sensor data for the rangeland soil were also used to calculate depth-wise soil CO2 production and transport. Results showed that a relatively fine-textured soil layer at 7.5-15 cm depth produced the most CO2.<br /> <br /> Activities<br /> <br /> Arizona continued work on geophysical characterization of mine tailings in collaboration with Scott Jones (USU) and Robert Heinse (UI). The ability to sustain native vegetation on inactive mine tailings mitigates numerous environmental issues such as mass movement due to wind and water, leaching of hazardous chemicals, as well as aesthetic concerns. To develop strategies for optimizing hydrological conditions in mine tailings in the arid Southwest electromagnetic induction (EMI) surface surveys are applied to characterize spatial heterogeneity of physical and mineralogical tailings properties. Interesting correlations were found between EMI measured resistivity, texture and mineralogical composition of the tailing material. Experimental and numerical studies continued to optimize root zone fluid fluxes in novel greenhouse substrates. In 2010, comprehensive laboratory experiments were conducted under well-controlled initial and boundary conditions with foamed glass, a relatively new greenhouse substrate. It was shown that HYDRUS 3-D is capable of predicting observed behavior reasonably well, and can be used to optimize irrigation frequency and discharge rates for typical growth bags. Work was conducted on physicochemical controls on initiation and evolution of desiccation cracks in bentonite-sand liners by means of X-ray CT and stochastic modeling in collaboration with Teamrat Ghezzehei (UC Merced). Idaho chaired a session on 'characterizing soil moisture dynamics and plant-soil-water interactions' with co-chairs Nigel Crook (Stanford) and Tyson Ochsner (OSU) at the 2009 Fall Meeting of AGU. Idaho co-organized a session on 'detecting thresholds of ecosystem resilience in a changing climate' together with Amanda White (NMT), Li Dong (UNM), and Caiti Steele (USDA-ARS) for the 2010 Fall Meeting of AGU. Responsibilities included proposing, advertising and reviewing submitted abstracts. Kentucky chaired the Precision Resources Management Committee, College of Agriculture, Univ. of Kentucky. Program development and review of PRM proposals was undertaken. In addition Kentucky served as associate editor for Soil Science Society of America Journal and Vadose Zone Journal, and as editorial board member for Soil and Tillage Research and Journal of Plant Nutrition and Soil Science. In 2010, 46 manuscripts were reviewed. New Mexico organized field trips to conduct in-situ infiltration tests and collect soil and water samples. North Dakota returned from a sabbatical in July 2010 after working in Wexford Ireland with Dr. Karl Richards in Teagasc at their Agricultural and Environmental Research Group at Johnstown Castle. Oklahoma completed soil sampling for the Mesonet project and generated prototype maps of plant available water across Oklahoma. Bioenergy cropping systems field experiments were initiated in five locations. SMAP In Situ Soil Moisture Sensor Testbed was initiated. Finally, field experiments were conducted to determine impacts of crop residue harvest on soil properties. Oregon did laboratory work to investigate the role of internal boundaries on evaporation and salt deposition processes and fieldwork to investigate the role of heterogeneity on location of salt deposition. Three graduate students working on various aspects were mentored or co-mentored. Graduate courses on soil physics and undergraduate hydrology were taught. UC Davis (Harter) supported irrigation and water district personnel, local agency personnel, state and federal agency personnel, farm advisors, farm industry representatives, environmental stakeholders, and county extension directors on issues regarding groundwater use and protection in rural and agricultural areas. The integrated basic and applied research program can be divided into three categories: A) groundwater resources modeling, B) understanding of contaminant transport at the laboratory and field scale, and C) basic and applied research on modeling flow and transport in heterogeneous systems. The program includes a rigorous assessment of the impacts of agricultural water management practices on short-term and long-term land subsidence in the Tulare Lake Basin of California. Investigations are ongoing on potential water management scenarios to improve streamflows in the Scott River Valley, where the Scott River is one of the key salmon spawning grounds in the Klamath River system. A groundwater-surface water model was developed that will be calibrated for the 1991-2009 period and used for evaluating conjunctive use management options in the Scott River Valley. At the surface watergroundwater interface, vernal pools (seasonal wetlands) are a much smaller, but equally important ecological system of which the hydrological functioning is poorly understood. Several vernal pool sites in the Central Valley were instrumented to investigate hydrologic fluxes and biogeochemical processes in the pools. Utah made 3 international visits, one to China under USUs International development project, a second to Denmark as an invited speaker and participant in a SOIL FUTURE research conference, and the third to Israel. The China Agricultural University was visited in June. The main goal of the trip was to visit Yurui Sun, one of the leading experts worldwide on electromagnetic instruments for agricultural application. The US embassy in Beijing was visited to learn more about NSF funding in China. Utah was invited to the Embassy meeting by another collaborator, Liming Yang, who is coordinating work with USU and the UTAH-TAIHU Institute. Utah is among a large group of collaborators on a Danish National Research Foundation proposal titled, Center of Excellence for Soil Functional Architecture: SOIL FUTURE. A travel grant was used to support a visit to Israel in July 2010, aimed at developing research collaboration with Dr. Shmulik P. Friedman and Grisha Communars (Agricultural Research Organization, Volcani Institute). A proposal was submitted to the Binational Agricultural Research Foundation (BARD). Wyoming participated in ongoing data collection for the following multi-investigator projects at the University of Wyoming: (1) Soil water and nutrient dynamics in dryland wheat fields in southeastern Wyoming; (2) crop-range-livestock farm research in southeastern Wyoming; and (3) runoff generation in snow-dominated mountainous forest ecosystems in southeastern Wyoming. A new multi-investigator project was started on Wyoming rangeland drought issues using existing data from a state-wide soil moisture network (Agricultural Experiment Station funding).<br /> <br /> Milestones<br /> <br /> Kentucky derived the spatial range of representativity for bromide tracer concentration at the field scale. It was found that the higher the rainfall intensity, the lower the amount of rainfall, the longer the time between surface chemical salt and subsequent rainfall, the shallower the leaching depth of surface-applied salt. For wheat research in Kentucky it was found that crop indices monitored in spring time have a closer relationship to crop yield variability than deterministic model-based predictions. Kentucky established a new graduate course PLS 655 in Spatial and Temporal Statistics. New Mexico completed the first phase of the wastewater project and all samples were collected for the second phase. For the Pecan project, most of data collection for years 1 and 2 is completed. Oklahoma will develop a scientifically-sound procedure for interpolating plant available water between Mesonet sites and create and release a new daily plant available water map for drought monitoring in Oklahoma. Oklahoma will also discover the similarities and differences between plant available water and other significant drought indicators. Oregon began a new series of laboratory saline evaporation tests within an environmentally controlled chamber. UC Davis (Harter) secured funding for comprehensive assessment of groundwater nitrate sources, source reduction, groundwater nitrate remediation options, treatment options in drinking water supplies, alternative water supplies in communities currently relying on contaminated groundwater, comprehensive economic analysis, and policy development for the State of California. Research was completed on occurrence, fate, and transport of antibiotics and other pharmaceutical in animal farming facilities. Utah: Characterizations of different electromagnetic sensors as to their dielectric measurement capability and measurement frequency in soils and other reference media has been achieved and publications for both reference media and sensor comparisons are being developed by UA and USU. Wyoming is planning to apply a soil water flow and heat transport model to study the water and energy balance of dryland wheat fields and snow-dominated mountainous forest in southeastern Wyoming. <br /> <br />

