Fertilizer and manure runoff into the Mississippi River needs to be cut sharply to repair the oxygen-deprived “dead zone” in the Gulf of Mexico, according to the Environmental Protection Agency. This is because every year an area of the Gulf as large as New Jersey becomes depleted of oxygen and fish, shrimp and other species that show a significant decline within the dead zone, the report said.
In 1999, a White House study concluded that the most cost-effective way to protect the Gulf would be to reduce fertilizer use by 20 percent and to restore 5 million acres of wetlands that could trap nutrients before they reach the Mississippi and its tributaries. The Gulf’s “dead zone” doubled in size to about 7,000 square miles after widespread Midwest flooding in 1993, but has fluctuated annually since then, depending on water flows in the Mississippi. The problem stems from the algae that thrives on the excess nutrients and hogs the oxygen in the water that is needed by fish, shrimp and other aquatic life.
