2010 Annual Report
1a.Objectives (from AD-416)
The overall goal of this project is to develop soil and crop management systems that integrate biological, chemical, and physical principles to sustain agricultural production and environmental quality in the northern Great Plains. The project includes an investigation of the effects of management practices on soil biological, physical, and chemical properties; this information will be integrated with an assessment of one approach to restore eroded soil resources to indicate land management practices that may enhance long-term soil productivity, farm profitability, and environmental benefits in the northern Corn Belt. Specific objectives are to (a) determine the impact of management strategies on nutrient, soil carbon, and organic matter dynamics; and (b) to evaluate the impact of landscape restoration (soil movement from areas of soil deposition to areas of topsoil depletion) on soil properties, soil productivity, and environmental quality in severely eroded undulating landscapes.
1b.Approach (from AD-416)
Field experiments will be conducted in several sets of long-term research plots established by the North Central Soil Conservation Research Laboratory staff, including field plots implementing organic and conventional management practices that were established in 2002. The effect of organic and conventional land management practices on the structure of the soil biological community will be assessed in these plots through microbial biomass carbon and nitrogen and fatty acid methyl ester (FAME) profiles. The effect of nitrogen management practices on nitrogen availability will be evaluated by monitoring nitrogen mineralization. In separate field experiments, the soil and economic impacts of integrating corn stover harvest (for biofuel) into corn-soybean rotations will be evaluated by monitoring changes in soil properties and economic yield at different corn stover removal rates. Additional field experiments will be conducted to examine the effect of the timing and intensity of tillage, crop rotation, and planting date on carbon storage, crop growth, and economic yield. A five-year on-farm experiment will be conducted to evaluate the impact of landscape restoration by assessing (a) changes in soil chemical and physical properties (as a function of depth and landscape position) and topography that occur as a result of landscape restoration, (b) the productivity of restored and unrestored landscapes as a function of landscape position, (c) the economic costs and benefits of landscape restoration, (d) pesticide sorption and transformation in soils (as a function of landscape position and depth) in restored and unrestored landscapes, (e) the dynamics of soil biota (microarthropods) before and after soil movement for landscape restoration; and (f) the impact of landscape restoration and subsequent tillage on future soil erosion by tillage and water (using a predictive model).
This is the final report for the project 3645-12610-001-00D, which terminated March 2010. Field experiments for the 2009 growing season were completed and samples were processed and analyzed between the end of FY09 and the termination of the project. Unfinished components of the project were integrated into the new in-house project 3645-11610-001-00D and project 3645-61660-002-00D.
Significant progress was achieved during the life of this project. Field and laboratory experiments, as well as analysis of published empirical information, were conducted to quantify changes in soil properties brought about by harvesting corn stover for biofuel production. Information on the importance of non-grain crop biomass in maintaining soil quality and agricultural productivity was presented in the context of harvesting biomass for bioenergy at numerous national and international meetings. Research to determine crop residue needs to protect soil resources and identify management strategies that enable sustainable production of food, feed, and biofuel are an important component of the new project 3645-11610-001-00D.
Research was completed that demonstrated that no-till and strip tillage can increase profitability while protecting soil resources. Field experiments were conducted to determine the similarities and differences in soil microbial dynamics under conventional and organic cropping management practices, and to evaluate the impact of inorganic versus manure nitrogen management on nitrogen availability to crops. Preliminary results show no difference in nitrogen availability in crops fertilized with manure and conventional fertilizers. Objectives relating to nutrient dynamics are being continued as part of project 3645-61660-002-00D.
On-farm experiments were conducted to evaluate changes in soil properties and productivity in eroded soils. Studies were initiated to quantify short-term erosion impacts on soil carbon dynamics. Research was conducted in collaboration with farmers to determine weed dynamics and crop emergence, development, and yield response to variable soil properties at two soil-landscape rehabilitation sites. Results of these studies were transferred to growers, crop consultants, scientists, and others through publication in the peer-reviewed literature and through presentations at field days and other venues. This research is being continued and expanded as part of project 3645-11610-001-00D.
Numerous field and laboratory studies were completed to determine the environmental fate of pesticides in the soil-air-water system. Research was conducted to evaluate pesticide effectiveness, plant uptake, binding to soil, movement with water, and transformation in soil. Information regarding pesticide fate was transferred to other scientists, regulatory agencies, growers, crop consultants, and others through publication in peer-reviewed journals and presentations at field days, conferences, and workshops.
Soil processes should be considered in residue harvest management. Finite oil reserves, rapidly rising energy costs and increasing knowledge and concern about global climate change are driving changes in energy form and use. Non-food plant materials, including crop straws, corn cobs, grasses such as switchgrass, and trees, are being touted as sources of renewable energy. ARS researchers in Morris, MN led a national effort to summarize the risks of harvesting non-food plant material on critical soil processes and present management options that can prevent or minimize environmental risks. This information will educate scientists, industry, producers, policy-makers, and the general public of the benefits and risks associated with plant based energy.
Replacing translocated topsoil can restore productivity to eroded soil. The USDA Economic Research Service has determined that productivity losses due to erosion exceed $100 per square mile each year throughout most of the Corn Belt. Restoring topsoil to eroded land is critical to ensure adequate food production and to protect environmental quality. ARS researchers in Morris, MN are leading an international research team that is evaluating soil-landscape rehabilitation (moving soil from areas of topsoil accumulation to areas of topsoil depletion) as a means to increase the productivity of eroded land. Results from the first four years show that addition of accumulated topsoil from lower slope positions to eroded upper slope positions can improve soil quality in upper slope positions, resulting in yield increases of 11 to 48% in areas of soil addition and more consistency in crop yields across the landscape. This research indicates that soil-landscape rehabilitation may be a feasible approach to increase the productivity of eroded soils. Extension personnel, growers, crop consultants, and other scientists can use this information to better predict crop yield responses to soil properties and landscape position in eroded areas, to develop approaches to increase the productivity of eroded soils, and to recommend methods to remediate or restore eroded landscapes.
Johnson, J.M., Papiernik, S.K., Mikha, M.M., Spokas, K.A., Tomer, M.D., Weyers, S.L. 2009. Soil Processes and Residue Harvest Management. In: Lal, R., Stewart, B.A., editors. Soil Quality and Biofuel Production. Advances in Soil Science. Boca Raton, FL: CRC Press. p. 1-44.
Papiernik, S.K., Koskinen, W.C., Yates, S.R. 2009. Solute Transport in Eroded and Rehabilitated Prairie Landforms. 1. Nonreactive Solute. Journal of Agricultural and Food Chemistry. 57:7427-7433.
Papiernik, S.K., Koskinen, W.C., Yates, S.R. 2009. Solute Transport in Eroded and Rehabilitated Prairie Landforms. 2. Reactive Solute. Journal of Agricultural and Food Chemistry. 57:7434-7439.
Spokas, K.A., Baker, J.M., Reicosky, D. 2010. Ethylene: Potential Key for Biochar Amendment Impacts. Plant and Soil Journal. 333:443-452.
Ibekwe, A.M., Grieve, C.M., Papiernik, S.K., Yang, C.H. 2009. Persistence of Escherichia coli 0157:H7 on the Rhizosphere and Phyllosphere of lettuce. Letters in Applied Microbiology. 49:784-790.
Ibekwe, A.M., Papiernik, S.K., Yang, C. 2010. Influence of Soil Fumigation by Methyl Bromide and Methyl Iodide on Rhizosphere and Phyllosphere Microbial Community Structure. Journal of Environmental Science and Health. 45(5):427-436.