Duration: 10/01/2015 to 09/30/2020

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Statement of Issues and Justification

A. The need as indicated by stakeholders.

Agricultural practices affect air, soil, and water quality for both rural and urban communities. The impacts flow both ways. Activities in urban settings affect soil and water quality for rural and agricultural use, while public concern and regulatory authority to protect the environment impel efforts to preserve and improve environmental quality. Efficient management and effective regulation will optimize environmental and health protection without crippling the economy, rural or urban. The focus of Multistate Project NC-1187 is the behavior of particulate matter in size ranges capable of movement through soil, air, and water. Although this encompasses sizes from silt (2 - 50 µm) to the sub-micrometer range, nanoparticles are amongst the most reactive particles in the environment, and advanced analytical methods are needed to study them. Natural nanoparticles in soil, water, and air must be understood to the point that their characteristics and behavior can be controlled so that this natural resource may be more fully utilized.

Agricultural practices also create and disperse synthetic nanoparticles. The environmental abundance of nanoparticles produced by agriculture must be understood and any negative effects mitigated. Echoing this view is that of numerous leaders from government, industry, environment and academia, who have called for extensive research on identifying and assessing the potential risks of nanomaterials to human health and the environment (Service, 2005). According to Roco (2011), nanotechnology will have a $3 trillion impact on the global economy by 2020. The proposed budget of the National Technology Initiative for 2016 is about $1.5 billion, of which $7.3 million is projected for the USDA National Institute of Food and Agriculture (http://www.nano.gov, accessed on 6/7/2015). After the initial exploratory phase, which spanned between 2001 and 2010, the scientific community is immersed in the second phase of nanotechnology development characterized by an increased use of nanotechnology in non-traditional areas such as agriculture (Roco, 2011; Liu and Lal, 2015). Agricultural and food systems poised to benefit from nanotechnology (e.g., Liu and Lal, 2015; Servin et al., 2015), and have the research expertise and infrastructure in the land grant university system to determine the risks and benefits of nanoparticles. Project NC-1187 has been able to extend that expertise and infrastructure to national user facilities that make state of the art instrumentation and computer power available to our focus on particulate matter in air, soil, and water. Continuing this project will allow us to reap the benefits of the contacts we have established and expertise we have gained in the past.

Particulate matter in the air of rural and agricultural regions has a complex array of sources that are both primary (direct emissions) and secondary (formed in the atmosphere from reactions of gaseous chemicals). In order to understand the context of agricultural emissions contributing to particulate matter and the effects of particulate matter on agricultural production, air quality, and climate, more information is critically needed on the primary and secondary particle sources. Chemical tracers can be used to assess the origins and transformations occurring in the atmosphere, and put into context whether aerosols in agricultural regions truly are a result of agricultural activities, or may be due to natural emissions, fossil fuel use or extraction, and other urban or industrial activities. Development and application of novel technologies including the use of synchrotron radiation, field instrumentation, and data analysis approaches are needed by the research community and stakeholders to understand the sources and consequences of this particulate matter.

B. The importance of the work and the consequences if not done.

The reactivity of soils with respect to plant nutrient elements and environmental toxins is to a very great extent dependent on reactions that involve particles with diameters of tens of micrometers or less (silt, clays, microbes, nanoparticles). Because these fine particles in soils are contained in a very complex mixture, it is often difficult to gain a mechanistic understanding of processes governing the retention and mobility of many chemical species in soils by traditional techniques. For example, it is well known that phosphorus is associated with fine particles (Hanley and Murphy, 1970), but the exact chemistry of these particles is not well understood. Recent work has demonstrated the utility of synchrotron x-ray microprobe spectroscopy for the study of the chemistry of P in the fine fraction of soils (Kizewski, et al, 2011). Copper, zinc and lead are enriched in the fine fraction of soil, and particle size is an important factor for the bioaccessibility of these elements (Madrid et al., 2008; Baker et al., 2012; Baker et al., 2014). Ferrihydrite, a common nano-sized iron-bearing mineral in soils, was recently shown to bind tightly to C, more so when it was coprecipitated with ferrihydrite rather than sorbed on ferrihydrite (Chen et al., 2014). The complexation of C with particles in soils is a major mechanism for sequestering C, preventing it from being emitted into the atmosphere.

