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ARS Home » Plains Area » Fort Collins, Colorado » Center for Agricultural Resources Research » Soil Management and Sugarbeet Research » Research » Research Project #432311

Research Project: Management Practices for Long Term Productivity of Great Plains Agriculture

Location: Soil Management and Sugarbeet Research

2021 Annual Report

Objective 1: Develop and refine management practices for enhanced yields, nitrogen use efficiencies, carbon sequestration, soil biodiversity and function, and reduced greenhouse gas emissions from agricultural systems of the Great Plains. Sub-objective 1.1: Improve nutrient (especially nitrogen) management. Sub-objective 1.2: Reduce greenhouse gas emissions (CO2, N2O, CH4). Sub-objective 1.3: Characterize soil C and N stocks, fractions, isotopic signatures, and SOC chemistry with depth to develop BMPs that increase C-Seq. Sub-objective 1.4: Evaluate the effect of management practices on soil microbial structure and function. Sub-objective 1.5: Increase long-term productivity and economic returns. Objective 2: Improve procedures for national agricultural greenhouse gas inventories and indices to assess soil biology, soil health, and nutrient management. Sub-objective 2.1: Develop a new USDA ARS Nutrient Uptake and Outcome (NUOnet) database and improve nutrient indices and tools. Sub-objective 2.2: Improve procedures and tools for assessment of greenhouse gas emissions (CO2, N2O, CH4), NUE and C-Seq. Sub-objective 2.3: Develop a new national soil biology database. Sub-objective 2.4: Develop a new soil biology (soil health) index to quantify beneficial bacteria in soil. Objective 3: Assess the long-term consequences of management practices and cropping systems on nitrogen use efficiencies, greenhouse gas emissions, carbon sequestration, soil biodiversity and functions. Sub-objective 3.1: Implement a data management plan and procedures to facilitate data archiving and retrieval in the national databases developed in Objective 2 (NUOnet, GRACEnet, soil biology). Sub-objective 3.2: Improve long-term nutrient (especially nitrogen) management, while reducing the long-term emissions of greenhouse gases (CO2, N2O, CH4), increasing C-Seq, and enhancing soil health.

Often the management of agricultural lands has led to degradation of the soil resource, including the depletion of soil carbon and the loss of natural and synthetic nutrients. The lost carbon and nutrients negatively impact producer’s profit margins and have negative environmental impacts (lead to increased buildup of greenhouse gases (GHG) in the atmosphere and pollution of surface and ground water resources). Improved agricultural management can reverse this degradation, improve profit margins and minimize or even mitigate the negative environmental impacts. The overall goal of this project is to develop new and/or improved best management practices (BMPs), new and/or improved models, tools and databases, and sustainable production systems that can help us adapt to and/or mitigate climate change. We will use a combined approach that incorporates field applied studies to develop BMPs (Objective 1); develop and/or improve models, databases, and analytical tools (Objective 2); and conduct field analysis of long-term patterns and processes to assess if the performance of the BMPs is maintained, or improved, over time, and if the models and/or other tools can simulate measured values over decades (Objective 3). The scientific approach includes using different key performance variables of plant productivity such as crop yields; and soil health, nitrogen use efficiency, greenhouse gas emissions, soil carbon sequestration, and soil biological structure and function. A full economic analysis of each BMP will also be conducted. Additionally, basic mechanistic research to increase our knowledge of the basic science and processes of soil chemistry, soil physics, and soil biology, is also being conducted. The Soil Management and Sugar Beet Research Unit scientists have unique skills in each of these fields, and also bring outside collaborators together as part of a comprehensive and multi-faceted research program. As a result of this research, new and viable solutions are developed that address the complexities associated with soil and air management. Tools and information are provided to producers, land managers, and policy makers helping to ensure productive and healthy soils, climate change mitigation and adaptation, and improved air and water quality. Farm sustainability and profitability are improved while improving conservation and minimizing negative environmental impact.