Publications

Ahuja., L.R., L. Ma, T.R. Green. 2010. Effective soil properties of heterogeneous areas for modeling infiltration and redistribution. Soil Science Soc. Amer. J. 74(5):1469-1482.<br /> <br /> Andersen, D.S., R.T. Burns, L.B. Moody, M.J. Helmers, and R. Horton. 2010. Comparison of the Iowa State University effluent limitation guidelines model with the soil-plant-air-water model for evaluating containment basin performance. Trans. ASABE 53:207-217.<br /> <br /> Andersen, D.S., R.T. Burns, L.B. Moody, M.J. Helmers, R. Horton, C. Pederson. 2010. The use of the soil-plant-air-water model to predict the hydraulic performance of vegetative treatment areas for controlling open lot runoff. Trans. ASABE 53:537-543.<br /> <br /> Brockhoff, S.R., N.E. Christians, R.J. Killorn, R. Horton, and D. Davis. 2010. Physical and mineral-nutrition properties of sand-based turfgrass root-zones amended with biochar. Agron. J. 102:1627-1631.<br /> <br /> Buckley, M. E., G. J. Kluitenberg, D. W. Sweeney, K. W. Kelley, and L. R. Stone. 2010. Effect of tillage on the hydrology of a claypan soil in Kansas. Soil Sci. Soc. Am. J. 74:2109-2119.<br /> <br /> Das, N.N., B.P. Mohanty, Y. Efendiev. 2010. Characterization of Saturated Hydraulic Conductivity in Agricultural Field Using Karhunen-Loève Expansion with the Markov Chain Monte Carlo Technique. Water Resources Research. 46, 10.1029/2007WR007100.<br /> <br /> Das, N.N., B.P. Mohanty, E.G. Njoku. 2010. Profile Soil Moisture Across Spatial Scales Under Different Hydroclimatic Conditions. Soil Science 175(7):315-319.<br /> <br /> DeSutter, T., E. Viall, I. Rijal, M. Murdoff, A. Guy, X. Pang, S. Koltes, R. Luciano, X. Bai, K. Zitnick, S. Wang, F. Podrebarac, F. Casey, and D. Hopkins. 2010. Integrating Field-Based Research into the Classroom: An Environmental Sampling Exercise. J. Nat. Resour. Life Sci. Educ. 39:132-136.<br /> <br /> Elsadek A., M. Bleiweiss, M.K. Shukla, S. Guldan and S. Fernald. 2010. Alternative climate data sources for distributed hydrologic modeling on a daily time step. Hydrological Processes Journal. DOI: 10.1002/hyp.7917.<br /> <br /> Ewing, R. P., Q. Hu, and C. Liu. 2010. Scale-dependence of intragranular porosity, tortuosity, and diffusivity. Water Resour. Res. 46, doi. 10.1029/2009WR008183.<br /> <br /> Fan, Z., F.X.M. Casey, H. Hakk, G.L. Larsen, and E. Khan. 2010. Sorption, Fate, and Mobility of Sulfonamides in Soils. Water, Air, & Soil Pollution. DOI 10.1007/s11270-010-0623.<br /> <br /> Fang, Q-X., T.R. Green, L. Ma, R. Malone, R.H. Erskine, and L.R. Ahuja. 2010. Optimizing soil hydraulic parameters in RZWQM2 using automated calibration methods. Soil Sci. Soc. Amer. J. 74(6):1897-1913.<br /> <br /> Fang, Q-X., L. Ma, T.R. Green, Q. Yu, Q., T.D. Wang, and L.R. Ahuja. 2010. Water resources and agricultural water use in the North China Plain: Current status and management options. Agric. Water Management 97:1102-1116.<br /> <br /> Fu, W., M. Huang, M. Shao, and R. Horton. 2010. Soil CO2 efflux of two shrubs in response to plant density in the northern Loess Plateau of China. African J. Biotech. 9:6916-6926.<br /> <br /> Fu, X., M. Shao, X. Wei, and R. Horton. 2010. Potential urea-derived nitrogen losses caused by ammonia volatilization and nitrogen leaching in a rainfed semiarid region, China. Acta Agriculturae Scandinavica, Section B - Plant Soil Science 60:560-568.<br /> <br /> Fu, X., M. Shao, X. Wei, and R. Horton. 2010. Soil organic carbon and total nitrogen as affected by vegetation types in Northern Loess Plateau of China. Geoderma 155:31-35.<br /> <br /> Gao, Z., R. Horton, H.P. Liu. 2010. Influence of wave phase difference between surface soil heat flux and soil surface temperature on soil surface energy balance closure. J. Geophys. Res., 115, D16112, doi:10.1029/2009JD013278.<br /> <br /> Green, T.R., Q. Yu, L. Ma, and T.D. Wang. 2010. Crop water use efficiency at multiple scales. Agric. Water Management 97:1099-1101.<br /> <br /> Guan, H., J. Simunek, B. D. Newman, and J. L. Wilson. 2010. Modeling investigation of water partitioning at a semiarid ponderosa pine hillslope, Hydrological Processes, 24(9):1095-1105.<br /> <br /> Gutierrez, I. R., N. Watanabe, T. Harter, B. Glaser, and M. Radke, 2010. Effect of sulfonamide antibiotics on microbial diversity and activity in a Californian Mollic Haploxeralf, J. Soils and Sediments 10(3):537-544, DOI: 10.1007/s11368-009-0168-8.<br /> <br /> Han, X., M. Shao, and R. Horton. 2010. Estimating van Genuchten model parameters of undisturbed soils using an integral method. Pedosphere 20:55-62.<br /> <br /> He, W., H. Liu, Y. Xing, and S.B. Jones. 2010. Comparison of three soil-like substrate production techniques for a bioregenerative life support system. Advances in Space Research 46:1156-1161.<br /> <br /> Heitman, J.L., R. Horton; T.J. Sauer, T. Ren and X. Xiao. 2010. Latent heat in soil heat flux measurements. Agricultural and Forest Meteorology 150:1147-1153.<br /> <br /> Iassonov, P. and M. Tuller, 2010. Application of Image Segmentation for Correction of Intensity Bias in X-Ray CT Images. Vadose Zone J., 9:1-5, doi:10.2136/vzj2009.0042.<br /> <br /> Jia, X., M. Shao, X. Wei, D. She, X. Li, and R. Horton. 2010. Estimating total net primary productivity of managed grasslands by a state-space modeling approach in a small catchment on the Loess Plateau, China. Geoderma, doi:10.1016/j.geoderma. 2010.09.016.<br /> <br /> Jiang, S., L. Pang, G. D. Buchan, J. Simunek, M. J. Noonan, and M. E. Close. 2010. Modeling water flow and bacterial transport in undisturbed lysimeters under irrigations of dairy shed effluent and water using HYDRUS-1D, Water Research, special issue, doi:10.1016/j.watres.2009.08.039, 44:1050-1061.<br /> <br /> Johnson, J., W. Wilhelm, D. Karlen, D. Archer, B. Wienhold, D. Lightle, D. Laird, J. Baker, T. Ochsner, J. Novak, A. Halvorson, F. Arriaga, and N. Barbour. 2010. Nutrient removal as a function of corn stover cutting height and cob harvest. BioEnergy Research 3:342-355.<br /> <br /> Joshi, C. and B.P. Mohanty. 2010. Physical controls of nearsurface soil moisture across varying spatial scales in an agricultural landscape during SMEX02. Water Resources Research., doi:10.1029/2010WR009152.<br /> <br /> Joshi, C., B.P. Mohanty, J. Jacobs, and A.V.M. Ines. 2010. Spatiotemporal analyses of soil moisture from point to footprint scale in two different hydroclimatic regions. Water Resources Research. doi:10.1029/2009WR009002.<br /> <br /> Kamai, T., A. Tuli, G.J. Kluitenberg, and J.W. Hopmans. 2010. Correction to Soil water flux density measurements near 1 cm d-1 using an improved heat pulse probe design. Water Resources Research 46: doi:10.1029/2010WR009423.<br /> <br /> Kandelous, M. M. and J. Simunek. 2010. Numerical simulations of water movement in a subsurface drip irrigation system under field and laboratory conditions using HYDRUS-2D, Agricultural Water Management 97:1070-1076.<br /> <br /> Kandelous, M. M. and J. Simunek. 2010. Comparison of numerical, analytical and empirical models to estimate wetting pattern for surface and subsurface drip irrigation. Irrigation Sci., 28(5), 10.1007/s00271-009-0205-9:435-444.<br /> <br /> Kelleners, T.J. and A.K. Verma. 2010. Measured and modeled dielectric properties of soils at 50 MHz. Soil Sci. Soc. Am. J. 74:744-752.<br /> <br /> Kelleners, T.J., D.G. Chandler, J.P. McNamara, M.M. Gribb, and M.S. Seyfried. 2010. Modeling runoff generation in a small snow-dominated mountainous catchment. Vadose Zone J. 9:517-527.<br /> <br /> Kluitenberg, G. J., T. Kamai, J. A. Vrugt, and J. W. Hopmans. 2010. Effect of probe deflection on dual-probe heat-pulse thermal conductivity measurements. Soil Sci. Soc. Am. J. 74:1537-1540.<br /> <br /> Ko, J., L.R. Ahuja,, B. Kimball, A. Ruane, S.A. Anapalli, L. Ma, T.R. Green, G. Wall, P. Pinter, and D. Bader. 2010. Simulation of free air CO2 enriched wheat growth and interactions with water, nitrogen, and temperature. Agricultural and Forest Meteorology 150:1331-1346.<br /> <br /> Kodeaová, R., J.Simunek, A. Nikodem, and V. Jirko. 2010. Estimation of the dual-permeability model parameters using tension disk infiltrometer and Guelph permeameter, Vadose Zone Journal, Special Section: "Preferential Flow", doi:10.2136/vzj2009.0069, 9(2):213-225.<br /> <br /> Krueger, E.S., T.E. Ochsner, M. Kantar, C. Sheaffer, and P.M. Porter. 2010. Growth stage at harvest of a winter rye cover crop influences soil moisture and nitrogen. Crop Management.<br /> <br /> Laird, D.A, P. Fleming, D.L. Karlen, D.D. Davis, R. Horton, and B. Wang. 2010. Impact of biochar amendments on the quality of a typical midwestern agricultural soil. Geoderma 158:443-449.<br /> <br /> Laird, D.A., P.D. Fleming, B. Wang, R. Horton, and D.L. Karlen. 2010. Biochar impact on nutrient leaching from a midwestern agricultural soil. Geoderma 158:436-442.<br /> <br /> Lee J, Hopmans J.W., Rolston D.E., et al. 2010. Determining soil carbon stock changes: Simple bulk density corrections fail. Agriculture Ecosystems & Environment 138 (3-4):355-355. doi: 10.1016/j.agee.2010.04.016.<br /> <br /> Li, Y., R. Horton, T. Ren and C. Chen. 2010. Prediction of annual reference evapotranspiration using climatic data. Agricultural Water Management 97:300-308.<br /> <br /> Li, Y., R. Horton, T. Ren and C. Chen. 2010. Investigating time scale effects on reference evapotranspiration from Epan data in north China. doi: 10.1175/2009JAMC2130.1. J. Applied Meteorology and Climatology 49:867-878.<br /> <br /> Logsdon, S., T.R. Green, M. Seyfried, and J. Bonta. 2010. Comparison of electrical and thermal conductivities for soils from five states. Soil Sci. 175:573-578.<br /> <br /> Logsdon, S., T.R. Green, M. Seyfried, S.R. Evett, and J. Bonta. 2010. Hydra probe and twelve-wire probe comparisons in fluids and soil cores, Soil Sci. Soc. Amer. J. 74(1):5-12.<br /> <br /> Lü, H., Z. Yu, R. Horton and Y. Zhu. 2010. The retrieval of the root zone soil moisture by the H-infinity filter assimilation procedure. Hydro. Process. 24: 3648-3660.<br /> <br /> Miller, J.O., A.D. Karathanasis, and O.O.B. Wendroth. 2010. In-situ colloid generation and transport in 30 year old mine soil profiles receiving biosolids. Intl. J. Mining, Reclam. Environ. 24:95-108.<br /> <br /> Nippert, J. B., J. J. Butler, Jr., G. J. Kluitenberg, D. O. Whittemore, D. Arnold, S. E. Spal, and J. K. Ward. 2010. Patterns of Tamarix water use during a record drought. Oecologia 162:283-292.<br /> <br /> Pontedeiro, E. M., M. Th. van Genuchten, R. M. Cotta, J. Simunek. 2010. The effects of preferential flow and soil texture on the risk assessments of a NORM waste disposal site, Journal of Hazardous Materials, doi:10.1016/j. jhazmat.2009.09.100, 174(1-3), 648-655.<br /> <br /> Ochsner, T.E., K.A. Albrecht, T.W. Schumacher, J.M. Baker, and R.J. Berkevich. 2010. Water balance and nitrate leaching under corn in kura clover living mulch. Agron. J. 102:1169-1178.<br /> <br /> Sabo, J.L., T. Sinha, L.C. Bowling, G. H. W. Schoups, W.w. Wallender, M.E. Campana, K.A. Cherkauer, P. Fuller, W.L. Graf, J.W. Hopmans, J.S. Kominoski, C. Taylor, S.T. Trimble, R. H. Webb, and E.E. Wohl. 2010. Climate Change and Water in Southwestern North America Special Feature: Reclaiming freshwater sustainability in the Cadillac Desert PNAS. 107(50):21263-21269.<br /> <br /> San Jose Maartinez, F., M.A. Martin, F.J. Caniego, M. Tuller, A. Guber, Y. Pachepsky, and C. Garcia-Gutierrez. 2010. Multifractal analysis of discretized X-ray CT images for the characterization of soil macropore structures. Geoderma, doi:10.1016/j.geoderma.2010.01.004.<br /> <br /> Schaapp, M.G., and M. Tuller, 2010. Quantitative Pore-Scale Investigations of Multiphase Bio/Geo/Chemical Processes. Vadose Zone J., 9:573-575, doi:10.2136/vzj2010.0090.<br /> <br /> Shelver, W.L., H. Hakk, G.L. Larsen, T.M. DeSutter, and F.X.M. Casey. 2010. Development of an ultra-high-pressure liquid chromatography-tandem mass spectrometry multi-residue sulfonamide method and its application to water, manure slurry, and soils from swine rearing facilities. J. Chromatog. A 1217:1273-1282.<br /> <br /> Sartori, F., T. L. Wade, J. L. Sericano, B.P. Mohanty, and K. A. Smith. 2010. Polycyclic Aromatic Hydrocarbons in Soil of the Canadian River Floodplain in Oklahoma. J. Environmental Quality. 39:568-579.<br /> <br /> Sharma P., M.K. Shukla and T. Sammis. 2010. Predicting soil temperature using air temperature and soil and meteorological parameters. Applied Engineering in Agriculture. 26(1):47-58.<br /> <br /> Sowder, J.T., T.J. Kelleners, and K.J. Reddy. 2010. The origin and fate of arsenic in coalbed natural gas produced water ponds. J. Environ. Qual. 39:1604-1615.<br /> <br /> Torkzaban, S., H., N. Kim, J. Simunek, and S. A. Bradford. 2010. Hysteresis of colloid retention and release in saturated porous media during transients in solution chemistry, Environ. Sci. and Technol., 44(5):1662-1669.<br /> <br /> Twarakavi, N. K. C., J. Simunek, and M. G. Schaap. 2010. Can texture-based classification optimally classify soils with respect to soil hydraulics?, Water Resour. Res., 46, W01501, doi:10.1029/2009WR007939.<br /> <br /> Twarakavi, N. K. C., H. Saito, J. Simunek, and M. Th. van Genuchten. 2010. Inverse modeling of vadose zone flow processes using squared e-insensitivity loss function, Journal of Hydrology and Hydromechanics, 58(3):188-200.<br /> <br /> Venterea, R.T., M.S. Dolan, and T.E. Ochsner. 2010. Urea decreases nitrous oxide emissions compared with anhydrous ammonia in a Minnesota corn cropping system. Soil Sci. Soc. Am. J. 74:407-418.<br /> <br /> Wang, L., R. Horton, and Z. Gao. 2010. Comparison of six algorithms to determine the soil apparent thermal diffusivity at a site in the Loess Plateau of China. Soil Science 175:51-60.<br /> <br /> Watanabe, N., B. A. Bergamaschi, K. A. Loftin, M. T. Meyer, and T. Harter, 2010. Use and environmental occurrence of antibiotics in freestall dairy farms with manure forage fields, Environ. Sci. Technol., 2010, 44 (17): 6591-6600, DOI:10.1021/es100834s. (free public access).<br /> <br /> Wei, X., M. D. Hao, X. H. Xue, P. Shi, R. Horton, A. Wang, and Y. F. Zang. 2010. Nitrous oxide emission from highland winter wheat field after long-term fertilization. Biogeosciences, 7: 3301-3310.<br /> <br /> Wei, X., M. Shao, X. Fu, and R. Horton. 2010. Changes in soil organic carbon and total nitrogen after 28 years grassland afforestation: Effects of tree species, slope position and soil order. Plant and Soil 331:165-179.<br /> <br /> Wei, X., M. Shao, J. Zhuang, and R. Horton. 2010. Soil iron fractionation and availability at selected landscape positions in a loessial gully region. Soil Science and Plant Nutrition 56: 617-626.<br /> <br /> Yakirevich, A., T. J. Gish, J.Simunek, M. Th. van Genuchten, Y. A. Pachepsky, T. J. Nicholson, and R. E. Cady. 2010. Potential impact of a seepage face on solute transport to a pumping well, Vadose Zone Journal, 9(3),686-696.<br /> <br /> Books<br /> Radcliffe, D., and J. Simunek. 2010. Introduction to Soil Physics with HYDRUS: Modeling and Applications, CRC Press, Taylor & Francis Group, ISBN-10: 142007380X, ISBN-13: 9781420073805, pp. 373.<br /> <br /> Book Chapters<br /> Hakk, H., F.X.M. Casey, Z. Fan and G.L. Larsen. 2009. A Review of the Fate of Manure-Borne, Land-Applied Hormones. In Keri Henderson and Joel Coats, eds. Veterinary Pharmaceuticals in the Environment. Pg. 11-26. Am. Chem. Soc. Symposium Series 1018. Washington, DC. ISBN: 978-0-8412-6962-0<br /> <br /> Heinse, R. (2011). Space Soil Physics. In: Encyclopedia of Agrophysics (Encyclopedia of Earth Sciences Series), Jan Glinski, Jozef Horabik, Jerzy Lipiec (eds.) Springer.<br /> <br /> Abstacts<br /> Adhikari P., M. K. Shukla, and J. G. Mexal. 2010. Spatial variability of infiltration rate and soil chemical properties of desert soils: Implications for management of irrigation using treated wastewater. New Mexico Water Research Symposium, New Mexico Tech Socorro, NM, August 3, 2010.<br /> <br /> Adhikari P., M. K. Shukla, and J. Mexal. 