A mechanistic understanding of the role of particle size in mobility and bioaccessibility requires a detailed understanding of the chemistry of soil particles at a scale that is only possible using advanced spectroscopic and microscopic instruments. Recently questions concerning the environmental fate of nanoparticles arising from agricultural operations and from the manufacture, use or disposal of consumer products have arisen. Little is known about the toxicology and environmental behavior of these particles. These particles are very difficult to study because the particles are < 100 nm. The NC-1187 group is well poised to address the problems presented by the analytical difficulties that nanoparticles present. Our current access to synchrotron sources and the cooperation that has developed among members will serve to help solve the difficult problem of completely characterizing nanoparticles with a focus on their environmental and agricultural impact. Without the combined efforts of the NC_1187 membership, agricultural research is at risk of falling behind in terms of using state-of-the-art instrumentation to solve problems related to particulate behavior in the environment. The availability of nutrients in sustainable systems depends on reactions at particulate surfaces that often must be observed at the microscopic scale. The transport of toxic contaminants is governed by the movement, dissolution, and nucleation of particulate matter. Microscopic and spectroscopic methods are needed to follow such particles, to determine their static and dynamic composition, and to determine their availability to living organisms. The situation may be likened to the current ability to characterize microbial communities in natural systems by the analysis of genetic material. Without the application of molecular tools, we will not have the required knowledge to advance agricultural systems to minimize inputs and contamination while optimizing production and economy.

C. The technical feasibility of the research.

A common thread that runs through much environmental research is the importance of processes that operate simultaneously on different spatial and temporal scales. For instance, major questions surround particulate matter affecting rural air, soil, and water quality. The technical feasibility of applying synchrotron-based methods to a wide range of sample sizes and chemical compositions is amply supported by the current scientific literature. The utilization of a combination of techniques to accomplish full characterization of particles and to relate these properties to behavior in complex systems has become increasingly important and successful. We will extend these tested approaches to agricultural systems.

D. The advantages for doing the work as a multi-state effort.

There are several advantages in doing this project as a multi-state effort. First, particulate matter (PM) is transported across state and regional boundaries by both air and water making it a regional rather than local problem. Second, just as urban PM emissions vary considerably from one metropolitan area to another, we can expect rural PM emissions also vary because livestock industry, crops, farming practices, soils, and water chemistry vary regionally. Third, the central focus of this project (integrated modern instrumentation, including synchrotron microspectroscopy) demands extensive cooperation among members: sharing experience with specific facilities and analytical techniques, and sharing disciplinary expertise (soil, water, and air chemistry, microbiology, physics, etc.). Fourth, this project will promote the use of synchrotron sources to push the envelope in terms of micro-spectroscopic characterization of particles and will integrate synchrotron techniques with other state-of-art-tools provided by national labs and universities (Anderson and Hopmans, 2013; Udawatta et al., 2013). Fifth, project participants will share samples and data for multiple analyses, and will work to produce an integrated investigation sample set or experimental site.

In the past, synchrotron research by soil scientists primarily focused on industrial contaminants, i.e., metals and metalloids. There are many opportunities now with micro-focused techniques to study agricultural contaminants such as metals, elements like carbon and organic matter dynamics which are critical in addressing global climate change, phosphate and other nutrients in soils. This approach will link more basic soil science with applied soil science, particularly in the area of nutrient management. Finally, the members have already established an excellent record of multi-state collaboration.

This project will enhance our ability to assess the impact of micro- and nano-sized particles on processes taking place in agricultural and natural ecosystems by elucidating links between particulate (physical, biological and chemical) properties and their role in the sustainability and productivity of those systems. Research activities coordinated under this project will result in a catalog of physical and chemical properties of particulates related to agriculture production and of evaluations of the rate and transfer mechanisms of particulates through the environment. A greater number of scientists from state agricultural experiment stations will be utilizing the advanced analytical facilities funded by DOE and NSF to address important questions related to environmental protection and agricultural production. This will lead to the development of a better understanding of the behavior of pollutant and nutrient elements and compounds associated with fine particles in soil, water and air.

