A New GIS-Nitrogen Trading Tool Concept to Minimize Reactive Nitrogen lossess to the Environment.

Nitrogen (N) is an essential element necessary to maximize agricultural production and sustainability of worldwide agroecosystems. Nitrogen losses to the environment impact water and air quality, both of which have become major environmental concerns for the future generations. This concern has led to the demand for easy to use risk assessment technology tools capable of evaluating how to effectively use best management practices (BMPs) in order to reduce losses of reactive N to the environment. Implementation of these BMPs reduces the loss of reactive N, and these reductions can be traded in air and water quality markets. The new GIS Nitrogen Trading Tool difference in reactive N losses (NTT-DNL_reac) has been defined as the comparison between a baseline scenario and new alternative management scenarios across a series of fields. The new stand-alone version of the Windows XP Nitrogen Losses and Environmental Assessment Package (NLEAP) simulation model with Geographic Information System (GIS) capabilities (NLEAP-GIS) was used to conduct spatial and temporal analyses of no-till systems from a humid Mid-Atlantic US site, manure management systems from a Midwestern US site, and irrigated cropland from an arid Western US site. The NTT-DNL_reac identified the scenario(s) with the greatest potential to maximize temporally and spatially variable field-level savings in reactive N while maintaining agricultural crop production. The savings in reactive N translate into environmental conservation benefits, as well as potential N credits to trade in air and water markets. The NTT-DNL_reac also indicates the potential tradeability of savings in losses of reactive N₂O and its CO₂ equivalents (both contributors to global warming) in the commercial futures market. The new stand-alone NLEAP-GIS can be used to quickly identify the best management scenario that integrates both the spatial and temporal effects to maximize field-level savings in reactive N. This approach also assists in identifying hot spots in agricultural fields, and has contributed to the development of precision conservation management practices that effectively reduce reactive N losses.