Progress Report
Objective 1. Studies about how management practices impact long-term agricultural productivity of the Great Plains continue. Studies on increasing the sustainability of these systems to sequester soil carbon, reduce greenhouse gas emissions, increase nitrogen use efficiencies and economic returns, prevent soil/water degradation, enhance yields, and maintain soil biology continue to be conducted. Various nitrogen management strategies related to the 4R (right time, source, type, rate) are being evaluated. The use of other best management strategies such as cover crops, crop residue management, and tillage practices that minimize soil disturbance is also being monitored. The development of alternative cropping systems as management practices (e.g., polycrops, sorghum sudangrass, and other rotations) is being assessed. These studies are providing information about how to improve long term management of cropping systems for increased sustainability, higher yields and higher nutrient use efficiencies. Objective 2. Carbon sequestration and greenhouse gas emissions studies continue: Database consolidation continues with increased data handling capacity, data visualization, on-the-fly-analysis, and site data uploads. Data from Greenhouse gas reduction through Agricultural Carbon Enhancement network (GRACEnet) and Nutrient Uptake and Outcome network (NUOnet) have been incorporated into Agricultural Collaborative Research Outcomes System (AgCROS), which also includes information from related ARS projects - Resilient Economic Agricultural Practices (REAP), Long Term Agroecosystem Research (LTAR), Agricultural Antibiotic Resistance (AgAR), and other networks. Publicly available GRACEnet data include crop yield, soil carbon, greenhouse gas (GHG) emission, land management, weather, and other information from 33 field sites across the U.S. with some studies beginning in the 1980s. In addition to observational data, the system now also generates maps of nitrous oxide (N2O) emissions based on the USDA GHG inventory for major crop types across the U.S. Long term harvested biomass, soil carbon stock, and nitrous oxide emissions data from studies in Colorado and other regions continue to be collected to improve and evaluate the DayCent (Daily CENTURY) model and perform meta-analyses. NUOnet datasets from 10 additional sites have been aligned, in addition to the previous 11 NUOnet field sites released in fiscal year 2019. DayCent was recently extended to simulate ammonia volatilization associated with application of urea-based fertilizers, slow-release nitrogen and fertilizers formulated with nitrification and urease inhibitors. Bayesian calibration is currently being used to parameterize and evaluate the new model against an extensive data set with high quality nitrous oxide measurements from the US and around the world. The enhanced model will be used to estimate soil greenhouse gas emissions reported in national inventories starting in 2022. Model input databases used for the inventory simulations have also been improved by combining land use/cover data from the National Resources Inventory (NRI) with more detailed Conservation Effects Assessment Project data. The improved database was used to extend model input files to 2015 and simulations were performed for the national GHG inventory published in 2021. The soil biology system (myPhyloDB) has been optimized to increase the speed for all data uploading and handling procedures. Several new univariate and multivariate analyses have also been added. Hundreds of soil samples from the USDA Natural Resources Conservation Service Soil Health Assessment Initiative have been received and have been analyzed for microbial community composition and beneficial gene abundance. These samples, in addition to nearly 1000 samples from ongoing research projects analyzed under this research project, are being used to develop indicator curves for selected beneficial genes (e.g., nitrogen fixation) and a general molecular assessment of soil health. Objective 3. Long-term studies were monitored at Colorado State University. Field sampling of nitrogen fertilization, no-tillage, and organic matter addition studies was completed for the 2019 field year, and laboratory analyses are in progress. Long-term data analyses are in progress. It was found that when deep soil carbon under long-term no-tillage was compared to strip tillage, although strip tillage improved yield by 13%, soil carbon was lost, even with low-impact tillage. Laboratory analyses for field sampling of nitrogen fertilization, no-tillage, and organic matter addition studies are underway. Data analysis continues on the impact of residue removal on soil microbial communities and soil carbon fractions. Studies on the long-term effects on soil biological diversity and function, greenhouse gas emissions, carbon sequestration, nitrogen use efficiencies, and macro- and micro-nutrient dynamics are being conducted. Long-term studies found that manure applications increased crop quality compared to inorganic nitrogen fertilizer application. Manure increased grain concentrations of nutrients such as nitrogen, phosphorous, potassium and magnesium, which are important elements in animal nutrition. These studies found that management practices that maintain or improve soil health and nutrient availability also improve maize productivity and nutritional quality, which could have cascading positive impacts on animal and human nutrition. The studies show that conservation agriculture practices are good alternatives to traditional practices to increase the sustainability of these irrigated farming systems.

1. Molecular indicators of soil biology serve as a scientific foundation for soil health determination. Soil health serves as the foundation for modern conservation strategies, but objective measures of what constitutes soil health have been lacking. To enable objective assessment of the microbial contributions to soil health, ARS researchers in Fort Collins, Colorado, developed molecular indicators of soil biological community structure and function. These methods have been accepted as standards by the Soil Science Society of America and are used by the USDA-Natural Resources Conservation Service (NRCS) in its conservation planning and implementation mandate.

2. Limited irrigation can be a key water conservation and carbon sequestration strategy in the Western United States. Limited irrigation, in which less than the ideal amount of irrigation water is applied to a crop, can be a key water conservation strategy and carbon sequestration tool in western agricultural systems where water is scarce. ARS researchers in Fort Collins, Colorado, along with collaborators from Colorado State University, employed a variety of state-of-the-art techniques to determine where carbon is stored in soils under limited irrigation management. The insights gained in this research provide valuable information to best manage limited irrigation to improve carbon sequestration and thus soil health. The dual benefits of this research, that is conserving water and sequestering carbon, will be increasingly vital in developing sustainable agricultural systems in the arid Western United States.

