For example , fertilizer which discharges from rivers into the Gulf of Mexico has damaged shrimp fisheries because of hypoxia .
Most of the nitrogen and phosphorus ends up in rivers , lakes and the sea , where excess amounts stress aquatic ecosystems .
Fertilizer which discharges from rivers into the Gulf of Mexico has damaged shrimp fisheries because of hypoxia .
Most of the nitrogen and phosphorus ends up in rivers , lakes and the sea , where excess amounts stress aquatic ecosystems .