2010. Spatial variability of soil properties in an arid ecosystem irrigated with treated municipal and industrial wastewater. Soil Science Society of America Annual Meeting held in Long Beach, CA, Oct. 31-Nov 3, 2010.<br /> <br /> Bai, X., F.X.M. Casey, T. DeSutter, H. Hakk, P. Oduor and E. Khan. 2010. Sorption and Degradation of 17²-Estradiol-17 Sulfate in Agricultural Soils. In Annual Meetings Abstracts [CD-ROM]. ASA, CSSA, and SSSA, Madison, WI.<br /> <br /> Carlisle, J., P. Szafruga, V. Mahat, B. Mace, K. Schreuders, S.B. Jones, D.G. Tarboton, L. Hipps and J.L. Boettinger. 2010. Instrumentation Enhancement and Data Processing at the T.W. Daniel Experimental Forest: A Drought Management Initiative Project. Combined Western Snow Conference and Spring Runoff Conference, April 19-22, Logan, UT.<br /> <br /> Casey, F.X.M., and K.G. Richards. 2010. Assessing Persistence and Transport of Manure-Borne Estrogens with Passive Capillary Lysimeters. In Ecotrons & Lysimeters Conference. 29 to 31 March. Palais des Congres, Nancy France.<br /> <br /> Chen-Lopez, J.C., M. Tuller, G.A. Giacomelli, and P. Waller, 2010. Numerical Simulations of Root Zone Fluid Fluxes in Greenhouse Substrates. SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4, 2010.<br /> <br /> Deb S., M.K. Shukla and P. Sharma. 2010. Numerical Analysis of Coupled Liquid Water, Water Vapor, and Heat Transport in a Sandy Loam Soil. 19th World Congress of Soil Science. Brisbane, Australia.1-6 August.<br /> <br /> Deb, S. K., M. K. Shukla, and J. G. Mexal. 2010. Soil moisture depletion patterns for some irrigated pecans. Technical Presentation, the 2010 New Mexico Section ASABE Meeting, April 23, New Mexico State University, Las Cruces, New Mexico.<br /> <br /> Deb S., M. K. Shukla and J. Mexal. 2010. Water fluxes in the unsaturated zone of a mature pecan orchard in arid southern New Mexico. The 2010 New Mexico Water Research Symposium: Resource Interdependence, August 03, 2010, Macey Center, New Mexico Tech, Socorro, New Mexico.<br /> <br /> Deb S. and M. K. Shukla. 2010. Numerical modeling of water vapor fluxes in the unsaturated zone of mature pecan orchards in arid southern New Mexico. The 2010 International Annual Meetings, ASA, CSSA and SSSA, Oct 31-Nov 04, 2010, Long Beach, CA.<br /> <br /> Dontsova, K., E. Hunt, D. L. Gosch, S. Taylor, J. Simunek, J. Chorover, and T. E. Huxman, Dissolution of Unfired and Fired Propellants and Transport of Released Nitroglycerine, 2,4-Dinitrotoluine, and Nitroguanidine in Soils, Abstract H33E-1215 presented at Fall Meeting, AGU San Francisco, 13-17 December 2010.<br /> <br /> Ducas, L., J. Leffler, R. Ryel, and S.B. Jones. 2010. Associations of near-surface soil moisture and annual plant community dynamics. 16th Wildland Shrub Symposium. Utah State University, Eccles Conference Center, May 19.<br /> <br /> Ferre, T.P.A., and M. Tuller, 2010. Monitoring the Seawater Interface with Simple Resistance Measurements. SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4, 2010.<br /> <br /> Gebrenegus, T., T. Ghezzehei, and M. Tuller, 2010. Physicochemical Controls on Initiation and Evolution of Desiccation Cracks in Sand-Bentonite Mixtures: X-Ray Imaging and Stochastic Modeling. SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4, 2010.<br /> <br /> Gonzalez A. and M. K. Shukla. 2010. Transport of Nitrate and Chloride in Saturated Soil Columns. The 2010 New Mexico Water Research Symposium: Resource Interdependence, August 03, 2010, Macey Center, New Mexico Tech, Socorro, New Mexico.<br /> <br /> Gonzalez A. and M. K. Shukla. 2010. Coupled Transport of Nitrate and Chloride in Unsaturated porous Media. 2010 International annual meetings, ASA-CSSA-SSSA, Oct. 31-Nov. 4, 2010, Long Beach, CA.<br /> <br /> Guber, A., M. Tuller, F. San Jose Martinez, P. Iassonov, and M.A. Martin, 2010. The Through Porosity of Soils as the Control of Hydraulic Conductivity. Proceedings of the 19th World Congress of Soil Science, Brisbane, Australia, August 1-6.<br /> <br /> Hanson, B. R., D. M. May, J. W. Hopmans, and J. Simunek, Drip irrigation as a sustainable practice under saline shallow ground water conditions, 19th World Congress of Soil Science, Soil Solutions for a Changing World, 1-6 August 2010, Brisbane, Australia (extended 4 pp abstract), Published on CDROM.<br /> <br /> Heinse, R. and S.B. Jones. 2010. Identifying Thresholds for Water Storage and Transmission In Montane Watersheds From the Soil up. ASA, CSSA, and SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4.<br /> <br /> Hopmans, J. W., P. Hartsough, J. A. Vrugt, J. Simunek, and P. Nasta, Root Water Uptake Modeling, XVIII International Conference on Computational Methods in Water Resources, CMWR 2010, Barcelona, Spain, June 21-24, 2010.<br /> <br /> Jacques, D., J. Simunek, D. Mallants, and M.Th. van Genuchten, Simulating variably-saturated water flow, heat and solute transport and biogeochemistry in porous media using HP1, Geophysical Research Abstracts, 12, EGU2010-4623, EGU General Assembly, Vienna, Austria, May 2-5, 2010.<br /> <br /> Jacques, D., C. Smith, J. Simunek, and D. Smiles, Absorption of artificial piggery effluent by soils: Inverse optimization of hydraulic, solute transport, and cation exchange parameters using HP1 and UCODE, Geophysical Research Abstracts, 12, EGU2010-4639, EGU General Assembly, Vienna, Austria, May 2-5, 2010.<br /> <br /> Jacques, D., J. Simunek, D. Mallants, M. Th. van Genuchten, Reactive transport modelling for variably-saturated flow and contaminant transport problems: Recent HP1 developments, SSSA annual meeting, Long Beach, CA, Nov. 1-4, 2010.<br /> <br /> Jones, S.B., Dani Or, Robert Heinse and Markus Tuller. 2010. Beyond Earth: Designing root zone environments for reduced gravity. 1st International Conference and Exploratory Workshop on Soil Architecture and Physico-Chemical Functions "CESAR". Aarhus University, Research Centre Foulum, Denmark, Nov. 30-Dec. 2.<br /> <br /> Jones, S.B., M. Sakai and G. Kluitenberg. 2010. Exploring Limits of Near-Surface Water Flux Determination from Penta-needle Heat Pulse-Based Measurements. ASA, CSSA, and SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4.<br /> <br /> Jones, S.B., M. Sakai and M. Tuller. 2010. Snowmelt Infiltration and Soil-Water Evaporation Estimates using Heat-Pulse Measurements and Energy Balance Modeling. Combined Western Snow Conference and Spring Runoff Conference, April 19-22, Logan, UT.<br /> <br /> Kamai, T., G. J. Kluitenberg, and J. W. Hopmans. 2010. An alternative heat pulse sensor design. In Annual Meetings Abstracts [CD-ROM]. ASA, CSSA, and SSSA, Madison, WI.<br /> <br /> Kamai, T., A. Ngo, G. J. Kluitenberg, and J. W. Hopmans. 2010. Evaluation of robust heat pulse probes for water content measurement. Abstract H33E-1181. In Abstracts, Fall Meeting, American Geophysical Union, San Francisco, CA [CD-ROM]. December 13-17, 2010.<br /> <br /> Kandelous, M. M., J. Simunek, M. Th. van Genuchten, and K. Malek, Evaluation of soil water content distribution in the subsurface drip irrigation system: field measurement and numerical simulation, SSSA annual meeting, Long Beach, CA, November 1-4, Abstract 300-7 (59877), 2010.<br /> <br /> Kandelous, M. M., T. Kamai, J. A. Vrugt, J.Simunek, B. Hanson, and J. W. Hopmans, An optimization model to design and manage subsurface drip irrigation system for alfalfa, Abstract H53a-0982 presented at Fall Meeting, AGU San Francisco, 13-17 December 2010.<br /> <br /> Kluitenberg, G. J., J. H. Knight, T. Kamai, and J. W. Hopmans. 2010. A semi-analytical solution for the dual-probe heat-pulse method that accounts for the presence of the probes. In Annual Meetings Abstracts [CD-ROM]. ASA, CSSA, and SSSA, Madison, WI.<br /> <br /> Lassabatere, L., D. Yilmaz, R. Angulo-Jaramillo, J. M. S. Ugalde, I. Braud, and J. Simunek, Numerical evaluation of inverse modelling methods for 1D and 3D water infiltration experiments in homogeneous soils, 19th World Congress of Soil Science, Soil Solutions for a Changing World, 1-6 August 2010, Brisbane, Australia (extended 4 pp abstract), Published on CDROM.<br /> <br /> Lazarovitch, N., L. Krounbi, and J. Simunek, Models for root water uptake under deficit irrigation, Geophysical Research Abstracts, 12, EGU2010-6272, EGU General Assembly, Vienna, Austria, May 2-5, 2010.<br /> <br /> Morari F., I. Coletto, M. Drigo, M. L. Menandro, J. Simunek, and M. Martini, Transport and deposition of Escherichia coli O157:H7 and Enterococcus faecalis in three Italian soils, 19th World Congress of Soil Science, Soil Solutions for a Changing World, 1-6 August 2010, Brisbane, Australia (extended 4 pp abstract), Published on CDROM.<br /> <br /> Neumann, L. E., J. Simunek, F. J. Cook, and D. Jacques, Implementation of quadratic upstream interpolation schemes and monotonic maintenance for evaluating reactive solute transport in HYDRUS-1D and HP1, SSSA annual meeting, Long Beach, CA, November 1-4, Abstract 302-1 (59275), 2010.<br /> <br /> Peyrard, S., L. Lassabatere, R. Angulo-Jaramillo, and J.Simunek, An analytical model for cumulative infiltration into a dual-permeability media, Geophysical Research Abstracts, 12, EGU2010-7787, EGU General Assembly, Vienna, Austria, May 2-5, 2010.<br /> <br /> Ramos, T. B., J. Simunek, M. C. Gonçalves, J. C. Martins, A. Prazeres, N. L. Castanheira, and L. S. Pereira, Field evaluation of a multicomponent solute transport model in soils irrigated with saline waters, SSSA annual meeting, Long Beach, CA, November 1-4, Abstract 297-5, 2010.<br /> <br /> Resurreccion, A.C., P. Moldrup, M. Tuller, T.P.A. Ferre, K. Kawamoto, and T. Komatsu, and L.W. De Jonge, 2010. Soil Water Retention at Dry Conditions and its Relation to Specific Surface Area and Texture. Proceedings of the 1st International Conference and Exploratory Workshop on Soil Architecture and Physico-Chemical Functions (CESAR), Research Centre Foulum, Denmark, Nov 30-Dec 2.<br /> <br /> Resurreccion, A., P. Moldrup, P. Schjonning, M. Tuller, T.P.A. Ferre, K. Kawamoto, T. Komatsu, and L.W. De Jonge, 2010. The Soil Characteristic Curve at Low Water Contents: Relations to Specific Surface Area and Texture. SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4, 2010.<br /> <br /> Robinson, D.A., S.B., Jones, S.P. Friedman and T.E. Doyle. Modeling Structural Effects on the Determination of Soil Moisture using Microwave Measurements in Granular Porous Media. GPR 2010 Workshop. Rome, Italy.<br /> <br /> Sakai M., S.B. Jones and M. Tuller. 2010. Estimation of Evaporation Rates from a Subsurface Drying Front using a Penta-Needle Heat Pulse Probe. ASA, CSSA, and SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4.<br /> <br /> Sakai, M., and S.B. Jones. 2010. Numerical Evaluation of Snowmelt Infiltration Using Soil Water Content Monitoring. Combined Western Snow Conference and Spring Runoff Conference, April 19-22, Logan, UT.<br /> <br /> Sharma, P., M. K. Shukla, and J. Mexal. 2010. Spatial variability of soil hydraulic properties in agricultural fields of Southern New Mexico: Implication on irrigation management. New Mexico Water Research Symposium held in New Mexico Tech Campus, Scorro, NM, August 3, 2010.<br /> <br /> Sharma, P., M. K. Shukla, J. Mexal, and T. W. Sammis. 2010. Spatial variability of soil properties in agricultural fields of Southern New Mexico. 2010 Int. annual meetings, ASA-CSSA-SSSA, Oct. 31-Nov. 4, 2010, Long Beach, CA.<br /> <br /> Simunek, J., J. W. Hopmans, and N. Lazarovitch, A new compensated root water and nutrient uptake model implemented in HYDRUS programs, Geophysical Research Abstracts, 12, EGU2010-3640, EGU General Assembly, Vienna, Austria, May 2-5, 2010.<br /> <br /> Smith, C., D. Jacques, J. Simunek, and D. Smiles, Absorption of artificial piggery effluent by soils: Inverse optimization of hydraulic, solute transport, and cation exchange parameters using HP1 and UCODE, SSSA annual meeting, Long Beach, CA, November 1-4, Abstract 297-10 (59986), 2010.<br /> <br /> Steenpass, C., J. Vanderborght, M. Herbst, J. Simunek, and H. Vereecken, Using IR-measured soil surface temperatures to estimate hydraulic properties of the top soil layer, Geophysical Research Abstracts, 12, EGU2010-15021, EGU General Assembly, Vienna, Austria, May 2-5, 2010.<br /> <br /> Sun, H., K. Kopp and S.B. Jones. 2010. Simulation of Water and Nutrient Transport in Three Turf Species. ASA, CSSA, and SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4.<br /> <br /> Sun, H., K. Kopp, M. Dietz, S.B. Jones and J. Fan. 2010. A Comprehensive Research Method to Investigate the Environmental Issues of Urban Landscapes: Water Use and Nitrogen Leaching of Urban Landscapes on Community Water Quantity and Quality. American Society for Horticultural Science Annual Meeting. Palm Desert, CA, 2-5 August 2010.<br /> <br /> Tuller, M., C.M.P. Vaz, and R. Kulkarni, 2010. A New Generation of High-Resolution Benchtop Micro-CT Scanners for Application in Soil Science. Proceedings of the 1st International Conference and Exploratory Workshop on Soil Architecture and Physico-Chemical Functions (CESAR), Research Centre Foulum, Denmark, Nov 30-Dec 2.<br /> <br /> Tuller, M., C.M.P. Vaz, P.R.O. Lasso, R. Kulkarni, and T.P.A. Ferre, 2010. Evaluation of a High-Resolution Benchtop Micro-CT Scanner for Application in Porous Media Research. Eos Trans. AGU, Fall Meet. Suppl., Abstract H13D-1013. <br /> <br /> Tuller, M., T.P.A. Ferre, and M.S. Mirjat, 2010. Optimization of Border Irrigation for Salinity Control in Arid and Semiarid Regions. SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4, 2010.<br /> <br /> Twarakavi, N. K., and J. Simunek, A coupled modeling approach to incorporate vadose- zone flow and solute transport in ground water models, Geophysical Research Abstracts, 12, EGU2010-7646, EGU General Assembly, Vienna, Austria, May 2-5, 2010.<br /> <br /> Twarakavi, N. K., J. Simunek, and L. Bahaminyakamwe, A coupled modeling approach to incorporate vadose-zone flow and solute transport in ground water models, SSSA annual meeting, Long Beach, CA, November 1-4, Abstract 297-13, 2010.<br /> <br /> van Genuchten, M. Th., D. Jacques, J. Simunek, and D. Mallants, Models for Predicting Radionuclide Transport in Soils and Groundwater, Keynote presentation, ENCIT 2010,13th Brazilian Congress of Thermal Sciences and Engineering, Dec. 5-10, 2010, Uberlandia, MG, Brazil.<br /> <br /> Vaz, C.M.P., J.M. Manieri, I.C. De Maria, and M. Tuller, 2010. Modeling the Influence of Water Content and Bulk Density on Soil Penetration Resistance. SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4, 2010.<br /> <br /> Vaz, C.M.P., P.R.O. Lasso, and M. Tuller, 2010. Quantification of Phase Distributions in Porous Media with High-Resolution Benchtop Micro-CT. SSSA International Annual Meeting, Long Beach, CA, Oct. 31-Nov. 4, 2010.<br /> <br /> Vrugt, J. A., J. Hopmans, P. Hartsough, J. Simunek, and P. Nasta, Bayesian Calibration of a Soil-Root-Plant-Atmosphere Continuum Model Using Soil Moisture and Leaf Water Potential Data, Geophysical Research Abstracts, 12, EGU2010-12148, EGU General Assembly, Vienna, Austria, May 2-5, 2010.<br /> <br /> Wendroth, O., V. Vasquez, and C. J. Matocha. 2010. Spatial Variation Scales of Rainfall Characteristics and Bromide Leaching. Poster. American Geophysical Union, Fall 2010, Dec. 13-18, San Francisco.<br /> <br /> Wendroth, O. 2010. Combined space-time state space model for field soil water storage. Oral Presentation. Annual Meeting, ASA-CSSA-SSSA, Oct. 30-Nov. 4, 2010, Long Beach, CA.<br /> <br /> Wendroth, O., C.J. Matocha, and V. Vasquez. 2010. Field-Scale Bromide Transport as a Function of Rainfall Amount, Intensity and Application Time Delay. Poster. 19th World Congress of Soil Science, IUSS, Brisbane, Australia, Aug. 01-06, 2010.<br /> <br /> Wendroth, O., V. Vasquez, and C.J. Matocha. 2010. Impact of rainfall amount, intensity, and time lag on leaching behavior of a surface-applied Bromide tracer. Oral Presentation. Kentucky Water Resources Annual Symposium, March 22, 2010, Griffin Gate Marriott Resort, Lexington, KY.

