New Research Initiative on Northern Gulf of Mexico Hypoxia and Land Use in the Watershed

The annual extent of the seasonal oxygen-depleted hypoxic (dead) zone that forms in the Northern Gulf of Mexico is about three times the target goal of the Hypoxia Action Plan. The 2007 scientific reassessment of causes and consequences of these hypoxic conditions suggests that both nitrogen and phosphorous loadings from the Upper Mississippi River Basin and Ohio River Basin stream systems are significant contributors to the size and duration of the zone, accounting for about 70% of the total nitrogen and nearly 60% of the phosphorous loading to the Gulf. Land use, primarily from agriculture, is a key driver of these nutrient loadings and is the result of decisions by more than 500,000 individual producers in the region.

This project takes a fresh look at the natural and human dynamics of this enormously complex system by developing integrated and data-rich models that capture the many spatial and temporal non-linearities associated with scaling up the impacts from individuals to the watershed under different scenarios. The research will produce the first complete modeling system that traces agricultural land-use decisions—made at the field scale in the Upper Mississippi, Ohio, and Tennessee Basins through both environmental and hydrologic components—to downstream water quality effects, including the size of the hypoxic zone in the Gulf of Mexico. This project will demonstrate how to integrate human and natural process models using the powerful tools of evolutionary algorithms and identify cost-effective placement of conservation practices within the landscape. Uniquely, the model includes two feedback mechanisms: (a) feedbacks via the market, and (b) feedbacks via endogenous policy in the form of adaptive management. When complete, the modeling system will provide an effective tool for the design and implementation of environmental policy to address both Gulf hypoxia and water quality concerns in the local watersheds.