Organic Transitions ILLU-875-62, 2015-2017
Our goals are to:
- Evaluate usability and utility of soil N calculators and models
- Develop affordable ways for farmers to initialize process models that feed decision support tools
- Develop the goCropghg app to allow organic farmers to estimate plant available N and greenhouse gas emissions on their farms
We are leveraging goCrop™, a decision support tool developed by the University of Vermont, that uses integrated web and mobile applications for farmers to plan and report with ease, and the Surrogate Century Soil Organic Matter model (SCSOM), which computes national greenhouse gas (GHG) emissions for agricultural lands (Qin et al. 2017). By drawing on existing collaborations with farmers, farm data, and modeling tools, we are developing modules to estimate plant available nitrogen (PAN) and GHG emissions derived from nitrous oxide release from organic crop systems in the Midwest and Northeast.
So far we have been working to expand the capacity of the SCSOM model (Kwon and Hudson, 2010; Kwon et al., 2013), which was developed using the carbon and plant growth sub-models described in the CENTURY model (Parton and Rasmussen, 1994) and the hydrologic and nitrogen sub-models from DAYCENT (Parton et al., 1998). We are refining model inputs and calibrating and validating the soil N sub-model. Derived variables that will back stop the decision support too include plant available N, SOC, and direct and indirect N2O losses. We are currently working on modeling N mineralization and leaching coefficients derived from SCSOM for region-wide application and refining the picklists that will let us scale field data to farm scenarios modeled at the county that are based on collaborating farmers in IL and VT. To help us better estimate cover crop and manure contributions to plant available N we are carrying out a sampling campaign in 2018.
In addition to this we are studying farmer interests and attitudes about N management tools, climate and greenhouse gas emissions to help us with interface design.