Impact Statements

1. New tools, devices -- New 11-needle heat pulse sensors provide accurate measurements of soil water evaporation which supports urban and rural water use planning. (IA) A rapid multi-residue method for the determination of commonly used antibacterial sulfonamides was developed. (ND)
2. New scientific knowledge -- Rainfall forecasting before applying fertilizers or pesticides improves stewardship of soil and water resources. (KY) Study of the hydrologic processes at the groundwater-agriculture interface in animal ag facilities aided the design of efficient regulatory programs. (CA)
3. Improve measurement techniques -- Physical location of high and low sodicity and hydraulic conductivities improved irrigation scheduling of wastewater for Pecans. (NM) Work on claypan soils showed that conventional tillage had greater evaporation and less runoff than conservation tillage early in the season. (KS)
4. Develop stronger connections -- A daily plant available water map for drought monitoring that is under development will allow farmers to change forward contracting strategies and project livestock forage needs. (OK) Near-real time output for forest ecosystems is available with access to climate data. (UT)
5. Improve protection -- Measurement and modeling methodologies were developed to characterize hydrology of the vadose zone across spatial scales through alternative soil water sensors. (CA) HYDRUS shortcourses were conducted at international locations and upgrades were implemented. (CA)

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Report Information

Participants

Berli, Markus, markus.berli@dri.edu, Desert Research Inst., Las Vegas, NV; Bradford, Scott, scott.bradford@ars.usda.gov, USDA Salinity Lab., Riverside, CA; Caldwell, Todd, todd.caldwell@dri.edu, Desert Research Inst., Reno, NV; Casey, Frank, francis.casey@ndsu.edu, North Dakota State Univ., Fargo, ND; Chief, Karletta, karletta.chief@dri.edu, Desert Research Inst., Las Vegas, NV; Evett, Steve, steve.evett@ars.usda.gov, Bushland, TX; Ewing, Toby, ewing@iastate.edu, Iowa State Univ., Ames, IA; Flury, Markus, flury@wsu.edu, Washington State University, Pullman, WA; Heinse, Robert, rheinse@uidaho.edu, Univ. of Idaho, Moscow, ID; Horton, Bob, rhorton@iastate.edu, Iowa State Univ., Ames, IA; Jones, Scott, scott.jones@usu.edu, Utah State Univ., Logan, UT; Kelleners, Thijs, tkellene@uwyo.edu, Univ. of Wyoming, Laramie, WY; Miller, Watkins, wilymalr@unr.edu, Univ. of Nevada, Reno, NV; Mohanty, Binayak, bmohanty@tamu.edu, Texas A&M Univ., College Station, TX; Nieber, John, nieber@umn.edu, Univ. of Minnesota, St. Paul; Ochsner, Tyson, tyson.ochsner@okstate.edu, Oklahoma State Univ., Stillwater, OK; Schwartz, Robert, robert.schwartz@ars.usda.gov, USDA-ARS, Bushland, TX; Simunek, Jirka, jiri.simunek@ucr.edu, Univ. of California, Riverside, CA; Skaggs, Todd, todd.skaggs@ars.usda.gov, USDA Salinity Lab., Riverside, CA; Tuller, Markus, mtuller@cals.arizona.edu, Univ. of Arizona, Tucson, AZ; Twarakavi, Navin, navin.twarakavi@dri.edu, Desert Research Institute, Las Vegas, NV; Tyler, Scott, styler@unr.edu, University of Nevada, Reno, NV; Wendroth, Ole, owendroth@uky.edu, Univ. of Kentucky, Lexington, KY; Young, Michael, michael.young@beg.utexas.edu, Univ. of Texas, Austin, TX; Zhu, Julian, jianting.zhu@dri.edu, Desert Research Inst., Las Vegas, NV

