Evaluating Alternative Options for Managing Nitrogen Losses from Corn Production

Widespread and intensive agricultural activity, particularly corn production, has resulted in large amounts of nitrogen (N) loading to surface and groundwater1,2. Elevated N levels in streams and rivers causes a spectrum of different problems including biodiversity loss, crop yield loss, and negatively affecting human health3. Nutrients transported through the Mississippi River Basin (Figure 1) have been blamed for what are referred to as the “dead” zones (low oxygen water) formed in the Gulf of Mexico4,5. According to the United States Environmental Protection Agency (US-EPA) Hypoxia Task Force, the 2017 hypoxic zone measured 8,776 square miles, and reducing this size to a more acceptable level by 2035 will require at least a 45% reduction in the N load exported by the Mississippi and Atchafalaya Rivers6,7. This Policy Brief explores some alternative means of achieving this abatement target.

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