Are the agricultural sources that contribute nutrients to the Gulf the same for nitrogen and phosphorus?
|Back to Top| Modeled findings reveal important differences in the agricultural sources for nitrogen and phosphorus. The findings help fill important gaps in information on sources of phosphorus in the Mississippi River Basin at a time when recognition is expanding that phosphorus is an important contributor to Gulf hypoxia. The joint federal-state Gulf of Mexico Hypoxia Task Force is evaluating recommendations by EPA’s Science Advisory Board to set reduction targets of at least 45 percent for both nitrogen and phosphorus in an effort to shrink the size of the “hypoxic zone” to 5000 square-kilometers by 2015. The current 5-year average size of the hypoxic zone is 14,644 square kilometers, almost three times the size of the goal. States and EPA may therefore need to adopt a dual nutrient management strategy in order to reduce the size of the hypoxia zone in the Gulf.