Brief Summary of Minutes

Accomplishments

Short-term Outcomes: W-2188 participants mentored >20 MS students, PhD students, and Post-doctoral researchers this year. Participants in Arizona developed a new fully-automated (no operator bias) algorithm for multiphase segmentation of X-ray computed tomography data of porous media with potential for real-time segmentation and applicability in biomedical research. Participants in California developed a mathematical model for pathogen transport and retention that accounts for observed trends in pathogen and soil size, velocity, chemical interactions, and concentration. Participants in Idaho continued work on characterizing preferential flow pathways in forested hill slopes. Tree stumps left behind after logging are a common feature of managed forests. Subsequent forest fires often result in the complete combustion of decayed stumps and roots, leaving behind empty soil pipes. These soil pipes potentially provide rapid subsurface lateral flow pathways for water that play a critical role in hill slope hydrology and stability. Electrical resistivity (ERT) was used as a non-invasive technique to produce a three dimensional representation of the soil subsurface. Pre-burn ERT images indicated a portion of an existing soil pipe. A post burn survey of soil pipe openings over the 2 hectares documented 198 surface soil pipe openings. Most soil pipe openings exhibited evidence of forming from, or being enhanced by, the combustion of decaying tree roots. Comparing pre- and post-burn ERT images demonstrated the degree of soil pipe formation due to the prescribed burn. A better understanding of soil pipe distribution is crucial for water management in forested ecosystems. Participants in Iowa developed and tested an improved formulation of scale-dependent diffusion coefficients. Participants in Kentucky discovered additive state-space models are a promising approach to separate large-scale soil spatial variation from small-scale variation imposed by rainfall treatment in field-scale solute transport experiments. With increasing rainfall intensity, the solute leaching increases for the same amount of rainfall. The larger the time between solute application and subsequent rainfall, the smaller the probability of deep leaching and ground water contamination. Additive state-space models through their ability to separate large- from small-scale variation support appropriate nitrogen management while the assumption of one unique Yield-N-response function becomes unnecessary. In farmers fields, with current technology, nitrogen application rate in wheat can be managed at a scale of 4 by 5 m2 or larger based on crop sensors and derived vegetative indices, e.g., NDVI. It is not reasonable yet to manage at a smaller scale. Participants in Minnesota analyzed stream flow data with factor analysis and identified artificial drainage and land cover change as possible causes of increased stream flow in Minnesota. This result will be tested further using alternate methods of analysis. Channel widening of the Minnesota River is evidence for one of the sources of increased sediment in the river. Evaluation of the deposition of this sediment as well sediment derived from other sources such as fields, bluffs and ravines onto point bars and onto flood plain areas is ongoing to provide for estimates of the sediment budget. Participants in Nevada derived guidelines of effective soil hydraulic parameters to predict average infiltration and subsequent moisture redistribution over a large scale heterogeneous field. They also developed an approach to investigate how the harmonic mean function of hydraulic conductivities of individual soil layers would perform in predicting evaporation and infiltration fluxes in a layered heterogeneous profile. They also showed that soil-root interfaces can be imaged using CMT and changes in macro-pore volume of the rhizosphere can be quantified employing numerical image analysis and Finite Element simulations. A new method to estimate Green-Ampt infiltration parameters was developed based on soil moisture measurements and cumulative infiltration curves obtained during rainfall simulator tests. This parameter optimization procedure optimized results for the hydraulic conductivity and potential at the wetting front. The approach worked well for ideal, measured infiltration curves. Laboratory studies in North Dakota indicate that estradiol associates with colloids derived from manures, which implies that they can be transport on and through soils. Additionally, we demonstrated that estradiol can be dislodged from colloids. The implication of this result is if estradiol is transport by a colloid to end-point source of water, it can dissociate from the colloid, becoming available to negatively impact biological organisms. The laboratory experiments with the conjugate derived estradiol indicated that sulfate conjugates can transform into the potent estradiol molecule in soil solutions. The implication of these results from the conjugate studies is that conjugates, which are prevalent in animal manures, can contribute potent estradiol into the environment. A glucuronide conjugate of estradiol was detected in a field well water sample several meters below the land surface, which supports our conclusions that conjugates can enhance the mobility of estradiol through the soil. Composting had little effect on the total estrogenic activities in swine manures compared to non-composted manures. It was found that the most potent estrogen, estradiol, had already converted to estrone at the start of the experiment. These composting results indicate that estrogenic activities, and associate toxicities, are at a reduced level before composting is commenced. Soils amended with CGR significantly increased the pH of the soil, increased the soil EC, and had no effect on the soil trace metal concentrations. These results indicate that CGR could be used as a soil liming agent to increase the soil pH, thus increasing the nutrient availability in the soil. The plant shoot biomass was affected by the CGR. In Oklahoma key outcomes of this project were advances in scientific knowledge on methods to monitor soil water content and plant available water. This new knowledge was generated by the project team and shared with an international audience of researchers through a presentation at the ASA-CSSA-SSSA Annual Meeting in San Antonio, TX. A second outcome was an enhancement of the conditions for further research. The project results laid the foundation for two new research grants this year; one from the Oklahoma Water Resources Research Institute, and one from the Joint Fire Science Program. Both of these grants focus on soil water dynamics. Participants in Texas improved understanding and predictability of soil water and chemical transport processes at different scales. Users of soil water sensors were educated on their usefulness for different objectives through published papers and chapters, and presentations at conferences. Participants in Washington continued work on identifying fundamental mechanisms controlling colloid transport in unsaturated porous media. Direct applications of this work is done at the Hanford Nuclear Reservation, where the work helps to identify hazards of groundwater contamination and guides clean-up strategies and long-term remediation and management of the site. The Water Erosion Prediction Project (WEPP) model was further developed and tested. In collaboration with the USDA NSERL, the online WEPP GIS interface, a user friendly interface to assist in watershed hydrologic and erosion assessment, was developed. The model performance was tested by applying it to two selected forest watersheds in the Great Lakes Basin. A field study was also conducted to evaluate the impacts of residue management on snow distribution and soil water storage. In Wyoming automated monitoring of soil-state variables such as water content, temperature, and CO2 concentration continued as part of several multi-investigator research projects in irrigated fields, rangeland soils, and forest ecosystems. Development of a numerical soil water flow, heat transport, and CO2 transport computer code continued, with improvements being made in the calculation of leaf stomatal conductance, snow albedo, and output visualization. <br /> <br /> Outputs: W-2188 participants authored 97 peer-reviewed papers, 12 book chapters, 100 abstracts and proceedings papers, 4 technical reports, and 2 patent applications in 2011. Participants in California engaged in collaborative research with engineers in Brazil, atmospheric scientists in Israel, and agronomists in Pakistan. HYDRUS models have been updated with several new capabilities and options that have been developed for various research projects. These included: a) irrigation and fertigation scheduling (triggered irrigation), b) overland flow module, c) transport of stable water isotopes. Participants in Idaho collaborated with Utah State University (Scott Jones) and the University of Arizona (Markus Tuller) on space soil physics and mine tailing re-cultivation. In addition, collaboration was been established with NMT (White) and UNR (Saito) on the development of novel approaches to identify triggers of drastic environmental change. Participants in Iowa measured breakthrough curves in structured and unstructured soils to investigate the effect the presence of suspended colloidal material has on estradiol (E2) transport in soil. Initial results indicate that colloids can be rapidly transported and carry E2 with them when preferential flow channels are present. Swine manure derived colloids appear to be less mobile than soil derived colloids (likely due to size exclusion enhancing the larger soil colloids movement), but both have been eluted with E2 attached to them. E2 and its daughter product estrone were both eluted in the solution phase (estrone peaking later than E2) and both lagged behind a rapid arrival of bromide. Biochar amendments enhanced water retention in sandy loam and silt loam soils. The effect of biochar on water retention was pronounced in coarse-textured soils. Bulk density of sandy loam and silt loam soils decreased from 1.41 g/cm3 to 1.15 g/cm3 and 1.23 g/cm3 to 0.95 g/cm3, respectively, as the rates of biochar increased from 0 to 6 %. Soil carbon dioxide (CO2) fluxes in the soil profile were determined with a gradient method by measuring CO2 concentration and estimating gas diffusion coefficient with depth and time. CO2 sensor measurement provided realistic CO2 distribution and movement in the soil profile. CO2 concentration increased with the increase of soil depths and CO2 concentration increased immediately after rainfall events at all the soil depths. Soil carbon dioxide (CO2) fluxes obtained from gradient method showed the values of CO2 fluxes and the diurnal variation decreased with the increase of soil depths and the CO2 flux was stable below 100 mm soil depth. The values of soil surface CO2 efflux from the gradient method were similar to the closed-chamber values. Eddy covariance CO2 flux agreed well with the other methods during night periods but not during day periods when wind speed and solar radiation were relatively large. Results from this study indicated that soil CO2 fluxes can be estimated from soil CO2 sensors. Although evapotranspiration (ET) is a main component of the hydrological cycle, accurate partitioning of ET into evaporation (E) and transpiration (T) is challenging. Evaporation was measured using heat pulse sensors, transpiration T using stem flow gauges, and ET using an eddy covariance system in a corn field. Potential evapotranspiration, ET0, was also calculated with the Priestley-Taylor equation for a 12 day measurement period. Potential ET0 was larger than the individually measured E+T and eddy covariance ET. Eddy covariance ET was consistently lower than the individually measured E+T and the potential ET0 during the measurement period. E, T, E+T and eddy covariance ET accounted for 8%, 77%, 85% and 61% of potential ET0, respectively, during the 12-day period. Participants in Minnesota have conducted work to evaluate the causes of the increased stream flow which has been linked to increased sediment loads in the Minnesota River using a variety methods, including hydrograph analysis, isotope flow separation methods, and water balance modeling. Of interest to stakeholder groups is the prioritization of the sites that have the greatest potential benefits for sediment reduction. Results are being used interactively with the stakeholder groups to develop the prioritizations. The assessment of near-channel source erosion has been conducted without examining the detailed processes involved in the erosion. More work needs to be done on this to be able to promote better understanding of how the erosion occurs and to design mitigation schemes. It is assumed that the erosion of the near-channel sources of sediment is not only the result of boundary shear, but also the result of subsurface flow processes (sapping, piping, etc.). Work has been initiated to develop models of these processes and to work collaboratively with researchers (e.g., USDA Sedimentation Lab, Oxford, MS) who are developing laboratory and field data for model testing. Soil freezing is an important process over large parts of Earth. The process affects surface hydrology (due to effects on rainfall-runoff partitioning), land surface-atmosphere energy balances, soil erosion, soil genesis, solute transport, and human infrastructure. Models of soil freezing processes are needed to be able to quantify these effects, and while many models do exist, most have significant limitations when it comes to prediction of the highly nonlinear behavior of soil freezing. Models are being developed for soil freezing that eliminates some of the limitations of previous models. In North Dakota laboratory experiments were conducted to identify whether soil and/or manure derived colloids and dissolved organic carbon (DOC) can facilitate the transport and increase the persistence of estradiol. Colloids and DOC were separated from field soils and swine manure and were mixed in solutions with radiolabelled (14C) estradiol. The partitioning of the estradiol to the colloids and DOC were observed. Additionally, soil batch laboratory experiments were conducted using radiolabelled estradiol conjugates of sulfate to identify the partitioning of the sulfate conjugate and its metabolites to soils. The sulfate conjugates and its metabolites were modeled. Compost was investigated as a means to ameliorate the estrogenic levels in swine manures. The chemical composition and characteristics of concrete grinding residues (CGR), a waste product road construction, were determined along with its effect on the mechanical properties of soil, and whether it has an effect plant growth. In Oklahoma the soil water retention characteristics necessary to facilitate monitoring of plant available water via the Oklahoma Mesonet were measured. The laboratory measurements of these key soil properties were completed for every Mesonet site. The accuracy of this new plant available water monitoring capability was also validated by direct measurement with soil sampling. In Texas participants conducted several field campaigns to better understand the underlying processes controlling the spatio-temporal variations of soil moisture using multiple ground, air, and space-borne sensors. Spatio-temporal variabilitys, time stability, as well as their geophysical controls at different measurement support scales (point-scale, airborne, to space borne remote sensor footprints) were studied in different hydro-climatic regions. Results showed that soil properties (i.e., percentage silt, percentage sand, and soil texture), and topography (elevation and slope) are significant physical controls jointly affecting the spatio-temporal evolution and time stability of soil moisture at both point- and footprint-scale. In addition, new up scaling methods were developed for soil hydraulic properties at the hill slope scale based on topographic features. Controlled soil column experiments, mimicking various environmental boundary conditions and geological heterogeneities were used to investigate water flow and contaminant transport in macroporous, fractured, layered, and lensed soil columns. Results were analyzed using forward and inverse modeling including Markov Chain Monte Carlo (MCMC) algorithm to define complex processes and parameter uncertainties. In Utah work at the TW Daniel Experimental Forest site continued with data analysis to extract evaporation and transpiration estimates for vegetation species being studied there. The site was updated with two new instruments during late summer of 2011 to monitor soil moisture and snow water equivalent. Ongoing work with the Penta-needle Heat Pulse Probe (PHPP) has become a very productive effort with multiple applications being developed in the past year. The probe has been described regarding its potential to estimate subsurface soil evaporation as well as providing soil heat flux estimates. In addition, the PHPP can be used to monitor soil water flux, providing both magnitude and direction between 1 and 10,000 cm/d. A number of presentations were delivered at national meetings describing these applications. Electromagnetic sensor comparison work was conducted at the University of Arizona with Carlos Vaz and Markus Tuller, from which two presentations at meetings were delivered based on that work. Participation at the SOIL FUTURE workshop in Denmark resulted in acceptance of a manuscript in VZJ. Collaboration with Colleagues in Israel resulted in funding of a BARD Proposal aimed at developing measurement capabilities to monitor soil water and nutrient movement. Participants in Washington identified a unique aspect of colloid mobilization in unsaturated porous media, namely the different effects of advancing and receding air-water interfaces on colloid scouring from solid-water interfaces. An experimental system to study colloid transport in porous media in a geocentrifuge was developed. A predictive system to simulate seed-zone water contents in the dryland wheat-cropping system of Washington State was developed. A new user interface for the WEPP model was developed and tested. This new interface uses the OpenLayers and MapServer GIS software with base image data from Google. Custom programs in C++ assist in both preparation of WEPP inputs and interpretation of WEPP outputs. A user needs only a web browser to set up and perform WEPP simulations, with geospatial (DEM, soil, land use) and climatic data all auto-retrieved and processed. Participants in Wyoming published a study in SSSAJ on the determination of depth-wise water retention in seasonally frozen field soils using Hydra impedance sensors. Unfrozen soil water content was derived from the real permittivity using a dielectric mixing model while soil water pressure head was calculated from freezing soil temperatures using the Clapeyron equation. Comparison of the Hydra water retention data with laboratory retention data showed mixed results. The best results were obtained for the shallowest sensors because of the more significant and more prolonged soil freezing at these depths, resulting in relatively wide ranges for the calculated soil water pressure heads. Fitted curves for the Hydra sensor water retention data yielded unreliable parameters because of insufficient information on the wet end of the water retention curves. Two papers on CO2 production and transport in a rangeland soil were submitted to SSSAJ and VZJ, respectively. The SSSAJ paper used the gradient method to calculate depth-wise CO2 flux and production. Temperature-normalized CO2 production was found to be a function of soil water content, with maximum production being observed at 0.165- 0.225 m3 m-3. The VZJ paper used a numerical model to calculate the water, heat, and CO2 fluxes in the soil-plant-atmosphere system. Calculated ecosystem respiration was 176-178 g C m-2 yr-1 over two years. The relatively low respiration values were expected, given the relatively high elevation of the study site (2200 m above sea level), resulting in a short growing season.<br /> <br /> Activities: Arizona: A major project was begun on the development of a physically-based predictive model for soil evaporation that considers the thermal footprint measured with a highly sensitive thermal camera, water fluxes measured with an array of Penta Needle Heat Pulse Probes (PNHPP), and physical soil properties such as thermal and hydraulic conductivities and texture. Another major project was initiated aimed at the development of economically feasible gradient-based and surface chamber techniques for measurement of greenhouse and regulated gas emissions from animal feeding operations. To develop strategies for optimizing hydrological conditions in mine tailings in the arid Southwest, electromagnetic induction (EMI) surface surveys were applied to characterize spatial heterogeneity of physical and mineralogical tailings properties.<br /> California: Progress was made in modeling the effects of soil moisture status on pesticide volatilization. Extensive salt accumulation and leaching data collected over four years were analyzed and compared with model predictions. Researchers at Riverside, California used techniques from theoretical physics to develop a new model explaining permeability in terms of pore-structure and demonstrated that the model was more accurate than previous models. Research was initiated to examine pathogen transport in runoff water. In particular, we have designed and built an overland flow chamber (3 m long, 15 cm high and 18 cm wide) to study pathogen transport with runoff water. Preliminary conservative tracer (bromide) and E. coli O157:H7 transport studies were conducted in this chamber to develop and refine experimental protocols and to examine the influence of solution chemistry on the transport and release of E. coli O157:H7 in runoff water. A model to simulate water flow and pathogen transport in overland flow and in variably saturated soils under a wide range of conditions was developed using the COMSOL software package. Numerical experiments are being conducted to examine: (1) the influence of the surface mixing zone, spatial variations in surface topography, and depression storage on pathogen removal; (2) the dynamic interactions of surface and subsurface water flow on pathogen transport; (3) the influence of pathogen size; and (4) and the role of pathogen retention parameters. The dual permeability pathogen transport model was coupled to solution ionic strength (IS). In particular, the relevant retention model parameters (sticking efficiency, maximum retention capacity, and release rate) were continuously updated at each time step to reflect differences in solution IS. This model was used to simulate previously measured colloid and microorganism (E. coli D21 g and coliphage ÆX174) release behavior with transients in IS. Laboratory and numerical studies were conducted to investigate the influence of physical and chemical factors on the transport of E.coli O157:H7 and coliphage ÆX174 through preferential flow systems. Preferential flow systems were created in 13.2 cm diameter and 20 cm length columns by embedding sand lens of various grain size, length, and vertical position into finer textured matrix sand. Tracer solutions containing bromide and microbes were prepared at different ionic strength (IS) and sprayed onto the surface of the columns at desired steady rates using a rain simulator to achieve saturated or unsaturated conditions. Effluents were collected at the column bottom continuously and analyzed for concentrations of bromide, ÆX174, and E.coli. Complementary numerical simulations were conducted using the HYDRUS 2D code over a wider range of physical and chemical conditions, and to analyze bromide and microbe transport in the columns. Short (two to five days) courses were offered on how to use HYDRUS models at a) University of Calgary, Alberta, b) Czech University of Life Sciences, Prague, Czech Republic, c) Colorado School of Mines, Golden, CO, and d) International Atomic Energy Agency (IAEA), Vienna, Austria. Over 60 students participated in these short courses.<br /> Idaho: Organized and hosted the Innovative Working Group meeting on 'Identifying complementary indicators of ecological thresholds in a changing climate.' The IWG was held from February 2--5, 2011 at the McCall Outdoor Science School in Central Idaho. The IWG brought together a cross-disciplinary group of scientist to develop the idea of identifying complementary indicators of ecological thresholds in a changing climate. Outcomes of the IWG include responding to calls for proposals by the USDA, as well as furthering collaboration via the proposal of two targeted topical sessions at the 2011 AGU meeting and the development of a future synthesis paper and possibly a book publication. Chaired and organized a session on 'Detecting Thresholds of Ecosystem Resilience in a Changing Climate' with co-chairs Caiti Steele and Amanda White at the 2010 Fall Meeting of AGU. Chaired and organized a session on 'Water Resources: State and Change' with co-chairs with co-chair John Meija at the Tri-State Western Consortium Meeting.<br /> Iowa: New understanding of percolation-based scale-dependent properties of soil and rock was incorporated into a finite difference model of diffusion with nonlinear sorption, for use in predicting movement of groundwater pollutants. The program was used to analyze a published dataset, and it gave an improved understanding of the dynamics.<br /> Kentucky: A field-scale solute leaching experiment was conducted to improve understanding of the impact of land use, rainfall amount, intensity and application time delay on the leaching of bromide. A remote-sensing based experiment was conducted in a farmers field in Western-KY to test the improvement of N-fertilization through the use of the GreenSeeker and derived NDVI of winter wheat. An additive state-space statistical model was adapted for the analysis of agricultural experiments. Treatments can efficiently apply non-randomly but varying periodically at different scales so that underlying soil heterogeneity effects can be compensated in the analysis. A graduate level course in soil physics (with lab) was taught.<br /> Minnesota: Development of maps of regional groundwater recharge at multiple mapping scales. Assessment of the influence of land use and land cover change on the water balance of watersheds in Minnesota. Assessments of the quantity of near-channel erosion in selected watersheds in various regions of Minnesota. Modeling the process of subsurface flow on the erosion of stream banks, bluffs, and hillslopes. Development of models of freezing processes in soils. <br /> Oklahoma: Completed laboratory measurements of soil physical properties at all Oklahoma Mesonet stations. Managed and expanded the Marena Oklahoma In Situ Sensor Testbed (MOISST) in support of NASAs upcoming Soil Moisture Active/Passive (SMAP) satellite mission. <br /> Texas: Completed the second year of a study that involves detailed seasonal monitoring of soil water content within the root zone of deficit irrigated and fully irrigated sorghum. Evaluated the accuracy of TDR microlysimeters in providing daily and sub-daily estimates of soil water evaporation in this cropped field. Completed a four-year study comparing the hydrologic response of a cropped field to tillage or no tillage at two locations (Bushland, TX and Tribune, KS) and analysis of the extensive data set is continuing. Completed a study involving the use of column displacement experiments to evaluate the sensitivity of permittivity measurements to bulk electrical conductivity independent of soil water content for three sensors (5TE, Acclima, and TDR). Completed a multi-sensor field comparison of local soil water content and bulk electrical conductivity sensors. It involved six sensors each of the Decagon 5TE, Stephens Hydra Probe, Acclima ACC-TDT, and Campbell Scientific CS655 (an earlier field comparison employed the CS616). Sensor outputs in terms of permittivity (real or apparent), water content with factory calibration, temperature and bulk electrical conductivity were compared with values from the thermocouples and the TDR system (Evett et al., 2010b,c; 2011d,c; 2012c). Continued to monitor and maintain the TDR and thermocouple measurement system at the Marena, Okla., SMAP In-Situ Sensor Test Bed in cooperation with Tyson Ochsner. Conducted theoretical, laboratory and field investigations of a waveguide-on-access-tube (WOAT) soil water sensing system employing TDR technology. Designed several WOAT prototype tube segments (each 20-cm long) and tested them in water, ethylene glycol, and in sand and clay loam soils at several water contents. Conducted a field test of a 1.6-m deep multiple-segment WOAT assembly with comparison to neutron probe data during wetting and drying cycles (Casanova et al., 2011a,b,c, 2012). Helped organize the Joint Meeting of the Second International Soil Sensing Technology Conference, the Soil Physics Technical Committee Annual Meeting, and the ASA Sensor-based Water Management Community, which took place January 3-7, 2012, Honolulu, Hawaii, but were unable to attend.<br /> Utah: A $5000 grant proposal was submitted to and funded by USDA to support speaker travel to the University of Hawaii for the W2188 joint meeting with the 2nd International Soil Sensing Technology Conference held January 3-7, 2012. In Utah, a Cosmic ray Soil Moisture Observing System (COSMOS) instrument was installed at the T.W. Daniel Experimental Forest Research Site. The COSMOS instrument output can be related to soil moisture. We will be comparing our ground based soil moisture measurements to the COSMOS output. A second GPS-based instrument for estimating Snow Water Equivalent was installed 1000 m away in Docs Meadow. This instrument is operated by the University of Colorado in Boulder, CO. Collaboration with colleagues at China Agricultural University (CAU) to develop extended capability for the PHPP to measure soil dielectric for water content determination is ongoing. A modified electromagnetic sensor is being developed to couple with the electrodes within the footprint of the PHPP sensor. <br /> Washington: Applied a numerical model to predict seed-zone water contents and water potentials in late August or early September based on soil water content measured in early April. Studied the interactions of colloidal particles with the air-water interface. Quantified the effects of advancing and receding air-water interfaces on colloid detachment as a function of interface velocity. Continued our work on a numerical catchment-scale model that solves flow equations of surface and subsurface flow in a fully-integrated three-dimensional domain. The model directly interfaces with GIS data and provides algorithms for evapotranspiration and root water uptake. Tested the model by comparing simulated and observed soil water contents for a laboratory experiment on one-dimensional infiltration in a soil slab. The model successfully described the water balance and its components in each of the three experiments (laboratory, field, and catchment).Worked closely with the USDA NSERL (National Soil Erosion Research Lab) and the US Forest Service in developing the new online WEPP GIS interface. Evaluated the crop residue effects on snow distribution and the spatial variation of soil water storage for two adjacent fields near Pullman, Washington: one under NT, and the other under CT. The fields were surveyed during the winter and spring of 20072008 to assess topographic variations in snow depth, snow water equivalent (SWE), and soil water storage.<br /> Wyoming: Revamped an existing state-wide rainfall and soil moisture monitoring network of 20 sites during the summer and fall of 2011. The network sites were located in rangelands to study the annual variability in forage production in response to water availability (drought). As part of this project, plant cover, type, and biomass data were collected at the peak of the growing season in July. This is part of an ongoing three-year project, funded by the Wyoming Agricultural Experiment Station. In 2011, a new project was also initiated on the effect of coalbed methane product water on soil infiltration characteristics in the Powder River Basin (Wyoming Water Research Project funding). Soil and water samples from two sites were collected during fall 2011 to conduct preliminary laboratory infiltration studies.<br /> <br /> Milestones: Minnesota: Identified the increase in artificial drainage and land cover change as possible causes of the increase in flows within the Minnesota River Basin. Increases in precipitation have been considered the main cause for the increases in stream flow, but our results do not support this. It was demonstrated that the morphology of freezing in initially unsaturated soils consists of three zones - a fully saturated zone, an intermediate unsaturated zone with ice present, and an unsaturated unfrozen zone far from the freezing boundary. This model of freezing process was tested with laboratory data and was validated for the conditions given.<br /> Oklahoma: Develop a scientifically-sound procedure for interpolating plant available water between Mesonet sites. Create and release a new daily plant available water map for drought monitoring in Oklahoma. Discover the similarities and differences between plant available water and other significant drought indicators. <br /> Texas: A provisional patent application was filed on the waveguide-on-access-tube TDR system for sensing of soil water conduct, bulk electrical conductivity and temperature at multiple depths (Evett et al., 2011b). An SBIR Phase I grant proposal for feasibility investigation of the waveguide-on-access-tube TDR system was awarded and completed in 2011. The multiple sensor field comparison was completed in 2011 and preliminary reports made. Schwartz co-organized the symposium Measurement and Modeling of near-Surface Soil Water and Energy Fluxes: I and the coordinated poster session Measurement and Modeling of near-Surface Soil Water and Energy Fluxes: II at the ASA-CSSA-SSSA International Annual Meetings, Oct. 16-19, 2011 in San Antonio, Tex. The Second International Soil Sensing Technology Conference was held in Honolulu, Hawaii, January 3-7, 2012. Several peer-reviewed and proceedings papers were published, including a review paper on soil water sensing for water balance, ET and WUE (see publication listing). Wyoming: For 2012, we anticipate completing a modeling study on vertical water and heat fluxes in a snow-dominated forest ecosystem in southeastern Wyoming.

