The zone at the end of the Mississippi River has little fish or other marine life because nitrogen fertilizer used to grow corn washes down the river and feeds microscopic organisms that in turn absorb oxygen, according to Bloomberg.
As a result, fishing operations for shrimp and other sea life are increasingly threatened. The zone has doubled since 1985.
Farmers this spring planted more corn acres than in any year since 1944 to take advantage of soaring prices. Ethanol plants use corn to make the alternative fuel.