Florida agriculture could have caused the dead water discovered by fishermen in January. Nitrogen-rich waters may have flowed from the Shark River after a recent period of above-average rainfall. South Florida had extremely heavy rain by early December, almost two and half times normal.
Larry Brand, a marine biology professor at the University of Miami, says, ?The nitrogen is coming off the sugar cane fields.? Farmers don?t put the chemical directly on their crops; instead, it would have come from the peat on which they grow the sugarcane.