Publications

Impact Statements

1. CA: Degradation of soil and water resources by agricultural contaminants (including salts, pesticides, pharmaceuticals, and pathogenic microorganisms) represents a serious threat to irrigated agriculture in arid and semi-arid regions. Advanced decision support tools and simulation models are needed to develop, test, and implement site-specific soil, water, and crop management practices that optimize crop production while minimizing soil and groundwater pollution. The activities discussed above provide new knowledge about the effects of root zone contaminants on crop growth and on soil and water quality which are needed to develop improved decision support and simulation tools.
2. ID: We are developing measurement and monitoring methods addressing the characterization of mass and energy transport at the field scale using geophysical techniques easily deployable by land managers. The targeted technique will aid in the characterization and forecasting of future water resources and their temporal availability and quality, particularly in forested water-sheds.
3. IA: Percolation concepts developed in this research are being used in analysis of radioactive waste migration at the Hanford site, Richland, Washington, USA.
4. MN: Our erosion and sediment generation projects have resulted in estimates of erosion rates from ravines, bluffs and stream banks in the Minnesota River Basin. The results show that bluffs and stream banks are the most significant sources among these three since erosion from these two sources is immediately next to the stream/river flow and therefore the sediment delivery ratio to the stream/river is 1.0. As of yet it is unclear how much of the sediment generated from these two sources actually is delivered to downstream water bodies of concern, such as Lake Pepin. The increased sediment loads were associated with increased stream flow.
5. OK: This project seeks to produce (and make available on the internet) a daily plant available water map for drought monitoring in Oklahoma. Knowledge that plant available water is approaching critical minimum values, could allow farmers to change forward contracting strategies, or choose to graze out more wheat. Similarly, ranchers, facing the potential for reduced pasture, could make early arrangements to purchase hay or could sell cattle early, when prices are more favorable.
6. TX: Using various remote sensing measurements during NASA field campaigns in the past decade, we have unraveled the dominant physical controls and associated scaling rules for surface and root zone soil moisture dynamics across the globe. These findings are leading the way to improved understanding and parameterization of various hydrologic processes. Furthermore, estimating earth surface hydraulic properties using air and space-borne sensors brings the unprecedented understanding and tools for many earth sciences applications including general circulation, climate, weather, hydrology, ecology, water management, contaminant transport, and traffic models.
7. UT: Development of the Penta-needle Heat Pulse Probe falls under the 2188 Committees projected impact of, New tools, devices, analytical methods and capabilities to quantify and monitor movement of agricultural contaminants and other materials from the vadose zone to ground water and to the atmosphere.
8. WA: Our work on water content measurements and predictions at the Horse Heaven Hills helps farmers to decide whether to practice mulch tillage or no-till. Our data suggest that farmers should consider delaying their decision until as late as mid-June. If at that time, their measured soil water at the 15 to 18-cm depth exceeds 0.15 m3/m3, farmers should practice no-till and if water content is less than this amount they should practice mulch tillage.
9. WY: The status of the natural resources in the western US has a direct impact on the livelihood of local farmers and ranchers and the health and quality of life of local residents. Land use in the west also has global implications for food supply, energy supply, biological diversity, and climate. Our ability to quantify water, heat, and carbon fluxes in the soil-plant-atmosphere system provides important insights into the functioning and health of terrestrial ecosystems as impacted by management and climate. State-of-the-art sensors and computer simulation models are used to study water flow, heat transport, and gaseous exchange in both natural and managed ecosystems.

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Participants

Berli, Markus, markus.berli@dri.edu, Desert Research Inst., Las Vegas, NV; Bradford, Scott, scott.bradford@ars.usda.gov, USDA Salinity Lab., Riverside, CA;
Caldwell, Todd, todd.caldwell@beg.utexas.edu, Desert Research Inst., Reno, NV; Casey, Frank, francis.casey@ndsu.edu, North Dakota State Univ., Fargo, ND; Chief, Karletta, karletta.chief@dri.edu, Desert Research Inst., Las Vegas, NV; Evett, Steve, steve.evett@ars.usda.gov, Bushland, TX; Ewing, Toby, ewing@iastate.edu, Iowa State Univ., Ames, IA; Flury, Markus, flury@wsu.edu, Washington State University, Pullman, WA; Heinse, Robert, rheinse@uidaho.edu, Univ. of Idaho, Moscow, ID; Horton, Bob, rhorton@iastate.edu, Iowa State Univ., Ames, IA; Jones, Scott, scott.jones@usu.edu, Utah State Univ., Logan, UT; Kelleners, Thijs, tkellene@uwyo.edu, Univ. of Wyoming, Laramie, WY; Miller, Watkins, wilymalr@unr.edu, Univ. of Nevada, Reno, NV; Mohanty, Binayak, bmohanty@tamu.edu, Texas A&M Univ., College Station, TX; Nieber, John, nieber@umn.edu, Univ. of Minnesota, St. Paul; Ochsner, Tyson, tyson.ochsner@okstate.edu, Oklahoma State Univ., Stillwater, OK; Schwartz, Robert, robert.schwartz@ars.usda.gov, USDA-ARS, Bushland, TX; Simunek, Jirka, jiri.simunek@ucr.edu, Univ. of California, Riverside, CA; Skaggs, Todd, todd.skaggs@ars.usda.gov, USDA Salinity Lab., Riverside, CA; Tuller, Markus, mtuller@cals.arizona.edu, Univ. of Arizona, Tucson, AZ; Twarakavi, Navin, navin.twarakavi@dri.edu, Desert Research Institute, Las Vegas, NV; Tyler, Scott, styler@unr.edu, University of Nevada, Reno, NV; Wendroth, Ole, owendroth@uky.edu, Univ. of Kentucky, Lexington, KY; Young, Michael, michael.young@beg.utexas.edu, Univ. of Texas, Austin, TX; Zhu, Julian, jianting.zhu@dri.edu, Desert Research Inst., Las Vegas, NV