Related, Current and Previous Work

Members of this project are applying a wide range of analytical tools to elucidate mechanisms of physical and chemical protection of carbon and nitrogen in soils, colloid transport through soil, removal or sequestration of soil contaminants, climate change effects on soil structure, and deposition of synthetic nanoparticles on the human respiratory system. This project is unique as it combines the physical and chemical characterization of particles in water, air and soil using an array of modern analytical and modeling techniques. Other related multistate projects focusing on chemicals in air are more concerned with their geographical distribution and loads (NRSP003: The National Atmospheric Deposition Program-NADP). There is also a potential overlap with the activities of the project NCERA059 (Soil Organic Matter: Formation, Function and Management), but that group works mostly on biochemical and biological transformations of organic matter.

Several members of this group are working on various aspects of imaging and quantification of pore systems in soils, which is important for carbon sequestration as well as for transport of matter and chemicals through soil. Application of X-ray computed micro-tomography (Micro-CT) in soils is not trivial and requires development of specific procedures that account for differences in characteristics of soil particles as opposed to many other porous materials. Members of this group have significantly contributed to the development of several tools such as selection of proper image segmentation techniques to use in analysis of micro-tomographical images of intact soil particles (Wang et al., 2011); classification and characterization of soil micro-pores (Wang et al., 2012); comparison of selected imaging methods at varying resolutions including high resolution X-ray tomography and synchrotron microtomography (Udwatta et al., 2013); development of new experimental techniques enabling combining computed tomography with traditional chemical and biological measurements (Ananyeva et al., 2013; Kravchenko et al., 2013), including combining micro-tomography with experiments on analysis of micro-scale transport of soil microorganisms (Kravchenko et al., 2013; Wang et al., 2013). Current research includes 1) evaluation of soil pore continuity and tortuosity under different land management systems and climate scenarios, and 2) development of a new procedure for identifying particulate organic matter in intact soil samples using Micro-CT (Kravchenko et al., 2014). Proposed work in this area will expand on the current findings by studying relationships between placement of organic carbon and roots in relation to soil pores under various scenarios that include, among others, soil management and climate change, while continuing the development of tools that would allow the scientific community take full advantage of high resolution 3D imaging of soil pores.

Other members of this project are using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM) and energy dispersive X-ray (EDXA) to study colloid transport through soil, presence of nanoparticles in consumer products, and the study of organo-mineral associations in micro- and nano-environments. For the latter type of studies, one of the major challenges is a lack of non-invasive analytical tools that provide explicit information about the linkage between mineralogy and organic carbon functionalities, as well as the spatial allocations and other architectural features of organo-mineral assemblages. Scanning Transmission X-ray Microscopy (STXM), coupled with Near Edge X-ray Absorption Fine Structure Spectroscopy (NEXAFS) or X-ray Absorption Near Edge Spectroscopy (XANES), is a powerful technique to image nitrogen and carbon in their different forms at a nanometer spatial resolution (Chen et al., 2014 a, b; 2015). To manage and prevent particle detachment from agricultural and natural soils, or engineered media such as mine tailings, in-depth knowledge about prevailing physical processes that promote aggregation (e.g., pore topology and carbon and moisture distributions) is required. Utilizing synchrotron and other analytical systems to quantify pore geometries and carbon distributions of particulate matter will provide useful information for management decisions needed to reduce human and plant health risk.

Synchrotron-based spectroscopy has been used to study preferential accrual of peptides/proteins by soil minerals in undisturbed ecosystems of different ages (Xia, Kang – unpublished results). The result from this investigation strongly supports the hypothesis that peptide/protein-mineral interaction plays an important role in affecting the terrestrial N cycle. Intimate association of organic matter with mineral phases has been acknowledged as a fundamental mechanism for stabilizing organic compounds against biological degradation, and controlling the long-term sequestration of organic matter in terrestrial ecosystems. Understanding the dynamics of organic matter within the mineral matrix at the organo-mineral interface at the micro- and nano-scales is essential for understanding the processes controlling the quantity, quality and turnover of OM attached to mineral particles.

