Brief Summary of Minutes of Annual Meeting

Thursday May 23, 2013 Introductions Welcome note from Dr. Nancy Cox about the agricultural systems in Kentucky. Welcome from Dr. Todd Pfeiffer, Department chair of Plant and Soil Sciences Ole Wendroth talked about the SSSA new mission and vision statement Dr. Josh Heitman, North Carolina State University, will be hosting the meeting next year Mandy Liesch will be the meeting secretary Kristofer R. Brye gave an overview of rice production with Arkansas and a review on the associated methane productions. Presentation was called Textural Effects on Methane Emissions from Direct-Seeded Delayed Rice Production (PhD student Chris W. Rodgers work). Silt loams begin methane emissions quicker and have higher overall season long emissions. Methane emissions are greater from soils with rice compared to those with bare soils. Organizational comments/break Yahannes Yimam gave a review of the soil physics group at Oklahoma State. Presentation was titled Two way interactions between bioenergy cropping systems and water resources. He is working with the water use efficiency of biofuel plants and their associated water balance. Springtime precipitation is very important to yield and water use efficiency. A drought can reduce WUE and total yield. Jason Warren talked about the variability in soil carbon stock measurements. This program is to help give farmers carbon credits and monitoring. Fixed mass method allows comparable results with other field results. He also said that bulk density may not be necessary in sampling, and the required number of samples with a detailed power analysis that may not be possible. A lot of discussion ensued about sampling and sampling procedures. Mandy Liesch presented on the development of an infiltration index for land use decisions in Urbanizing regions. Saturated hydraulic conductivity in the subsurface was the most important driving factor to hydrology in the region. Xinhua Xiao presented on Soil carbon dioxide fluxes with time and depth. Soil CO2 depths increased with soil depth and fluxes decreased with depth. Leaf area index, soil water, plant roots, and soil temperature were the main factors impacting CO2 concentration and fluxes. April Newman presented on the effect of sugarcane management in Louisiana. In general, the treatment with no burning had more carbon in the soil than the burned treatment. Sleem Kreba talked about the differences in CO2 flux in space and time. CO2 flux was higher in a grass system compared to a crop. Variability of CO2 flux was more pronounced in time than in space. Ole Wendroth talked about State Space analysis in soil physics. Why not implement spatial relationships in pedotranfer functions? State space models are efficient for detecting and describing spatial processes providing more useful information. It becomes more powerful with cross spectral analysis. Yang Yang talked about the space state approach to describe bromide leaching at a field scale. Soil Br at all depths has spatial correlation with depths. Discussion of the future of the Southern Regional Soil Physics/Carbon reform. What do we want to do to facilitate data centers. Kris Brye won the best presentation. On Friday, the group visited the Climate Change Research site of Dr. Rebecca McCulley and the Land Use Impact Study Site of the Soil Physics program.

Long-term tillage and residue management plots were established in 2003 at the Yucheng Comprehensive Experiment Station in the North China Plain by the USDA Sedimentation lab. The effects of different tillage-residue managements for a winter wheat and summer maize double-crop system on soil organic carbon (SOC) and total nitrogen (N) pools were determined. No-tillage with residue cover (NTR), no-tillage with residue removed and manure applied (NTRRM), and conventional tillage with residue removed (CTRR) were investigated for 6 years, based on a uniform N application among treatments. NTR and NTRRM sequestered more SOC in the surface (0-5cm) than CTR but for the whole soil profile (0-60 cm), NTRRM, NTR and CTRR sequestered SOC at the rates of 0.66, 0.27 and 2.24 Mg ha-1 yr-1. These long-term plots were warmed using infrared heaters to address the effects of global warming on carbon sequestration and crop growth. Warming increased the wheat aboveground biomass from 10%-20% suggesting the potential to sequester more CO2. Despite the lower SOC pool at the surface under CT, CO2 emissions were significantly (P<0.05) greater (by 11.7% on average) than under NT. Under the simulated global warming environment, responses of soil CO2 emissions decreased with time in CT while it consistently increased in NT system during the three wheat seasons and two maize seasons. Oklahoma State University has collected and pre-processed a large archive of soil samples from the stations of the Oklahoma Mesonet, a world class environmental monitoring network spanning the state of Oklahoma.

Hou, Ruixing, Zhu Ouyang, Yunsheng Li, D.D. Tyler, Fadong Li, G.V. Wilson. 2012. Effects of tillage and residue management on soil organic carbon in the North China plain. Soil Sci. Soc. Am. J., 76:230-240, doi:10.2136/sssaj2011.0107. Hou, Ruixing, Zhu Ouyang, Yusheng Li, and G.V. Wilson. 2012. Is the change of winter wheat yield under warming caused by shortened reproductive period? Ecology and Evolution, 2(12):2999-3008. DOI:10.1002/ece3.403. Hubbard, R.K., T.C. Strickland, and S. Phatak. 2013. Effects of cover crop systems on soil physical properties and carbon/nitrogen relationships in the coastal plain of southeastern USA. Soil & Tillage Research 126:276-283. Knoll, J.E., W.F. Anderson, R. Malik, R.K. Hubbard, and T.C. Strickland. 2013. Production of Napiergrass as a Bioenergy Feedstock Under Organic Versus Inorganic Fertilization in the Southeast USA. Bioenerg. Res. DOI 10.1007/s12155-013-9328-1 Krueger, E.S., T.E. Ochsner, J.M. Baker, P.M. Porter, and D.C. Reicosky. 2012. Ryecorn silage double-cropping reduces corn yield but improves environmental impacts. Agron. J. 104:888-896. Strickland, T.C., T.L. Potter, C.C. Truman, D.H. Franklin, D.D. Bosch, G.L. Hawkins. 2012. Results of rainfall simulation to estimate sediment-bound carbon and nitrogen loss from an Atlantic Coastal Plain (USA) ultisol. Soil & Tillage Research, 122:12-21