INTEGRATED HYDRO-ECONOMIC AGRICULTURAL LAND USE MODELING FOR NUTRIENT RUNOFF MANAGEMENT

Objective 1. Expand the IHEAL model to include additional elements.The proposed expansions are:1a. Add cotton, rice, barley and alfalfa to the model.1b. Add P management via prescribed BMPs or as fertilizer use depending on the location.1c. Add spatially explicit BMPsstarting with the MRB where applicable.Objective 2. Estimate the opportunity cost of reducing nutrient runoff .The IHEAL.2 will be used to estimate the opportunity costs of reducing nutrient runoff to the Gulf and other outlets.Objective 3. Quantify cross-watershed nutrient runoff leakages.The spillover effects of nutrient runoff reduction to the Gulf on nutrient runoff outside the MRB will be quantified. Nutrient runoff reduction to the Gulf will be reevaluated with explicit constraints on runoff to other regions.Objective 4. Quantify the water scarcity impacts. Cropland in the Lower MRB relies heavily on the Mississippi River Valley alluvial aquifer for irrigation water. The Ogallala aquifer, mostly located within the MRRB and ARB, is also a major irrigation water source in some of the counties.4a. The effect of reducing N and P runoff on irrigation in water-stressed locations will be examined.4b. Nutrient runoff abatement outcomes will be evaluated under constrained irrigation in water-stressed areas. Irrigation will be restricted from increasing beyond the baseline (business as usual) values when nutrient runoff is constrained and runoff abatement outcomes like opportunity costs, prices, and acreages will reevaluated. In addition, we will examine the impacts of potential future declines in irrigation capacities on nutrient runoff.Objective 5. Investigate the interdependencies between N and P runoff reductions . Starting with select sub watersheds, HAWQS (Hydrological and Water Quality System) platform will be used to obtain parameters needed to examine the interdependencies between N and P runoff.