Investigations by members of this group are aimed at understanding physical, chemical and mineralogical mechanisms of carbon sequestration using synchrotron based STXM-NEXAFS, -XANES as well as traditional wet chemical analysis such as iron/aluminum fractionation techniques (Pitumpe Arachchige et al., 2012; 2013a; 2013b; 2014). Proposed work in this area includes submicron-level investigations of the compositional chemistry and interactions of various elements (Ca, Fe, Al and Si) present at the organo-mineral interface with organic carbon and organic carbon forms in soils under different land-uses (forest, agriculture and pasture) and varying redox conditions (upland versus wetland). Bulk techniques, including Fe K-edge EXAFS and Mössbauer spectroscopy and XRD, will be used to provide information on Fe speciation and soil mineralogy. Transport and retention colloids (nano- and micro-sized particles) in porous media through column breakthrough experiments have also been conducted by members of this group. The tools used in their studies include in-situ pore-scale together with microscopy (e.g., bright field microscope, TEM, SEM, atomic force microscope) and spectroscopy (e.g., dynamic light scattering). Results were explained using surface interaction energy theories (DLVO or extended DLVO), force and torque analyses, and flow hydrodynamics (Sang et al., 2013, Sang et al., 2014, Zevi et al., 2009, Zevi et al., 2012, Zhang et al., 2010a, Zhang et al., 2010b). These investigations have shown that the air-water-solid contact line is an important retention site in soils, in addition to the solid-water interface, the air-water interface, and the grain-grain contacts. The aggregation and transport of engineered nanoparticles, including fullerene, carbon nanotubes, and silver nanoparticles were also studied by members of this group (Bouchard et al., 2013, Bouchard et al., 2012, Isaacson et al., 2011, Wang et al., 2014a, Wang et al., 2014b, Zhang et al., 2012, Zhang et al., 2013). Additionally, work underway is aimed at investigating the mobility of natural micron- and nano-sized particles such as black carbon/biochar particles (Wang et al., 2013a, Wang et al., 2013b, Zhang et al., 2010b).

Some natural fine particles such as clay and black carbon particles have a strong affinity to a range of environmental toxins, making them the ideal vehicle for facilitated transport of contaminants that otherwise remain immobile in soils. This topic needs to be fully understood to better utilize carbonaceous sorbents as in-situ soil remediation agents. Proposed work includes the utilization of synchrotron-based spectroscopic instruments to further explore association of environmental contaminants with natural or anthropogenic fine particles, the interactions of the fine particles with environmental surfaces, and subsequently their mobility through the soil profile. Specifically, we plan to further examine the mobility of black carbon particles and the enhanced transport of associated contaminants such as pharmaceuticals in soil and water environments. We also plan to study the bioavailability of fine particles (e.g., engineered nanoparticles) to microbes and plants, as well as the effect of fine particles (e.g., clay and black carbon particles) on the bioavailability of other environmental toxins.

Members of this group have also been involved in studies on the fate and transport of antibiotics resulting from land application of animal waste, considering that they constitute a significant concern in agroecosystems and associated water resources. Past work has evaluated the effects of vegetative buffers on adsorption sites for antibiotics and the influence of these adsorption/desorption processes on transport (Chu et al., 2010; Chu et al., 2013). Proposed work will focus on these transport mechanisms for similar pollutants.

A major challenge for food security and environmental health, particularly water quality, is availability and fate of P. Phosphorus is a macro nutrient applied in fertilizers. Sources of P for fertilizer are limited, and costs of sourcing the raw material are predicted to increase. On the other hand, there are many surface waters plagued by excess nutrients that degrade water quality. Agricultural practices are a major source of nutrient leaching into surface waters, and thus better management strategies are required. In order to develop accurate P management tools, process-based modeling is required, which requires knowledge of P speciation in the soil. Phosphorus speciation changes depend on soil properties and management. While many studies have conducted research on P reactivity and speciation in model systems (Arai and Sparks, 2001; Goldberg and Sposito, 1984; Grossl and Inskeep, 1992) or made macroscopic observations of soil P availability (Gburek and Sharpley, 1998; Kleinman et al., 2004; Preedy et al., 2001; Turner et al., 2004; Westermann et al., 2001), there is a need to bridge the gap between molecular-level studies and P availability studies. There are new tools being developed that allow for P speciation in natural samples (e.g., Khatiwada et al., 2012; 2014; Liu, et al., 2014), which will facilitate investigation of P speciation in field-based trials. Investigators working in this project are conducting research to develop and test these tools for use on soils.

