Location:2011 Annual Report
1a. Objectives (from AD-416)
1. Improve databases and provide other information on the soil C stocks, C-sequestration, and greenhouse gas (GHG) emission and fluxes of current and/or new soil management and cropping systems by use of measurement and/or model based approaches. 2. Develop sustainable biofuel production systems and practices that result in improved soil C sequestration, efficient use and recycling of applied nutrients (especially N), and minimal GHG emissions. 3. Characterize and measure the influences and processes of environmental and plant-related controls on C and N cycling and storage in soils. 4. Develop processes, primarily microbiological, that 1) minimize soil-borne disease thereby maintaining soil ecosystems and crop productivity, 2) enhance biofuel production, and 3) remediate damaged, and protect undamaged, soil and water. 5. Develop management practices and decision support tools that improve nutrient use efficiency and reduce losses in agricultural systems.
1b. Approach (from AD-416)
This research addresses priority science questions in the strategic plan for the Climate Change, Soils and Emissions Research (NP212) and provides a scientific foundation for decision-making and policy development. The five objectives in this project integrate studies focusing on effects of management practices on soil processes and sustainable crop growth and yield. Objective 1 addresses the need for improved databases and provides other information on the soil C stocks, C sequestration, and GHG emission and fluxes of current and new soil management and cropping systems. These data bases will be used to improve models and decision support systems. Objective 2 studies address sustainable biofuel and irrigated conservation tillage production systems and practices to improve soil C sequestration, efficient use and recycling of applied nutrients (especially N), and minimize GHG emissions. Objective 3 studies focus on characterizing and measuring the influences and processes of environmental and plant-related controls on C and N cycling, pool dynamics, and storage in soils. Objective 4 examines soil productivit and remediation tools that reduce soil-borne diseases and protect soils and soil waters from damage from soil contaminants. The goal is to utilize microbial isolates and communities for bioenergy production, biocontrol of soil-borne pathogens, and to remediate damaged soils. Objective 5 studies focus on improving nutrient use efficiency, especially N, and developing more advanced decision support tools (e.g., indices and models) for improved nutrient management. The overall SPNR research focus is on biological processes and management practices that influence SOC, GHG emissions, microbial and rhizosphere biology, pesticide/nutrient/contaminant removal from soil, bioenergy production, and nutrient use efficiency. All of these research projects share the common goal of improving or maintaining farm profitability while practicing sustainable and environmentally friendly agriculture.
3. Progress Report
Objective 1: Improved databases are required to assess land uses to reduce greenhouse gas (GHG) emissions. A web based database with GHG flux data is a product of GRACEnet. The software and a protocol is developed using actual GRACEnet data. Released the U.S. Agriculture and Forestry Greenhouse Gas Inventory. Objective 2: Impacts of biofuel using DayCent were done at scales us to river basin size. Field and laboratory work were completed as scheduled, and manuscripts prepared and published on effects of N fertilizer on grain and residue yields, and impact on soil C and N under plow tillage and no-till. Manuscripts published on N source and nitrous oxide emissions under irrigated, no-till corn and on measuring ammonia loss in small plots. Objective 3: Soil carbon sequestration was found to be underestimated for maize and switchgrass grown for bioenergy. Underestimation was by 60-100 percent when soils depths of 30-100 cm depths included rather than only to 30 cm as done previously. Manuscript submitted. The dynamics of soil C and soil N, although related, are not identical, thus soil C or N cycling can be targeted by management to improve ecosystem functioning and maintain soil organic matter dynamics to help minimize impacts of greenhouse gases on global change. Manuscript accepted. Objective 4. Shallow vadose zone biobarriers remove nitrate from percolating water. A pilot scale biobarrier is designed and installed to intercept runoff from a cattle pen. Aerobic and anaerobic biobarrier to remediate sulfacholorpyridazine contaminated groundwaters completed. Investigation of selenium movement through soils was complete. Microbial fuel cell study published. Samples collected for microbial diversity from a potato field trial in southern CO. Nearly 2000 bacterial isolates have been collected and isolates are being screened for bioactivity against Phytophthora spp. and for lignin degradation activity. A novel lignin degrading isolate has been identified and is appropriate culture collection. Objective 5: Ho 5.1a: All planned field and laboratory work completed as scheduled. Another year of field work was started in FY2011 for the needed observations to complete the studies field phase. A manuscript was accepted for publication on cooperative N management work with CSU at Rocky Ford, CO. Nitrogen losses from agricultural systems impact environmental and new tools are needed to help assess these losses. New USDA-ARS tools include the Nitrogen Trading Tool, Nitrogen Index 4.3, and NLEAP-GIS 4.2, now all calibrated and validated, and released via the ARS webpage (http://www.ars.usda.gov/npa/spnr/nitrogentools). These tools have been extensively downloaded for use both nationally and internationally to improve practices to decrease nitrogen losses to the environment.
Dabney, S.M., Meisinger, J.J., Schomberg, H.H., Liebig, M.A., Kaspar, T.C., Delgado, J.A., Mitchell, J., Reeves, D.W. 2010. Using cover crops and cropping systems for nitrogen management. p. 230-281. In Delgado, J.A. and R.F. Follett (eds) Advances in Nitrogen Management for Water Quality, Ankeny, IA.