Location: Soil Management and Sugarbeet Research
2022 Annual Report
Objectives
1. Evaluate the influence of conservation practices (e.g., tillage, cover crops, and soil amendments) on C and nutrient cycling through the soil profile to inform management and cropping system practices regarding optimization of C and nutrient cycling for increased productivity, sustainability, and ecosystem services.
o Sub-Objectives 1.A-1.D can be found in uploaded post plan in Related Docs.
2. Investigate the effects of integrating multiple conservation practices (e.g., tillage, cover crops) on crop productivity and soil health to provide information and support development of tools to producers and managers in response to conservation practice adoption.
o Sub-Objectives 2.A and 2.B can be found in uploaded post plan in Related Docs.
3. Evaluate the long-term ecosystem benefits of conservation practices resilient to climatic variation to provide data and tools to producers and farm managers for assessing best conservation practices.
o Sub-Objectives 3.A-3.C can be found in uploaded post plan in Related Docs.
Approach
Soil function is an interplay of physical, chemical, and biological processes, and soil microbes play a direct role in driving soil chemical and physical processes important for overall ecosystem function. There remains, however, substantial uncertainty regarding how critical factors such as the soil’s microbiome, variabilities in nutrient cycling, management strategies, and variabilities in environment and/or climate change all interact to determine agricultural productivity and environmental outcomes. This project utilizes a holistic systems approach to develop new Best Management Practices and understanding of the interactive nature and interdependence of the Genetics x Environment x Management (GxExM) factors that result in highly productive and resilient agricultural systems. The objectives of this research are designed to integrate the scientists’ expertise related to soil function, crop productivity, and ecosystem services; each scientist is an expert in his/her field and responsible for the measurement of performance variables including, but not limited to, nutrient cycling, GHG monitoring and modeling, soil C sequestration and cycling, and soil biology structure and function. The knowledge and outcomes of this work will contribute to increased yield and profit sustainability for farmers; protection of ecosystems; increased nutrient use efficiency (NUE) and reduced losses of N from of N input application; and improved understanding of N cycling in cropping systems. Additionally, this research will increase C sequestration (C-Seq), reduce greenhouse gas (GHG) emissions, enhance soil quality/soil health, and increase resilience to climate change. These studies will contribute to improved agricultural production supported by a deeper understanding of soil biological processes; they will also contribute to improved soil biological properties and functions and to the development of sustainable agricultural systems in the Great Plains.
Progress Report
Objective 1. Sub-objective 1.A: Evaluate the seasonal dynamics in soil parameters (e.g., microbial biomass and water-soluble Carbon (C) and Nitrogen (N)) in conventional and no-tillage continuous corn. Two-years of samples were collected up to twice per week during the growing season and twice per month during the off-season for a total of 66 sample dates. All laboratory analyses of living microbial biomass, soil C/N contents, water soluble C/N, and soil greenhouse gas (GHG) emissions have been analyzed and a preliminary model predicting microbial biomass has been developed. Sub-objective 1.B: Evaluate soil amendments, bio-stimulants, and enhanced efficiency fertilizers to reduce direct and indirect N loses to the environment promoting nutrient-use-efficiency, crop productivity, and yield. A greenhouse study examining the impact of enhance efficiency N fertilizer on plant biomass and soil microbial community structure and function has been completed and data analyses continue. Field plots have been installed at Colorado State University’s Agricultural Research, Development and Education Center (ARDEC) and sampling protocols and measurements are currently being developed. Novel formulations of biodegradable enhanced efficiency fertilizers continue to be tested in the laboratory for their ability to release N. Sub-objective 1.C: Evaluate cover crops to promote soil health, stress tolerance, and crop productivity. Field sampling and analyses have been conducted from two cover crop trials in collaboration with Natural Resource Conservation Service (NRCS) Plant Material Center locations in Oregon and Kansas. Plots have been installed at ARDEC to examine the ability of cover crops to improve yields in N and water limited forage production systems. Sub-objective 1.D: Track the impact of residue placement on soil organic C stabilization and loss using d13C to quantify carbon dioxide (CO2) efflux, incorporation into microbial biomass, and soil C fractions. Samples have been collected and laboratory analyses are in progress.