The goal of this project is to utilize and integrate modern analytical instruments and techniques to provide information on physical properties, chemical processes, and biological processes occurring in soil systems. This includes a) development of knowledge to improve application of synchrotron tools to assess complex matrices; b) development of data analysis methods; c) continued development of faster analysis methods that will allow us to do more comparative investigations of complex environments and automated in-situ instrumentation for field-based organic chemical composition measurements of particulate matter and semi-volatile gases; d) continued development of analytical and data analysis methods for C, N, P, Al, Ca, Fe, trace elements, and organic chemicals; e) education of participants and the wider community of agricultural researchers in the use and availability of these techniques and instruments; and f) interaction with national laboratory facilities at Argonne, Brookhaven, Stanford, Berkeley and Hanford to promote their use in the agricultural sciences and assist in the development and acquisition of equipment and expertise relevant to the agricultural science community. To achieve these goals, three objectives will be pursued.

Objectives

1. Characterize the physical, chemical, biological and morphological properties of particulate matter and their environmental, health and economic impacts over a wide range of spatial and temporal scales, including their potential effects on ecological sustainability, food and energy production, climate change, and air, water and soil quality.<p>
   
2. Upgrade the skills of project participants to do research in heterogeneous environmental systems at the micro- and nano-meter scale.<p>
   
3. Integrate modern analytical instruments (e.g., synchrotron-based spectroscopy, diffraction and fluorescence, scanning force methods, conventional and laser-based spectroscopy, chemical analysis, and microtomography) and other techniques, including molecular to macroscopic modeling and measuring approaches to promote their use in the agricultural sciences and assist in the development and acquisition of equipment and expertise relevant to the agricultural science community.<p>
   

