Performing Department
(N/A)
Non Technical Summary
With the continued need to satisfy the growing demand for agricultural products, ensuring the sustainability of food production systems while minimizing negative impacts on the environment has become a major challenge in the U.S. Corn Belt. Agricultural producers and conservation and watershed planners need to know what benefits we can achieve from implementing conservation practices so the USDA created the Conservation Effects Assessment Project (CEAP) to measure the effects of agricultural conservation practices. However, current watershed-scale efforts mainly focus on assessing the effects of conservation practices on water quality, while GHG emissions are not well considered. Furthermore, as the main watershed-scale water quality assessment tool utilized by the CEAP, the SWAT model lacks the capability of simulating soil C/N coupled dynamics as well as GHG production and emission processes. Therefore, the overall goal of this study is to develop a modeling framework (SWAT-DNDC) by incorporating algorithms from DNDC to enhance SWAT's capability of simulating C/N cycling processes, and GHG fluxes, to systematically evaluate the impacts of conservation practices on crop yield, water quality, and GHG emissions in the Corn Belt. We will leverage existing in situ observations, new field experiments, compiled regional-scale geospatial datasets, and in-stream hydrologic and water quality data from multiple sources to test SWAT-DNDC from site scale to CEAP watershed scale. We will perform scenario simulations of alternative conservation practices and climate change impacts in the Upper Mississippi River Basin (UMRB) to inform best management practices for crop production, water quality, and GHG emissions in the Corn Belt.
Animal Health Component
0%
Research Effort Categories
Basic
20%
Applied
30%
Developmental
50%
Goals / Objectives
The overall goal of the proposed research is to develop a modeling framework (SWAT-DNDC) to systematically evaluate the impacts of conservation practices on crop yield, water quality, and GHG emissions in the U.S. Corn Belt.
Project Methods
Our approach integrates in situ observations, DNDC, and the revised SWAT model to develop the SWAT-DNDC modeling framework aiming to evaluate the impacts of conservation practices on crop production, water quality, and GHG emissions in the Corn Belt. We will leverage existing observations, new field experiments, compiled regional-scale geospatial datasets (including management records, land use, soils, climate forcing, and hydrography), and in-stream hydrologic and water quality data from multiple sources. The rich datasets are valuable for verifying the credibility of SWAT-DNDC at site and watershed or regional scales. The new model development efforts and field experiments with high temporal resolution N2O flux measurement that will be conducted within the project scope include:1. Improve soil C and N cycling processes in SWAT-DNDC to accurately represent decomposition and C and N dynamics in agroecosystems.2. Incorporate the process-based simulations of GHG emission into SWAT-DNDC to enable a comprehensive assessment of conservation practices impacts on GHG emissions in addition to the effects on crop production and water quality.3. Evaluate SWAT-DNDC using in-situ measurements derived from existing and proposed new field experiments where high temporal resolution N2O fluxes will be measured.Field observations for SWAT-DNDC model setup, calibration, and validation will be derived from Agricultural Collaborative Research Outcomes System (AgCROS)and Sustainable Corn Coordinated Agricultural Project (SCCAP) Research Data.We also propose a three-year field experiment to study the impacts of using different conservation practices on N2O emissions and crop yield in the Kelley Drainage Field Plots (KDFP) near Ames Iowa.4. Build and verify SWAT-DNDC in two CEAP watersheds, i.e.,the South Fork Watershed (SFW) and Walnut Creek Watershed(WCW),to simulate crop production, water quality, and GHG emissions in Iowa.5. Conduct SWAT-DNDC simulations with alternative management practices and future climate change scenarios in the Upper Mississippi River Basin (UMRB) to assess their impacts on crop production, water quality, and GHG emissions and to explore tradeoffs between food-water-GHG at different management and landscape configurations, and to inform the best management practices in the Corn Belt.6. Disseminate SWAT-DNDC as an open-source tool to inform actions and policy making to evaluate conservation practices impacts on GHG emissions for agroecosystems.