New Tools and Incentives for Carbon, Nitrogen, and Greenhouse Gas Accounting and Management in Corn Cropping Systems.

Our overarching goal is to provide corn growers with new C, N, and greenhouse gas (GHG) accounting and management decision tools, and provide policymakers with tools for evaluating costs and benefits of policy incentive options within the context of a changing climate.  Our project focuses on three regions of the U.S. (NY, IA, CO) with distinct climate, soil, and corn management systems.  We use an approach that integrates:  strategic soil sampling for C assessment; biogeochemical models that predict yield, GHG losses, and soil C change; regionally downscaled climate projections; and an economic equilibrium model. Historical and regionally downscaled climate projections in formats required by the modeling teams are being provided. In 2011 we collected over 1500 soil samples stratifying across soil types and management systems and sampling will continue in 2012.  Soil measurements include percent organic matter (OM), percent C and N, active C, bulk density, and visible to near-infrared (VNIR) and mid-infrared (MIR) spectroscopy.  We are developing three dimensional geostatistical models to be used in conjunction with soil database (SSURGO) estimates of OM and strategic soil sampling to predict soil C in unsampled locations and depths. Our DayCent biogeochemical model has a new subroutine for ammonia volatilization, recognizes black C pools, and can assimilate remotely sensed data to improve the plant growth submodel. A method has been developed to estimate soil moisture retention curve parameters from SSURGO for the “Adapt-N” N management tool. Beta testing of “COMET-Farm”, a web-based C and GHG accounting and management tool, begins in 2012. An analytical economics model that considers the behavior of landowners affecting GHG emissions and soil C sequestration in response to policy has been developed and simulated via Monte Carlo methods. Preliminary results have contributed to extension materials and been presented to academic, policy-maker, and farmer audiences.