Methods

Objective 1 Approach Environmental particles are characterized by physical heterogeneity and chemical complexity. To determine reaction processes of particulates, it is of crucial importance to study their physical properties such as shape, aspect ratio, or surface roughness and chemistry. High spatial resolution and chemical specificity is critical for understanding the biogeochemistry of, among others, key elements like iron, carbon and phosphorous. Tools that allow access to the nm-µm spatial scales are essential for obtaining interpretable results on sample heterogeneity and complexity. For example, the reactivity and bioavailability of iron is dictated by speciation. Donald Sparks, Daniel Strawn and Ganga Hettiarachchi are planning collaboration within this project to study carbon complexation mechanisms with iron-oxides and clay minerals as they impact carbon cycling in the soil environment. Direct measurement of speciation in bulk materials generally produces an average signal that is not decipherable. The large suite of nano-particulate mineral phases, complexes with natural organic matter, and associations with microbial biofilms are best assessed directly and individually through X-ray nano-probe or micro-probe measurements. An additional advantage of many modern instruments (e.g., synchrotron-based x-ray absorption instruments, electron microscopes, scanning force microscopes) is compatibility with samples in ambient conditions--liquid water and ambient or relevant pressure. Another line of research represented in this project is the analysis of pore systems from 3D images generated by X-ray computed micro-tomography (Micro-CT). Stephen Anderson and Daniel Giménez will collaborate to develop consistent methods of image analysis to help quantify soil pores and evaluate soil processes. Synchrotron-based techniques have emerged as powerful tools for determining the chemical speciation of a wide variety of toxic elements in moist soil samples, waste-forms, and biological specimens with little or no chemical pretreatment at detection limits and spatial resolutions that, on the average, exceed those of conventional methods by several orders-of-magnitude. At the same time, more conventional techniques have continued to improve in terms of resolution, sensitivity, and ability to perform under realistic conditions, such as those found in the vicinity of a plant root. By integrating a range of analytical methods (see Objective 3), we can study both the nature of particulate matter and its behavior under a variety of environmental conditions. Objective 2 Approach The past decade has witnessed significant advances in technologies related to spatially resolved X-ray spectroscopic techniques, both as a result of advances in X-ray optics, focusing devices, and detectors, and because of greater availability of high brilliance synchrotron facilities world-wide. This includes the Advanced Photon Source (APS) at the Argonne National Laboratory, the Advanced Light Source (ALS) in Berkeley CA, the updated Stanford Synchrotron Radiation Lightsource (SSRL), and the National Synchrotron Light Source II (NSLS-II) at the Brookhaven National Laboratory. The result is that spatially resolved synchrotron-based X-ray fluorescence (XRF), X-ray absorption near edge structure spectroscopy (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy have become mainstream techniques in a number of scientific disciplines and are providing molecular- level information not previously available using other techniques. While there exists a variety of micro-analytical techniques that have long been used in these disciplines, synchrotron-based spatially resolved X-ray fluorescence spectroscopy (XRF), XANES, EXAFS spectroscopy, and X-ray diffraction (XRD) are emerging as important methods that complement characterization by traditional techniques, as well as by other new methods, such as spatially resolved luminescence, FTIR, and Raman spectroscopy. The reasons for this are the elemental specificity, low detection limits, non-destructive nature of the measurement, the ability, in many instances, to examine samples non-destructively, and the ability to extract information on valence states and on specific bonding environments or molecular forms of target elements in complex matrices. X-ray fluorescence has been long used as a technique for determining elemental concentrations in a variety of matrices (Bertsch and Hunter 2001). Synchrotron-based XRF techniques have increased the detection resolution by several orders-of-magnitude over conventional XRF techniques, being in the 50-100 ng g-1 range for many elements at third generation synchrotron facilities. Additionally, the enhanced brilliance of modern synchrotron facilities and advances in focusing optics, allow for spatial resolution down to approximately 1 µm for hard X-rays (>3 keV). In the soft X-ray energy range (<1keV), new tools such as scanning transmission X-ray microscopy (STXM) at the ALS provide ~20 nm spatial resolution for imaging, elemental/chemical mapping, and spectroscopy. The ability to access both hard and soft X-rays allows the investigation of most important nutrient elements (P, S, B, N and C), as well as transition and heavier elements. Spatially resolved XRF imaging has become a critical complementary technique that is a prerequisite for conducting spatially resolved X-ray absorption spectroscopy (XAS) and XRD for samples with heterogeneous distributions of target elements. Because spatially resolved XRF is a relatively rapid method, it can be used to efficiently examine complex samples to determine if there is heterogeneous elemental distributions on a spatial scale that is resolvable by the technique. However, one of the greatest challenges for using spatially resolved micro-spectroscopy is sample preparation. A focus of this multi-state group will be to work collaboratively on developing a knowledge base on the sample preparation methods to avoid artifacts. For instance, Donald Sparks and other team members are planning a collaboration to determine ideal sample preparation of natural material such as soils for analysis at synchrotron facilities. It is now widely accepted that specific information on the composition, surface characteristics, and morphology of particulate matter is prerequisite to the development of a comprehensive understanding of toxic element and nutrient behavior in soils and sediments. For example, phosphorous interacts with oxide surfaces to form strong chemical complexes that may reduce its availability to plants or transport to ground and surface waters. On the other hand, colloidal transport by wind or water may hasten the mobility of phosphorous while removing it from a cropping system. The nature of not only the P-soil interaction, but also the nature of the particle itself and its susceptibility to movement must be determined. This cannot be done by any one instrument or investigator. We will apply a mixture of spectroscopic, computational, and analytical methods to particles in complex systems such as soils and sediments under environmentally relevant conditions. Members of this project (e.g., Spark, Strawn and Hettiarachchi) are planning the use of novel synchrotron-based X-ray absorption and X-ray fluorescence spectroscopy to speciate phosphorus in soils. While there is growth in the number of micro- and nano-probe instruments at synchrotron facilities worldwide, the scientific user base for these tools in earth and environmental science is under developed. Specifically, these types of instrument lines are frequently oversubscribed and it can be difficult to gain access. Due to the scarcity of instrument time, fully developed research programs where statistically responsible sampling can be employed are limited. An additional and more problematic issue for new synchrotron users is gaining the knowledge required to conduct high-quality measurements and analyze, interpret, and publish meaningful data. We will facilitate the transfer of synchrotron-radiation expertise to new instrument users, and play a key role in helping these tools fulfill their promise for high-quality, high-impact environmental research over the next decade. The role of this project on these activities is facilitated by current active involvement by members of this multistate project on research at synchrotron facilities at Brookhaven and Argonne National Laboratories and the Stanford Synchrotron Radiation Light Source. Donald Sparks also serves on the users' executive committee at the National Synchrotron Light Source at Brookhaven National Laboratory, which place the members of this project in an ideal position to promote and assist users. Objective 3 Approach Other advanced analytical techniques are also at available at national advanced analytical centers. The Environmental Molecular Science laboratory (EMSL) is a national scientific user facility at the Pacific Northwest National Laboratory that has a number of instruments that could be of use for the study of soils and sediments. This includes spatially resolved luminescence (FTIR, and Raman spectroscopy) and various electron spectroscopy techniques including HREELS and UHV surface chemistry. An NMR facility is available, which includes eleven NMR spectrometers, ranging from 300 MHz to 900 MHz with capabilities for high-field liquid-state, solid-state, and micro-imaging techniques. Washington State University has a faculty member Prof. Kerry Hipps--on the EMSL user committee and Harsh, who has served on this committee in the past, communicates regularly with him on needs for environmental research. The Molecular Science Computing Facility at EMSL is a unique facility equipped with a high-performance supercomputer, computational resources, and expert staff tailored to address computational challenges at multi-scales in the environmental sciences. Computational approaches in combination with experimental investigations make it possible to couple phenomena across scales (from molecular to ecosystem levels) to generate mechanistic understanding of complex interactions in the environment. At EMSL, for example, environmental computational modeling has been used to address complex environmental cleanup problems, to advance the understanding of aerosol chemistry, and to explore the environmental behavior and toxicity of nano particles (Bose et al, 2009; Wan et al., 2008; Hess et al., 2009). Specialized instrument facilities, funded by the National Science Foundation and located at universities around the country, also have instruments that can assist in meeting the objectives of NC-1187. Our members can help educate each other to become new users, and promote teaching of graduate students and educators in the application of modern instrumentation for characterization of particulate matter. This can be accomplished through seminars, symposia, books, cooperative proposals, and organized tours at national facilities. As discussed above, we will continue to interact with users groups and the administration of synchrotron and other major instrument facilities, such the EMSL to open them to our members and other researchers in the agricultural community. We have been successful with this in the past and will expand to facilities beyond the synchrotron sources. Management Plan: The members of this project will seek funding from the USDA Agriculture and Food Research Initiative Competitive Grants Program, National Science Foundation Geobiology, Hydrology, and Ecology Programs, the Department of Energy’s Environmental Remediation Sciences Program, and other funding sources for projects that will use national and university user facilities to accomplish tasks that require integration of multiple instrumentation. To facilitate cooperation among project participants we will organize annual meetings for sharing of ideas and research results. When possible, these meetings will be held on sites of advanced analytic facilities. Discussions with facility scientists and facility tours will be part of the meetings.