Brief Summary of Minutes

Accomplishments

Short-term Outcomes: W-2188 participants mentored >30 MS students, PhD students, and Post-doctoral researchers this year. Participants in AZ developed a new automated algorithm for multiphase segmentation of X-Ray CT data of porous media and with potential for real time segmentation and applicability in biomedical research. Participants in CA are studying ways of better management of soil salinity. Participants in ID continued work on characterizing preferential flow pathways in forested hill slopes. Participants in IA demonstrated that heat pulse probes can be used to measure sub-surface (3-mm depth and below) soil water evaporation from a bare field plot. Participants in KY applied a fourier-based experimental design allows to quantify solute leaching at the field scale despite existing spatial heterogeneity of the field soil. Participants in MN showed that vegetation colonization on point bars is a major cause for the deposition of suspended sediment and bedload in rivers and the stabilization of point bar features. Participants in NV showed that the solutions to the fractal Richards equation (FRE) exhibit anomalous non-Boltzmann scaling, attributed to the fractal nature of heterogeneous media. In NM, data were analyzed and results on soil physical and chemical properties were shared with the wastewater authorities for designing better wastewater irrigation schedule. Laboratory studies in ND indicate that estradiol associates with colloids derived from manures, which implies that they can be transport on and through soils. In OK key outcomes of this project were advances in scientific knowledge on methods to monitor soil water content and plant available water. This new knowledge was generated by the project team and shared with an audience of OK stakeholders and researchers through a presentation at Oklahoma Water Resources Research Symposium in Tulsa, OK. Participants in OR applied numerical modeling methods to demonstrate that textural contrasts between coarse and fine sands can extend the duration of first stage evaporation, thus quantifying the effect of soil heterogeneity on soil evaporation. Participants in TX developed a number of spatio-temporal scaling algorithms for various soil physical parameters and soil moisture state that may be applied for various agricultural, hydrologic, soil-vegetation-atmosphere-transfer, and contaminant fate and transport modeling and remediation strategies. In UT a key outcome has been working on a new BARD project to measure soil water fluxes using the streaming potential. Key issues there are the need to eliminate sources of noise in the signal. Experimental and theoretical investigations in WA have demonstrated that capillary forces due to the air-water interface present in soils and sediments play an important role in colloid mobilization and transport. We further found that particles containing edges experience stronger capillary forces than smooth particles and are therefore more like to be transported through soils. In WY automated monitoring of climate, snow, and soil variables continued in agricultural fields, rangeland, and forest in WY as part of several multi-investigator research projects. The data are used to inform numerical models of the soil-plant-atmosphere system to calculate water, heat, and carbon fluxes and to determine annual water and carbon balances as part of hydrological and climate studies. <p>Outputs: W-2188 participants reported authoring 173 peer-reviewed papers, 7 book chapters, 95 abstracts and proceedings papers, 18 technical reports, and 2 patent applications in 2012. AZ: 7 refereed journal articles, 2 conference article, 15 abstracts; CA: 64 refereed journal articles, 16 refereed reports, 4 book chapters, 13 abstracts, 1 patent application, 5 new computer model modules (HYDRUS related); ID: 2 refereed journal articles, 8 abstracts; IA: 14 refereed journal articles; KY: 1 refereed journal article; MN: 3 refereed journal articles, 5 abstracts; NM: 8 refereed journal articles, 3 abstracts; NV: 15 refereed journal articles, 4 book chapters, 13 abstracts; ND: 4 refereed journal articles, 2 conference papers; OK: 3 refereed journal articles; OR: 6 refereed journal articles; TX: 35 refereed journal articles, 8 conference papers, 8 abstracts, 3 book chapters, 3 patent applications; UT: 9 refereed journal articles, 1 conference papers, 21 abstracts; WA: 8 refereed journal articles; WY: 3 refereed journal articles, 3 abstracts. <p> Activities: AZ: Invested significant efforts to further improve 3D multiphase segmentation capabilities for X-Ray CT data of porous materials. To reduce potential operator bias in selection of segmentation thresholds we developed a 2-stage algorithm that applies multiphase k-means clustering to statistically seed a Markov Random Fields (MRF) image model. Besides computational efficiency and stability, the most distinct advantage of the new code is that it can handle any number of voxel classes, eliminating the need for wet dry or dual energy scans, image alignment and subtraction commonly applied in x-ray micro-CT analysis. CA: A computing system is being developed which will, for a specified geolocation, provide parameter probability distributions for soil parameters that are used in hydrologic model calculations. The system works by retrieving for the specified location USDA-NRCS soil survey data (SSURGO) and processing the data to obtain the required parameter distributions. In 2012 we have offered short (2 to 5 day) courses on how to use HYDRUS models at various locations. Over 200 students participated in these short courses. KY: Conducted a field-scale solute transport tracer experiment. Conducted a remote sensing experiment in a farmers field in Western-Kentucky with the goal to improve site-specific nitrogen fertilizer recommendations. A graduate level course in Spatial and Temporal Statistics was taught in the fall semester. Taught a lecture on The role of soils in our life to local high school (Lafayette High School) students (freshman and sophomore level), reached out to 180 students in six sessions. ID: Correlations between small-scale slope terracing and soil moisture were assessed using ground-based LiDAR and Electromagnetic Induction (EMI). The site is a north facing slope with Palouse silt loam soils continuously grazed throughout a growing season. A 1cm by 1cm resolution scan was obtained with a green laser Leica Scan Station 2. Through the use of Cyclone and Point-to Grid software the LiDAR point cloud was rendered into a high resolution digital surface model. Electromagnetic Induction scanning was used to map the electric conductivity within the site to a depth of 1m both parallel to and perpendicular to the site slope. A map of water content was then generated from these data using site-specific calibration. Correlations between LiDAR and EMI data were tested across the slope with respect to terrace morphology. Correlations between vegetation, terrace presence/absence and soil moisture were also tested. Correlations identified between surface topography and soil moisture at smaller scales (1m and 1cm) than flight-based LiDAR, can be used to improve our understanding of the spatial and temporal variability of soil moisture on micro-topographic hillslope features. Correlations of soil moisture content and length/height of hillslope terraces are also anticipated to further our understanding of watershed hydrologic yield and retention capacity, thereby increasing the accuracy of commonly used watershed-scale models. Soil moisture content and storage varies spatially across a landscape, affecting yields of dry-land crops. Common methods for measuring soil moisture disturb the soil and do not adequately represent large areas with varying topography. We estimated soil-water content using electromagnetic induction (EMI) comparing a commonly used form of conservation tillage (chisel plow) and no-till as well as three phases of a crop rotation (winter wheat, spring cereal, legume) on a split-plot design. Weekly measurements of electrical conductivity obtained using EMI were converted to water contents using a calibrated relationship including variables such as soil texture, solute concentration, and temperature. Solute concentration and temperature were routinely measured within each crop to account for variance through the growing season. Current tables for determining water retention of crops for the following season do not specify the type of tillage the crop was grown under. Since winter wheat has higher water retention for the following year and a no-till system has increased water in the vadose zone, winter wheat grown under no-till is expected to have the highest water retention for the following year's crop. Spring wheat grown under conventional tillage is expected to show the least water retained for the following year's crop. IA: A bare surface field study was performed. Three-needle heat-pulse sensors successfully characterized soil water evaporation, but some limitations were apparent for evaluation of thermal gradients nearest the soil surface. This hinders measurement of evaporation beginning from wet soil surfaces. A new 11-needle heat-pulse sensor was designed to permit improved evaluation of thermal gradients within the upper 3 mm of the soil profile. Construction of the sensor was aided by collaboration with Tusheng Ren, China Agricultural University and Joshua Heitman, NCSU. This newly-designed and constructed sensor was evaluated and it out-performed 3-needle heat pulse sensors in laboratory and field experiments. One-dimensional soil microcosms were constructed for the laboratory experiments on soil water evaporation. The heat pulse method was shown to accurately measure soil water evaporation in the soil microcosms. We performed experiments in cropped fields (corn and soybean). Heat pulse probes were placed in the soil to measure soil water evaporation, sap flow stem gages were used to measure transpiration, and eddy covariance was used to measure evapotranspiration above the crop canopy. We performed numerical modeling to evaluate the robustness of the heat pulse method for estimating subsurface soil water evaporation. KY: A field-scale solute leaching experiment was conducted to improve understanding of the impact of land use, rainfall amount, intensity and application time delay on the leaching of bromide. A remote-sensing based experiment was conducted in a farmers field in Western-KY to test the improvement of N-fertilization through the use of the GreenSeeker and derived NDVI of winter wheat. An additive state-space statistical model was adapted for the analysis of agricultural experiments. Treatments can efficiently apply non-randomly but varying periodically at different scales so that underlying soil heterogeneity effects can be compensated in the analysis. MN: One project maps rates of sediment production from near-channel areas in three watersheds in MN. The watersheds include the Buffalo River, Elm Creek, and the Whitewater River. For all 3 watersheds, field investigations have been conducted collaboratively by the University of Minnesota (UofM) research team and by teams from the MN Dept of Natural Resources. Investigations have involved geomorphic assessments of stream channels. Channel cross-sections, channel materials, and vegetative cover conditions have been acquired from numerous locations along all major channels. Sites for monitoring channel erosion with erosion pins have also been set in place. The role that vegetation plays in the development and stabilization of sediment point bars in channels is being investigated by the UofM team. The aging of the woody vegetation provides a way to determine the sediment deposition rates on the point bars. The history of sediment deposition in flood plain areas is also being quantified. A method using GIS data layers along with aerial photographs to derive data for channel erosion prediction models is currently being tested with the acquired field data. The second project involves the characterization of the interactions between Minnehaha Creek, an urban stream in the Twin Cities Metro Area, and the underlying groundwater system and the surface water sources including wetlands and lakes within the Minnehaha Creek watershed. Flows in the Creek have been analyzed to evaluate baseflow and stormflow conditions. The flows are found to be quite flashy, largely due to the fact that much of the watershed is developed and stormwater from throughout the watershed is conveyed directly into the Creek. The flashy flows and high discharges during stormflow conditions have led to an over-widening of the channel, resulting in poor conditions for aquatic habitat, thereby leading to the current impaired biota designation for the Creek. Application of a conceptual hydrologic model analysis to flow data indicates that only a small fraction (less than 1%) of the watershed groundwater system is contributing flows to the Creek. Various field assessment techniques are being applied including temperature profiles in the hyporheic zone of the creek, seepage meter measurements at various locations along the creek, piezometric head measurements along transects perpendicular to the creek, and water sampling for stable isotopes to conduct end-member mixing analysis. The field data acquired to date indicates that groundwater contributes to streamflow in the upper part of the watershed, but in the lower portion the Creek appears to be losing water to the groundwater system. It is not clear at present what might be most affecting the rates of water loss from the Creek. Candidate causes are the natural setting, the pumping of water from municipal wells in the area, and the subsurface stormwater and municipal sewer piping infrastructure in the watershed. These candidate causes will be aspects that will be investigated further. NM: Comparative effects of the compensated (under water stress conditions using drip-irrigated partial root zone drying (PRD) techniques) and non-compensated (no water stress) root water uptake pattern were evaluated for chili plants (NuMex Joe Parker; Capsicum annuum). Results suggest that chili plants under these two drip-irrigated PRD treatments could compensate for water stress in one part of the vertical or lateral root zone profile by taking up water from less water stressed parts of the vertical or lateral root zone regions, without affecting transpiration or photosynthetic rates to meet peak water demand. No significant differences were noted in the root length distributions and plant heights between PRD treatments and control. Either of the two drip-irrigated PRD techniques have a great potential to be adopted as water saving practices in chili production especially for environments with limited water. The timing and amount of irrigation water is critical to the optimum production of pecans in semiarid, irrigated agriculture systems. However, there are few tools available to managers to measure or estimate water use compared to deep percolation (DP) below the root zone. The RZWQM2 model was compared to the daily water balance method at two floodirrigated mature pecan orchards, with different soil textures and depths to water table, in the lower Rio Grande Valley near Las Cruces, New Mexico. At sandy loam Site 1, 25% to 29% of the applied water percolated below the root zone. In contrast, at silty clay loam Site 2, total estimated DP was 37% and 35% of the total water applied. Different soil textures and water table depths afford managers to use the model to address water management issue to minimize DP while optimizing pecan production. Information on soil hydraulic properties, spatial variability, and relation to soil chemical properties is crucial for making management decisions for lands affected by anthropogenic activities. In situ infiltration tests were conducted at the West Mesa Land Application Facility near Las Cruces, NM, to determine the spatial variability of hydraulic properties and quantify the macroporosity using tension infiltrometry. Kriged maps of Ks showed that classes I, II, and III were concentrated at the northeast and southwest sides of the study site, where higher Na+ was detected, and classes IV and V were at the center of the study site, corresponding to lower Na+ levels. Significantly lower macroporosity was observed in the area were Ks was lower and Na+ content higher. Therefore, additional increases in Na+ could further decrease the Ks and macroporosity and may affect water uptake by the native vegetation. Change in the wastewater application pattern by applying higher amounts of wastewater in the areas where soil Na+ concentrations are lower would be beneficial for sustaining soil quality and plant community. ND: In 2012, experiments were conducted to determine how dissolve organic carbon (DOC) and colloidal organic carbon (COC) derived from soil and manure affects the fate and transport of the natural estrogen, 17ß-estradiol (E2). This compound, E2, can disrupt the endocrine systems of aquatic organisms at very low concentrations. Radiolabelled (14C)-E2 was filtered with pure water and different combinations of soil and manure derived COC/DOC solutions. These experiments were designed to see whether the 14C-E2 preferentially associated with the different organic carbon fractions (i.e. COC or DOC), and whether these organic carbon fractions affected E2 persistence and binding to soil. Additionally, models were developed to help identify and potentially predict the fate and transport of the sulfate and glucuronide conjugates of E2. Estradiol is very insoluble and in order for an animal to excrete it from their body, it must first be made soluble by attaching a sulfate or glucuronide to the E2 molecule. The attachment of the sulfate (E2-S) or glucuronide (E2-G) to the E2 molecule is called conjugation. Between 60% and 90% of all estrogens excreted from farm animals are in the forms of conjugates. Experimental observations from soil batch experiments were used to develop fate and transport models of E2-S and E2-G and their metabolites. The model was solved numerically and applied inversely to the experimental observations using a global optimization method to quantify the sorption and transformation parameters of E2-S and E2-G and their metabolites. A new laboratory analytical procedure was developed that only requires liquid chromatography and liquid scintillation to accurately quantify and qualify 14C-E2 and its metabolites in laboratory experiments. Field observations from shallow wells installed in a grid pattern were correlated to surface measurements from a quarter-section, irrigated field. Surface topography, electrical conductivity and a suite of soil nutrient and micronutrients were correlated with ground water quality measurements. Multivariate statistical and geochemical analyses were used to determine how ground water influenced surface soil properties. NV: We examined Feedback between fast cyclic biotic and slow cumulative pedogenic processes on arid alluvial fan systems results in a heterogeneous landscape of interspace and canopy microsites. We used a soil chronosequence in the Mojave Desert and high spatial resolution measurements along transects radiating from canopies of shrubs to assess the extent of biotic and abiotic processes and the heterogeneity of soil properties. Results showed higher conductivity under vegetation regardless of surface age, but it was more conspicuous on older, developed soils. Soil properties at distal locations 25 times the canopy radius had no significant spatial correlation. The extent of the biotic influence of the shrub was 1.34 times the canopy radius. Hydraulic properties were weakly correlated in space, but 75% of the variance could be attributed to sand content, soil structure grade, mean-particle diameter, and soil organic material. Non-Boltzmann Scaling of Water Flows in Unsaturated Soils: The traditional Richards equation implies that the wetting front in unsaturated soil follows Boltzmann scaling, with travel distance growing as the square root of time. This study proposes a fractal Richards equation (FRE), replacing the integer-order time derivative of water content by a fractal derivative, using a power law ruler in time. Nutrient Hot spots in Forest Soils along the Sierran Front to the Cascades: Biogeochemical hot spots are of interest due to the potential influence on nutrient transport from terrestrial to aquatic systems. Previous research has identified the presence of hot spots, however the spatial scale and frequency of occurrence remain uncertain. Direct (soil cores) and passive sampling (resin capsules and lysimeters) was used to investigate the seasonal and annual spatio-temporal distribution of nutrient hot spots along the Sierran front northward to the base of the Cascades. Our objectives were to assess their presence, chemical composition and geographic distribution in alpine forest ecosystems. Elevated nutrient concentrations (hot spots) of ortho-P, Ca2+, Mg2+, NO3-N and NH4-N were identified at least once per sampling grid per year. However, they rarely occurred at the same sampling point over two consecutive years; only four of the 256 resin capsule grid points (1.5%), one of 96 first fall precipitation capsule grid points (0.01%), and one of the 128 resin lysimeter grid points (0.78%) exhibited similar trends over both years of study. Moderate and extreme nutrient outliers in the overlying O horizon and directly underlying soil matrix were only detected in four samples of the 126 cores collected. The possibility remains that a number of these nutrient hot spots have the potential to infiltrate directly from the terrestrial to aquatic matrices impacting hydrologic systems, whereas others may remain in place and available for opportunistic biological species. Root-Induced Changes of Soil Physical Properties Using Synchrotron X-ray Microtomography (CMT) and Micromechanical Simulations: In this study, we sought to quantify rhizosphere physical properties by (1) employing CMT to visualize physical root-soil structure interactions, (2) simulating root-induced structural alterations using micro-mechanical approaches (analytical, finite element modeling), and (3) estimating changes in rhizosphere hydraulic properties based on CMT imaging and modeling. Watershed Characterization Using Geomorphic Mapping and Field-Measured Hydraulic Properties: We characterized watersheds by a physically-based approach that can be used in a rainfall-runoff model to improve surface runoff predictions using geomorphic mapping and a combination of field methods and correlation approaches. In addition, characterization of hydraulic properties at the microsite was also carried out. Effects of Fire on Soil Properties: In the western U.S., the frequency, severity, burned acreage, and duration of wildfires have increased in the past 35 years, leading to damaging floods, extensive erosion, and higher sediment yield and debris flow. Negative watershed effects are attributed to fire-induced changes in soil adsorption capacity and hydraulic properties, particularly decreased infiltration capacity. The aim of this research was to characterize fire-induced soil structural alteration processes and relate them to soil hydraulic properties. Large Weighing Lysimeters to Investigate Near-surface Interactions of Soil, Water, Biota, and Atmospheric Sciences: This meso-scale facility is devoted to investigating the near-surface interactions of soil, water, biota, and atmospheric processes that affect desert environments similar to those found in the southwestern United States such as the Mojave Desert and will bridge existing eco-scale, laboratory, and micro-scale research efforts. Three lysimeters are cylindrical (2.258 m diameter x 3 m deep), and one is square (2 m x 2 m x 3 m deep). The lysimeters were designed to investigate: 1) landscape dynamics, restoration, and water balance; 2) carbon sequestration; and 3) characteristics of soil properties at different scales. Effects of Vehicle Traffic on Soil Physical and Mechanical Properties: Although the effects of heavy vehicle traffic on soil physical and mechanical properties are well documented, surprisingly little is known about the actual processes involved. Subsequently, there is still a good amount of speculation about how to protect soil best from being irreversibly compacted. Goal of this research is to shed light on the fundamental processes that change physical and mechanical properties of agricultural as well as forest soils due to heavy vehicle traffic. Participants co-convened two meeting sessions. OK: Tested and released to the public a new plant available water-based drought monitoring system for OK. Managed and expanded the Marena OK In Situ Sensor Testbed (MOISST) in support of NASAs upcoming Soil Moisture Active/Passive (SMAP) satellite mission. Began research collaboration with NASAs AirMOSS remote sensing mission for measuring root zone soil moisture. OR: Quantifying earthatmosphere gas exchange is a challenging, yet important problem that is made more complicated by the large number of mechanisms that contribute to this process. This work investigates one mechanism controlling non-diffusive gas transport from high-permeability media that is driven by natural diurnal thermal gradients in the upper vadose zone. We quantified CO2 migration through 1-m long columns packed with two different grain sizes: sand and large soil aggregates  both dry to eliminate chemical reactions. The bottom ends of the columns were exposed to 2000 ppm CO2-enriched air and the CO2 concentration profiles along the columns was continually monitored. The columns were exposed to two different thermal gradient regimes: isothermal conditions and a range of typical nighttime thermal gradients that are known to lead to unstable density profiles. Under isothermal conditions, and regardless of grain size, diffusion was the major mechanism for surfaceatmosphere gas exchange. Under nighttime conditions, the prevailing mechanism depended upon matrix air permeability: Diffusion controlled CO2 transport in the low permeability matrix, whereas thermal convection governed transport in the high permeability matrix. Venting by thermal convection caused a CO2 flux of up to two orders of magnitude higher than the diffusive flux. Such a mechanism may be implicated in a number of environmental settings. In soil, thermally driven convection can contribute to tilled soil aeration and is likely one of the mechanisms associated with rapid CO2 exchange that is commonly noted to follow tillage. With respect to the global CO2 output, thermal convective venting is shown to be a permeability-limited mechanism with high gas exchange potential and a continuous diurnal presence. Its characteristic spatial scale could include, geologic sources via fractured rock surfaces, soil cracks, mine leach heaps, and rock-fill embankments. Hydrophobicity is a common condition to many if not most soils. Over 2400 manuscripts have been published on the causes of hydrophobicity, possible amelioration techniques for land used in agricultural production, and the environmental consequences of hydrophobicity, including preferential flow and high erosion rates following forest fires. Most of this prior work investigated soils exhibiting strong hydrophobicity. Mild hydrophobicity, however, can also cause significant problems in certain agricultural settings. It is this area of mild hydrophobicity that this project aims to understand. The project field site is based in the Columbia Basin of OR, where growers are reporting increasing problems with soil wettability with fields showing typical hydrophobic behavior such as water ponding and high soil erosion rates. Traditional ameliorations techniques have not solved the problem. Current management techniques used for crop success is near-continuous irrigation to sustain soil wetness. This practice uses extreme amounts of water and leads to deep infiltration of agrochemicals. The project goals are to determine the source of hydrophobicity, investigate possible methods for ameliorating this site, and prevent degradation of new land being put into production. We have investigated the physical mechanisms that control hydrophobic field-scale behavior and identified two elements: (1) An apparent scale dichotomy is still under investigation - Soil at the laboratory scale is only mildly hydrophobic, but at the field-scale exhibits high wetting problems; (2) Erosion of hills is generated by the mechanical accumulation of soil particles into irrigation droplets that roll downhill once coated with soil particles. Theoretical models to explain this mechanism are being developed. Two hypotheses are being tested. (1) We are investigating the potential development of capillary barriers~ 1 cm below the surface caused by capillary aggregation of the hydrophilic sand portion. These capillary barriers may be what are holding up the ponded water. (2) We are investigating the role of organic matter structure to control reversible hydrophobicity. This is based on a relatively new understanding of organic matter structure at the OM-mineral interface in the presence of water. TX: Organized sessions in American Geophysical Union 2012 Fall Meeting, Understanding Process Dynamics in the Critical Zone at Different Scales. The Agronomy Society of America Sensor-based Water Management Community, led by Evett, co-sponsored the Second International Soil Sensing Technology Conference, 3-7 January, 2012 in Manoa, HI. We continued collaboration with the Soil Moisture Assessment Project (SMAP) team in the inter-sensor comparison at the Marena OK In Situ Sensor Testbed (MOISST), which began in May 2010; and we have cooperated with Mike Cosh in the Hydrology and Remote Sensing Laboratory (HSRL), Beltsville to plan that and other work, and with Tyson Ochsner of OK State Univ to maintain the systems. This work is tied to NASAs planned Soil Moisture Active Passive (SMAP) Mission that will make global estimates of the soil water present at the Earths land surface. We have an ongoing soil water sensor comparison study going on at Bushland in a parallel effort. We became part of the COSMOS network of soil water sensors that use neutron flux arising from cosmic radiation. Equipment sent to us was installed in April 2012 and verified as functioning by the COSMOS team. Evett presented Soil Water Sensors: Problems, Advances and Potential for Irrigation Scheduling on 14 March 2012 to the Ogallala Aquifer Program Workshop in Garden City, Kansas. The Sensor-based Water Management Community also organized a Symposium titled Sensor-based Water Management: Sensors and Algorithms at the 2012 Agronomy Society meetings in Cincinnati, OH. Evett facilitated a USDA-NRCS AquaSpy training workshop on 16 May 2012, and later worked with AquaSpy personnel to install their soil water sensor in an irrigated field so that data could be put online for the NRCS personnel to view and compare with neutron probe data. Evett coordinated and led a workshop of the Middle East Regional Irrigation Management Information Systems (MERIMIS, www.merimis.org) project partners in Jerusalem on 5 September 2012 and worked with MERIMIS partners with the National Centre for Agricultural Research and Extension (NCARE) in Jordan, with the Agricultural Research Organization (ARO) in Israel and with Palestinians from the West Bank to analyze crop water use (soil water and energy balances) and irrigation research data and improve the weather station network (21 stations) with soil water sensors and 2-D sonic anemometers. Evett organized and directed a week-long training program for professionals from the Ministries of Water in Israel, Jordan and the Palestinian Authority on Water Resource and Economic Modeling in Jerusalem, September 9-13, 2012. The U.S. State Department funded the training through the USDA-ARS Office of International Research Programs. The SWAT model and the MYWAS model were introduced, as well as upcoming extensions of SWAT involving evapotranspiration modeling and linkage with MODFLOW. Evett and Schwartz participated in the American Association for the Advancement of Science  Uzbekistan Academy of Sciences joint workshop. The workshop was organized to identify science priorities and possible joint research programs to be funded in the future. Schwartz presented Optimizing the use of limited water in agricultural systems, and Evett presented Irrigation Science and Water Quality Challenges in Uzbekistan. Evett presented Irrigation Scheduling by ET and Soil Water Sensing to 50 trainees in an hour-long Irrigation Seminar at the 2012 Irrigation Show and Education Conference on 5 November 2012 in Orlando, FL. Evett presented A Waveguide-On-Access-Tube (WOAT) TDR Sensor for Deep Soil Water Content, Bulk EC & Temperature in the ASA Symposium Sensor-Based Water Management: Sensors and Algorithms on 22 October 2012 at the ASA-CSSA-SSSA International meetings in Cincinnati, Ohio. Evett co-organized the ASA Symposium Sensor-Based Water Management: Sensors and Algorithms held on 22 October 2012 at the ASA-CSSA-SSSA International meetings in Cincinnati, Ohio. UT: iUTAH, innovative Urban Transitions and Aridregion Hydro-sustainability, is a statewide effort dedicated to maintaining and improving water sustainability in Utah. Funded by the National Science Foundation's EPSCoR program (Experimental Program to Stimulate Competitive Research) this five-year, $20 million competitive award will assist in building the human and research infrastructure needed to sustainably manage Utah's water resources. The award went into effect August 1, 2012. iUTAH will build critical observatory and modeling facilities across watersheds; create trans disciplinary research teams from many Utah institutions, government agencies, and the private sector; and enhance expertise and diversity through strategic recruitment of faculty and students. The novel and transformational activities of iUTAH include: the development of fully integrated hydrologic and social sciences observatories that encompass whole watersheds along an urbanization gradient; collaborative activities to create a community of scholars across the state to address sustainability of coupled human-natural systems; and integrated education and outreach activities such as participatory and collaborative modeling efforts to communicate and collaborate with stakeholders and policy makers. The Logan River Watershed infrastructure will contribute to monitoring the ecologic/climate/hydrologic system in the Wasatch Range Metropolitan Area (WRMA) to better understand biophysical and hydrologic processes, test models of ecosystem processes, assess dynamics and availability of future water resources, and provide baseline data as a foundation for future interdisciplinary projects. A second major project in collaboration with Markus Tuller (U of Arizona) is aimed at the development of economically feasible surface chamber techniques for measurement of greenhouse and regulated gas emissions from animal feeding operations. USU has developed a control system for the 12 chambers, which will integrate measured data from a variety of sensors into a handheld computer where the gas analyzer data is processed. This fully integrated system can be split to two 6-chamber systems where multiple gas analyzers are available. A dual chamber system has been tested, showing excellent correlation with both chambers measuring a common sample. The expanded system will be constructed and testing in early 2013. Washington: In the Hanford 300 Area, near Richland Washington, 58,000 kg uranium (U) has been released to the subsurface through waste processing ponds between 1943 and the 1980s. Today, the total U concentrations in the groundwater continue to be higher than the EPA standard of 0.13 microM. Our work focused on studying why the U concentrations in the pore waters remained that high, despite continuous flushing of the sediment by river water. We quantified U release and release rates when sediments equilibrated with river water introduced into the capillary fringe. We hypothesized that U release and release rates increase proportionally with the amount of water diluting the resident pore waters. We showed that there was an initial rapid release of 6 to 9% of the total U from the sediment when river water imbibed the sediments. Our results indicate that the release of the majority of the U (>90%) from the contaminated sediments was kinetically controlled. The diffusion-limited release of U, as well as the removal of U from the solution phase when limited water inundates contaminated sediments, may explain the sustained release of U from contaminated Hanford 300 Area sediments. We have developed a new version of Online WEPP GIS interface, in collaboration with the water erosion research team at the USDA NSERL, and carried out a case application study to evaluate the performance of the Online WEPP model. The interface allows watershed structure and topographical inputs to be automatically generated from the USGS 30-m National Elevation Data, soil inputs retrieved from the USDA NRCS SSURGO database, and land use and management inputs selected from the WEPP database based on the USGS land cover. Additionally, surface cover and soil properties of the WEPP management file and soil file may be customized to represent site-specific conditions. Daily climate inputs are generated from the long-term climate parameters using CLIGEN, an auxiliary stochastic climate generator. WY: Work continued on the monitoring of rainfall, soil moisture, and biomass production at 15 rangeland sites across WY. PhD student Tegenu Engda is using the data to study the annual variability in forage production in response to water availability (drought). Work also continued on the impact of saline-sodic coal bed methane product water on soil infiltration in WYs Powder River Basin. <p>Milestones: KY: The group developed a sound experimental approach for studying water and solute transport phenomena based on soil mass concentration. The next step is learning to understand the behavior of solute concentration obtained from solution samplers. Spatial and temporal behavior of CO2 flux at the land surface and its variability structure in both space and time domain have been quantified. Temporal behavior of CO2 flux is strongly temperature and soil water content driven. The next step is to identify the processes determining the spatial heterogeneity of these fluxes in arable and pasture soils. Crop-sensor-based nitrogen fertilizer application in winter wheat increases farmers profits. The next step is to incorporate a flexible zone-specific calibration of the application algorithm that considers the inherent spatial heterogeneity of field soils. MN: Acquired in-field and aerial photographic data on erosion of streambanks on three river systems in MN. These data are being used to quantify erosion rates for these rivers and to prioritize locations for channel restoration. Mapped the surface water sources and subsurface sources of streamflow for the Minnehaha Creek watershed and acquired stable isotope for analysis of proportions of streamflow contributed by the various sources of surface water and subsurface water. These data are being used to determine the flux of water through the streambed of the Creek. New Mexico: The second phase of wastewater project was completed. For the SCRI project, most of data collection for year 3 and analysis were completed. OK: Quantified the improvement in the accuracy of the Mesonet soil water content estimates resulting from improved characterization of the soil physical properties at each site and depth. Created and released a new daily plant available water map for drought monitoring in OK. TX: Developed fundamental understanding of dominant physical controls for soil moisture dynamics ranging from pore, field, catchment, watershed, to region. A hydraulically driven system for pushing an access tube into the ground while auguring from within the tube was designed built and tested. The system was designed to be easily added to an existing Giddings Company hydraulic coring machine. It will be useful for installation of the down-hole cylindrical TDR system described previously. Limited field tests of the installation and operation of the TDR waveguide on access tube (WOAT) down-hole soil water and bulk electrical conductivity sensing system were conducted. Installation in moist soil with low soil strength proceeded without problem when a trip arrangement was used to prevent lateral forces from causing the multi-segment WOAT cylinder to move laterally, causing a void to development between the cylinder and soil. Waveform and bulk EC data were collected from all segments over periods of several weeks and compared with neutron probe readings. Installation into dry soil with great soil strength caused longitudinal compression of the plastic WOAT segment bodies, resulting in installation and circuit failure. A redesign is in progress to render the WOAT segments sufficiently strong under compressive force during installation to make compression negligible. Field tests of several local soil water, temperature and bulk electrical conductivity sensors were concluded. Sensors in the test bed at Bushland included the Decagon 5TE, Stevens HydraProbe, Acclima ACC-TDT, Campbell Scientific CS616 and CS655, Delta-T SM200 and conventional TDR. WY: The University of Wyoming received a $20M EPSCoR grant for The Wyoming Center for Environmental Hydrology and Geophysics. My contribution includes snow-soil monitoring in the Medicine Bow Mountains and the modeling of soil-plant-atmosphere interactions.

