Fertilizers and their Impact on Watershed Ecology
Nitrogen and phosphorus pollution ranks as one of the top causes of degradation in some U.S. waters for more than a decade. Large amounts of nitrogen and phosphorus lead to regional water quality problems like algal blooms, hypoxia and declines in wildlife habitat.
“Aerobic conditions” in water ways signifies the presence of oxygen in a hydrological system. The natural cycles of the water feature may be more or less in balance until an excess of nitrate, or nitrogen, and/or phosphate enters the system. At this time, water plants and algae begin to grow more rapidly than normal. There is also an excess die off of plants and algae as sunlight is blocked at lower levels. Bacteria try to decompose the organic waste, consuming the oxygen, and releasing more phosphate which is known as “recycling or internal cycling”. Some of the phosphate may be precipitated as iron phosphate and stored in the sediment where it can then be released if anoxic conditions develop.