Measurement of Progress and Results

Outputs

• Publications in peer-reviewed and high-impact journals in the field of particulate science such as Environmental Science and Technology, Langmuir, Soil Science Society of America Journal (SSSAJ), Journal of Environmental Quality (JEQ), Geochimica Cosmochimica Acta, Journal of Geophysical Research, Atmospheric Chemistry and Physics, Proceedings of the National Academy of Sciences, Science and other relevant journals.<p>
• Presentations at national/international meetings: These include those of the American Chemical Society, American Geophysical Union, European Geophysical Union, American Society of Agronomy, Clay Minerals Society, American Association of Aerosol Research and other relevant meetings.<p>
• Proposals submitted to private, federal, and multinational funding sources: AFRI, DOE, EPA, NIHS, and NSF.<p>
• Annual meetings of NC1187 group that coordinate with tours of national user facilities, symposia at national society meetings, and conferences organized by NC1187 participants.<p>

Outcomes or Projected Impacts

• Generate new fundamental knowledge of the properties of micro-and nano-meter scale particles in air, soil, and water. We will examine particles and their spatial organization in agricultural systems that directly impact the availability of nutrients and water to living organisms. Microscopic and spectroscopic methods will be used to characterize the locations, bonding mechanisms, and concentrations of C, P, K, Fe, micronutrients, meta(loid)s and contaminant species associated with organic and inorganic particles and their aggregates.<p>
• Microscopic and molecular characterization of particles will be combined with macroscopic studies to link particle properties and those resulting from their spatial organization with environmental behavior. We will develop mechanistic models for the partitioning of material at interfaces to link micro- and nano-meter scale processes to mass transfer at larger scales. These models will be applied to environmental and agricultural systems, including interactions between minerals and plant roots, atmosphere and air-borne particles, sediment and water, and nanoparticles and microbial cells.<p>
• Increase the utilization of national laboratory supported advanced analytical techniques by agricultural scientists. Members will use their contacts and influence on user committees of national laboratories and other service centers to gain access to state-of-the-art instrumentation. In addition, they will inform other members of the availability and capabilities of instrumentation through seminars, email, and posts to the project homepage. Each member will work to educate and encourage colleagues and collaborators at their institutions in the use and means of accessing modern instrumentation, including synchrotron sources and national user facilities.<p>

Milestones

(2015): 1. Final Report Working Group formed to prepare report for previous project. 2. Participate in SSSA International Annual Meetings session entitled “Cutting Edge Methods for Determining Soil Chemical Species and Reaction Processes,” to showcase NC1187 accomplishments.

