Effects of Fertilizers on an Aquatic Environment

Algae Growth

• When an aquatic environment is flooded with nutrients from fertilizers, this increases the reproduction of algal organisms that are always present in the water. While some algae is necessary -- it turns carbon dioxide released by aquatic animals into oxygen -- too much algae is a problem. When fertilizer raises the nutrients to a level that other plants and animals cannot consume, the algae will grow out of control and form a layer on the top of the water. This happens in environments as small as ponds and as large as the ocean. Once this layer of algae forms, it can block sunlight from reaching the other plants and animals in the environment. Prolonged algal blooms will eventually strangle the other life in the ecosystem.

Nitrates and Fish

• Nitrogen is one of the key nutrients needed by plants to thrive. Most fertilizers designed for lawn and garden use contain a high percentage of nitrogen, which is in a form that is readily usable by plants. When fertilizer makes its way into an aquatic ecosystem from lawn and garden applications or from improperly applied pond fertilizers, a potentially damaging nitrogen level can develop. Some wildlife -- such as fish -- cannot tolerate high amounts of nitrogen in their systems, and prolonged exposure can result in the death of entire populations of fish.

Drinking Water Storage

• When fertilizers make their way into reservoirs or leach through the soil to contaminate sources of drinking water, the results can lead to blue-baby syndrome. High nitrogen content can be extremely harmful to young children less 6 six months old; nursing mothers who ingest the water can pass the nitrogen content to their children. One of the signs that drinking water has been contaminated by fertilizers is a strong, bad odor coming from the water. The water should be filtered and checked by a local college extension office. If there are fertilizers present in the drinking water, there are most likely problems occurring at the water source such as algae growth.

Beneficial Effects

• Not all fertilizers have a bad effect on an aquatic environment. When applied correctly, fertilizers can make aquatic plants healthier and able to sustain larger populations of bigger animals. In large, high-traffic areas, fertilizers can be applied in moderation to keep up the algae content of a pond to make sure there is enough recycling of oxygen and carbon dioxide to sustain life. Similarly, fertilizing ponds that have a thriving animal environment will help keep enough plant life in the pond to support them.

  The contents of fertilizers used in these environments differ from those used on land, and while they include some of the same base nutrients they are in different forms such as diammonium phosphate and ammonium polyphosphate. There is a delicate balance between responsible fertilizing and flooding the environment with unhealthy chemicals.