Review Publications
Follett, R.F., Stewart, C.E., Bradford, J.A., Pruessner, E.G., Sims, P.L., Vigil, M.F. 2020. Stable C isotope data of southern mixed-grass prairie vegetation from Oklahoma, United States. Data in Brief. 32.
Delgado, J.A., Gantzer, C.J., Sassenrath, G.F. 2020. Soil and water conservation: A celebration of 75 years. Ankeny, IA: Soil and Water Conservation Society. 331 p.
Delgado, J.A., Barrera Mosquera, V.H., Alwang, J.R., Villacís Aveiga, A., Cartagena Ayala, Y.E., Neer, D.L., Monar, C., Escudero López, L.O. 2020. Potential use of cover crops for soil and water conservation, nutrient management, and climate change adaptation across the tropics. Advances in Agronomy. 165:175-247.
Villacis, A.H., Ramsey, F.A., Delgado, J.A., Alwang, J.R. 2020. Estimating economically optimal levels of nitrogen fertilizer in no-tillage continuous corn. Journal of Agricultural and Applied Economics. 52(4):613-623.
Wang, Y., Dou, F., Paustian, K., Del Grosso, S.J., Storlien, J., Wight, J., Hons, F. 2020. Simulating impacts of nitrogen fertilization using DAYCENT to optimize economic returns and environmental services from bioenergy sorghum production. Agronomy Journal. 112:4861-4878.
Delgado, J.A. 2020. Water Quality. In: Delgado, J.A., Gantzer, C.J., Sassenrath, G.F., editors. Soil and Water Conservation: A Celebration of 75 Years. Ankeny, IA: Soil and Water Conservation Society. p. 123-139.
Delgado, J.A., Gantzer, C.J., Sassenrath, G.F. 2020. The future of soil, water, and air conservation. In: Delgado, J.A., Gantzer, C.J., Sassenrath, G.F., editors. Soil and Water Conservation: A Celebration of 75 Years. Ankeny, IA: Soil and Water Conservation Society. p. 307-331.
Barrera, V., Delgado, J.A., Alwang, J., Escudero, L., Arévalo, J., Cartagena, Y. 2020. Prácticas de agricultura de conservación promueven la productividad y sostenibilidad del sistema de producción papa-pastos en la microcuenca del río Illangama, Ecuador. Agricultural Research Service Station Bulletin. 448:10-38.
Sanderman, J., Savage, K., Dangal, S.R., Duran, G., Rivard, C., Cavigelli, M.A., Gollany, H.T., Jin, V.L., Liebig, M.A., Omondi, E.C., Rui, Y., Stewart, C. 2021. Can agricultural management induced changes in soil organic carbon be detected using mid-infrared spectroscopy? Remote Sensing. 13(12). Article 2265.
Rocci, K., Lavelle, J., Stewart, C.E., Cotrufo, F. 2021. Soil organic carbon response to global environmental change depends on its distribution between mineral-associated and particulate organic matter: A meta-analysis. Science of the Total Environment. 793. Article e148569.
Parton, W.J., Del Grosso, S.J., Campbell, E.E., Hartman, M.D., Hobbs, N.T., Moore, J.C., Swift, D.M., Schimel, D.S., Ojima, D.S., Coughenour, M., Boone, R.B., Paustian, K., Hunt, H.W., Woodmansee, R.G. 2021. Five decades of modeling supporting the systems ecology paradigm. In: Woodmansee, R.G., Moore, J.C., Ojima, D.S., Richards, L., editors. Natural Resource Management Reimagined: Using the Systems Ecology Paradigm. Cambridge: Cambridge University Press. p. 90-130.
Kanter, D., Del Grosso, S.J., Scheer, C., Pelster, D., Galloway, J. 2020. Why future nitrogen research needs the social sciences. Current Opinion in Environmental Sustainability. 47:54-60.
Gollany, H.T., Del Grosso, S.J., Dell, C.J., Adler, P.R., Polumsky, R.W. 2021. Assessing the effectiveness of agricultural conservation practices in maintaining soil organic carbon under contrasting agroecosystems and a changing climate. Soil Science Society of America Journal. 85(5):1362-1379.
Hartman, M.D., Parton, W.J., Derner, J.D., Schulte, D., Smith, W.K., Peck, D.E., Day, K.A., Del Grosso, S.J., Lutz, S., Fuchs, B., Chen, M., Gao, W. 2020. Seasonal grassland productivity forecast for the U.S. Great Plains using Grass-Cast. Ecosphere. 11(11). Article e03280.
Gurung, R., Ogle, S., Williams, S., Breidt, J., Zhang, Y., Del Grosso, S.J., Parton, W., Paustian, K. 2021. Modeling ammonia volatilization from urea applied to agricultural soils in the DayCent model. Nutrient Cycling in Agroecosystems. 119:259-273.
Da Silva Ledo, A., Do Amaral, A., Jenderek, M.M., Harrison, M.L., Manter, D.K. 2020. Sterilization procedures and Plant Preservative Mixture on in vitro establishment of Miscanthus sinensis Anderson. Plant Cell Culture & Micropropagation. 15(2):27-32.
Leichty, S., Cotrufo, M.F., Stewart, C.E. 2020. Less efficient residue-derived soil organic carbon formation under no-till irrigated corn. Soil Science Society of America Journal. 84(6):1928-1942.