Publications

Impact Statements

1. CA: Degradation of soil and water resources by agricultural contaminants represents a serious threat to irrigated agriculture in arid and semi-arid regions. Advanced decision support tools and simulation models are needed to develop, test, and implement site-specific soil, water, and crop management practices that optimize crop production while minimizing soil and groundwater pollution. The activities discussed above provide new knowledge about the effects of root zone contaminants on crop growth and on soil and water quality which are needed to develop improved decision support and simulation tools.
2. ID: The major outcomes/impacts can be summarized as follows: (1) developed a new characterization methodology for seasonal soil moisture distributions; (2) tested new methods of quantifying surface hydrology in complex terrain; and (3) we demonstrated that porous media may be engineered for plant growth applications in planetary gravity.
3. IA: We demonstrated that heat pulse probes can be used to determine sub-surface soil water evaporation. We have made measurements in laboratory microcosms, bare fields, and cropped fields. These findings have broad importance within the soil physics and vadose zone hydrology scientific communities. Our measurements of soil water evaporation are useful to the micro-meteorological community. The measurements of soil water evaporation from sub-surface depths will also help climate modelers to develop new algorithms for partitioning near surface energy and water balance components.
4. KY: Using a flexible calibration of the GreenSeeker crop sensor for nitrogen fertilizer application in winter wheat, an increase of 3 bu/ac in yield could be obtained. This increase is expected to be larger under more favorable weather conditions. The year 2012 was extremely dry in the southeastern U.S.. The yield increase would not only mean economic benefit to the farmer but also positive effects on the environment. Overall, spatial site variability in wheat yield is the main yield limiting factor, and better understanding soil impact on crop growth processes is a key in improving soil and crop management systems.
5. MN: Quantification of erosion rates on streambanks has been completed on dozens of sites in three river systems in Minnesota. Those results are being combined with economic analysis to provide a prioritization of sites to be restored. This will help with extending the resources that are available for riverine restoration in Minnesota. The sources of flow for Minnehaha Creek have been determined to be largely from surface runoff. The groundwater contribution to the streamflow is limited. It remains to determine as to what is causing the limitation to the groundwater contributions. This information will be helpful to the Minnehaha Creek watershed district in assessing the approaches for managing stormwater, infiltration, and channel flows.
6. ND: Topographic depressions have significant saline and sodic conditions due to upward flux from shallow groundwater. This is of particular interest in North Dakota, where precipitation has increased over the past 20 years resulting in the redistribution of soluble salts in the young soils of North Dakota. Today there are over 5 million acres affected by salinity and or sodicity, and this study can help determining the extent of this problem and developing management strategies. Also, studies showed that 17ß-estradiol was observed in floodwaters in the Fargo-Moorhead community along the Red River of the North. The observations from the floodwaters indicated that 17ß-estradiol come from animal agriculture and/or wildlife habitat that had been flooded.
7. NM: The analysis of chemical data showed spots with high and low chemical composition and positional similarity of variations of hydraulic conductivities and soil electrical conductivity and soil sodium content. The contour maps of soil properties along with their spatial structures can be used in making better future sampling designs and management decisions in the west mesa site irrigated with treated wastewater. The project-2 results demonstrate that about 25-37% of water can be lost to deep percolation. The results from project 1, 2 and 3 can be used to improve the irrigation scheduling for efficient use of limited fresh water in southern New Mexico.
8. OK: This project led to the creation of an online system delivering daily plant available water maps for drought monitoring in Oklahoma. Knowledge that plant available water is approaching critical minimum values, could allow farmers to change forward contracting strategies, or choose to graze out more wheat. Similarly, ranchers, facing the potential for reduced pasture, could make early arrangements to purchase hay or could sell cattle early, when prices are more favorable.
9. TX: A significant impact of our research is innovative use of satellite remote sensing as a tool to study soil moisture, soil hydraulics, and evapotranspiration. This work has impacted a wide spectrum of earth sciences including hydrology, water management, crop production, climate forecasts, drought assessment, flood prediction, groundwater recharge estimation, and pollution. Our studies on the transport of pollutants have demonstrated how reactive contaminants move through heterogeneous unsaturated media under various boundary conditions. This will lead to new and more efficient bioremediation methods to clean pollutants at contaminated sites.
10. UT: Development of the Penta-needle Heat Pulse Probe falls under the 2188 Committees projected impact of, New tools, devices, analytical methods and capabilities to quantify and monitor movement of agricultural contaminants and other materials from the vadose zone to ground water and to the atmosphere. The infrastructure under the new iUTAH project will contribute to monitoring the ecologic/climate/hydrologic system in the Wasatch Range Metropolitan Area (WRMA) to better understand biophysical and hydrologic processes, test models of ecosystem processes, assess dynamics and availability of future water resources, and provide baseline data as a foundation for future interdisciplinary projects.
11. WA: At environmentally relevant concentrations in soils and sediments, chlorpyrifos, a hydrophobic organic insecticide, showed strong adsorption that correlated significantly with organic matter content. Our work at the Hanford 300 Area, where a U plume exists, showed that during changes of the Columbia River stage, capillary fringe sediments become flooded by river water, which is not in chemical equilibrium with the sediments. Our experiments showed that during flooding, U is being released from sediments. The release is diffusion-limited and the kinetics can explain the sustained release of U from contaminated Hanford 300 Area sediments.
12. WY: One article published described how Hydra impedance sensor measured water content and temperature in frozen soils can be used to determine in-situ soil water retention. Comparison with laboratory measured soil water retention data showed that the best results were obtained for Hydra sensors installed at shallow depths where winter freezing was most severe, resulting in a relatively wide range of calculated soil water pressure heads.

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