The same happens to all plants and animals, everything ages and eventually dies, but certain things can happen to make a plant or animal age faster than it should. If too much nitrogen enters a water source it will become polluted and eventually lead to eutrophication. Agriculture is the major source of the pollutants in a water source because of the fertilizer runoff and livestock waste. If a major nitrogen problem occurs, it is hard to determine where the start of a problem is because nitrogen runs off of large areas of land into streams, then creeks, and then rivers. This type of a pollution problem is a non-point source.
Farmers can help to prevent nitrogen pollution by contour plowing.
Contour plowing is a process of plowing fields with the contour of the land instead of against it. This keeps nitrogen from running off the land faster than it should. Also crop rotation helps prevent nitrogen pollution. An example of crop rotation is when soybeans are grown one year and corn the next. Human Health Risk Nitrogen pollution of a water source can cause many health risks to humans.