Original Research - Eutrophication

Two major marine related environmental issues are Eutrophication and Algal Blooms. Both of these issues negatively affect water bodies around the world, destroying ecosystems and harming humans. Eutrophication is the addition and overabundance of nutrients to a body of water. Algal Blooms are a population explosion of algae in a body of water. Both of these occurrences are major environmental problems in the world today

The main causes of eutrophication are runoff and inadequately treated wastewater. Runoff rich in fertilizer pollutants is a major cause of eutrophication. The major components of fertilizer, nitrates and phosphates, are designed to stimulate plant growth in farms and lawns. These chemicals, if introduced to a water system will also encourage algae growth. Runoff from agricultural and residential sources is the main contributing factors to the introduction of nutrients into the water column. A freshly fertilized farm field or house lawn will have some of its fertilizer washed away during a rain storm. The rainwater carries this fertilizer from the original source to a water source. This introduces the nutrients to the aquatic system, causing eutrophication. Another cause of eutrophication is the release of insufficiently treated waste water into a water system. The discharge of sewage, rich in nutrients, to the water system can cause eutrophication. 

The main cause of an Algal Bloom is Eutrophication. As stated before, Eutrophication is the overabundance of nutrients in the water column. Algae and other plankton use these nutrients to thrive, grow, and reproduce, causing rapid population growth. This population expansion is called an “Algal Bloom.” Algal Blooms are also known as “red tides.” Algal blooms have two major devastating environmental effects. After the nutrients in a water body are depleted by the algae, the algae can no longer survive. This causes a massive decline in the algae population because it can no longer be sustained. In the process of dying, the algae exhaust the dissolved oxygen in the water. Eventually, the dissolved oxygen in the water declines to such a level, that fish and other aquatic species can no longer survive in the ecosystems. This depletion of oxygen is known as a “dead zone.” A Harmful Algal Bloom is an algal bloom where the species of algae that has undergone a population expansion either is toxic, or unsafe to other organisms, including humans. Harmful Algal Blooms have been tied to shellfish poisonings and the death of endemic species to the ecosystems involved.

Many possible solutions have been developed to stop Eutrophication. The reduction of runoff and the instillation of Riparian buffer zones are two major preventative methods to curtail eutrophication. Governmental regulation of the type, amount, application, and timing of fertilization has helped reduce runoff pollution from agricultural and residential sources. The addition of Riparian buffer zones, the area between land and a river, help to reduce runoff into river sources. These zones act as a divider between land and water, and can trap pollutants in runoff before they reach the river. These solutions greatly reduce runoff containing pollutants and unwanted nutrients into the water column. The reduction of nutrients helps decline the rate of eutrophication. Without eutrophication, the occurrence of Algal Blooms declines. Each of these processes has consequences on other processes down the sequence of events. By eliminating pollution at its source, algal blooms can be brought to an end.