(2016): 1. Publish a Special Issue in a high impact journal such as SSSAJ or JEQ with selected articles from the session held the previous year. 2. Develop and Evaluate New and Existing Relations with User Facilities. Using the special relationship between NC1187 and national synchrotron facilities such as APS as a model, form similar bonds with national labs, including EMSL, the Advanced Light Source (Berkeley), the National Synchrotron Light Source (NSLS), Stanford Synchrotron Radiation Laboratory, and user facilities at universities.

(2017): 1. A Proposal Working Group formed to gather information on funding sources for particulate research that updates the membership and looks for opportunities for multi-investigator proposals using NC1187 membership. 2. Submission of Multi-Investigator Proposals to appropriate federal agencies. The proposal preparation will be coordinated by the Proposal Working Group.

(2018): Evaluate success of multi-investigator proposal submissions and if needed, adjust the proposal according to comment received from the reviewers.

(2019): 1. Prepare synthesis document of project accomplishments and future research needs. 2. Discuss potential for future Multistate project.

Projected Participation

View Appendix E: Participation

Outreach Plan

1. Continuation and expansion of relations with national user facilities including membership on user committees, submission of white papers on user facility needs for agriculture, and interaction with specific facility scientists to develop instruments and methods germane to agricultural research. 2. Develop complementary research methods to solve difficult problems in particulate matter characterization and behavior requiring multi-instrumental expertise and availability. To stimulate this outreach objective we will first develop the white paper on user facility needs and capabilities for agriculture. This will serve to focus member skills, interests, and needs. Step one of the white paper planning will be to organize a sub-committee to lead white paper development. The subcommittee will survey Group members on their advanced analytical needs for agricultural research. The white paper will be used as a directive when communicating Group activities and interests to funding agencies and synchrotron development groups. It will serve as an advocacy document that members can use when interacting with facility governing boards. This document will be posted on the Project Homepage. 3. Hold workshops, conferences, and short courses that educate agricultural scientists as to the availability, application, and use of modern instruments for particulate matter research. Members will present their research at professional society meetings to educate other scientists of the value and capabilities of advanced molecular scale facilities. Because most Group members have State Agricultural Experiment Station (AES) appointments, research that utilizes advanced analytical facilities will be reported to constituents (e.g., Ag-day), and AES members and administrators.

Organization/Governance

Governance of the multi-state project will lie with three elected positions: chair, vice-chair and secretary. Each position is assigned specific tasks and is held for two years with officers rotating through the positions as follows: the chair steps down, the vice-chair becomes chair, the secretary becomes vice-chair and a newly elected individual becomes secretary. Appointed last meeting: Daniel Gimenez (chair), Daniel Strawn (vice-chair), and Ganga Hettiarachchi (secretary). The chair is responsible for organizing the technical program for the upcoming "all hands" meeting. Each official group on the multi-state project is required to present a research report at each "all hands" meeting. If synchrotron funding is secured, each group allocated synchrotron time during a given year is required to attend the "all hands" meeting and present a research report. The research report will consist of an abstract and either an oral presentation or a poster presentation. If synchrotron funding is secured, the chair will be the official liaison with funding source(s) and synchrotron facilities. The vice-chair is responsible for organizing the logistics for the "all hands" meeting: selecting a venue, reserving rooms suitable for research presentations and the business meeting, arranging housing, etc. The secretary is responsible for all communication with official members of the multi-state project and, if synchrotron funding is secured, individuals allocated synchrotron time. The secretary is also responsible for preparing the annual report for the multi-state project, which will include the proceedings of the "all hands" meeting: minutes of the business meeting, the technical program, and the abstracts of all research reports. All members are responsible for creating links to user facilities and conveying information on availability and capabilities to the membership.

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Land Grant Participating States/Institutions

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Non Land Grant Participating States/Institutions