Objective 2. Sub-objective 2.A: Evaluate the effect of conservation practice stacking on ecosystem benefits (e.g., N losses, C/N storage and cycling, GHG reduction potentials), soil health (e.g., microbial biomass and molecular indicators of beneficial bacteria), and crop yield. Plots have been installed at ARDEC and sampling protocols and measurements are currently being deployed. Sub-objective 2.B: Continued refinement and development of models, indices, and decision support tools that evaluate the effect of conservation practices on ecosystem benefits, soil health, and crop productivity. On-going studies at ARDEC and world-wide continue to be used in the development and expansion of N tools such as a new Nitrogen Index for assessment of the effects of N management on the risk of N losses and potential impacts to soil health. An improved version of DayCent continues to be developed that includes an improved model of microbial biomass, testing and model validation with new datasets, and efforts to reduce model input burdens.
Objective 3: Sub-objective 3.A: Long-term studies continue at ARDEC evaluating N fertilization rates under tillage management, residue removal, and organic vs. inorganic N sources. A new study at ARDEC has been initiated to explore the impact of conservation practice stacking (i.e., tillage and cover crops) on resilience and/or resistance of yield, productivity, and ecosystem benefits to climate variability. Sub-objective 3.B: Enhance data stewardship and tech-transfer through improved databases, such as the Agricultural Collaborative Research Outcomes System (AgCROS). New data coordination, meta-data and data-sharing platforms and file formats are being developed for handling in-house and collaborative long-term research studies. Sub-objective 3.C: Develop, test, and refine standardized procedures for all phases of soil biological analyses, such as sampling collecting and handling, analytical techniques, and data storage and analyses. A standardized protocol cross-laboratory comparison of molecular analysis for soil microbial community composition has been developed and five different ARS laboratories have successfully analyzed a common set of soil samples to explore sources of variation and the repeatability of analyses conducted in different laboratories.
Accomplishments
1. Recovering manure's fertilizer value for a secure U.S. agriculture. Unprecedented fertilizer costs are exacerbating food prices and concerns over food security. The USDA "Manureshed" management research program develops innovative systems to recycle fertilizer nutrients between the nation's animal and crop production systems; thereby, turning a potential waste byproduct from a liability to animal producers into a beneficial resource for crop producers. Led by ARS scientists in USDA's Long Term Agroecoystem Research Network, this comprehensive research program takes advantage of USDA's extensive data systems, stakeholder networks, and innovative technologies to identify and promote opportunities for manure nutrient recycling across agricultural supply chains. Their results have identified opportunities to improve the use of manure fertilizer across much of the U.S.
Review Publications
Kleinman, P.J., Spiegal, S.A., Silviera, M., Baker, J.M., Dell, C.J., Bittman, S., Cibin, R., Vadas, P.A., Buser, M.D., Tsegaye, T.D. 2022. Envisioning the manureshed: Towards comprehensive integration of modern crop and animal production. Journal of Environmental Quality. 51(4):481-493. https://doi.org/10.1002/jeq2.20382.
Meredith, G., Spiegal, S.A., Kleinman, P.J., Harmel, R.D. 2022. The social networks of manureshed management. Journal of Environmental Quality. 51(4):566-579. https://doi.org/10.1002/jeq2.20334.
Dell, C.J., Baker, J.M., Spiegal, S.A., Porter, S.A., Leytem, A.B., Flynn, K.C., Rotz, C.A., Bjorneberg, D.L., Bryant, R.B., Hagevoort, R., Williamson, J., Slaughter, A.L., Kleinman, P.J. 2022. Challenges and opportunities for manureshed management across U.S. dairy systems: Case studies from four regions. Journal of Environmental Quality. 54(4):521-539. https://doi.org/10.1002/jeq2.20341.
