Eutrophication occurs when the environment becomes enriched with nutrients. All living things need specific nutrients to live. Because too much or too little can cause problems, nature does a good job providing the right amount of nutrients. This is true in aquatic ecosystems because aquatic ecosystems are very dynamic. water is oligotrophic when too few nutrients are present. It makes sense that serious problems arise when there is not enough nutrition available for the variety of organisms living in an aquatic environment. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get an Original Essay However, problems can also arise when the aquatic system has an overabundance of nutrients. We get eutrophication when this happens. When too many nutrients, such as nitrogen and phosphorus, are present, a eutrophic stream, river, or lake occurs. usually due to runoff from surrounding land. Algae, plankton, and other microorganisms love these types of nutrients, and when they are abundant, these aquatic organisms can take over. When the river, lake or other water system becomes eutrophic, it can have serious negative effects on other organisms like birds, fish and even humans. How it happens: Excess fertilizer from farmland washed by rainwater into the nearby pond or water. . The nutrient level in the water increases when fertilizers accumulate in the water. This phenomenon is called eutrophication. This results in faster growth and reproduction of phytoplankton. This will lead to algae blooms. Aquatic plants cannot photosynthesize because sunlight is blocked by algae. Sediment at the bottom of the pond forms when aquatic plants and algae die. This affects the pond ecosystem and promotes the growth of detritus. All the oxygen in the water is consumed by the detritus as it decomposes. This leads to an increase in biochemical oxygen demand (BOD). Lack of oxygen in water leads to the death of many aquatic organisms. Toxic byproducts that can poison the pond ecosystem are produced by certain species of algae. How to determine BOD: A water sample is taken from a pond. If the amount of oxygen needed to decompose the organic matter in the sample is high, then the BOD is high. This means that the water sample from the pond is very heavily polluted. BOD increases when water is very heavily polluted by bacterial pollution. BOD decreases when water is very heavily polluted by toxic pollution. Causes: Fertilizers Human actions cause eutrophication. Man likes to depend on the use of nitrate and phosphate fertilizers. Lawns, golf courses, farms and other fields must be heavily fertilized by humans. These fertilizers run off into streams, rivers, lakes and oceans when it rains. Hungry algae, plankton and other aquatic plants are well fed. This increases the rate of photosynthesis activity. This causes dense growth of plant life such as water hyacinths and algal blooms in aquatic environments.Concentrated Animal Feeding OperationsConcentrated animal feeding operations (CAFOs) are the major contributor to nitrogen nutrients and phosphorus responsible for eutrophication. Concentrated animal feeding operations normally release high quantities ofnutrients. It is found in one way or another in lakes, streams, rivers and oceans where it accumulates in very high concentrations. Due to recurrent proliferations of cyanobacteria and algae, which ravage bodies of water. Direct discharge of sewage and industrial waste into water bodies. In developing countries, wastewater is piped directly into bodies of water such as oceans, lakes and rivers. This results in the introduction of large amounts of chemical nutrients. This stimulates the dense growth of other aquatic plants and algae blooms, which threatens the survival of aquatic life in many ways.AquacultureA technique of growing fish, aquatic plants without soil, and shellfish in water .containing dissolved nutrients is known as aquaculture. Aquaculture is also considered one of the major contributors to eutrophication as it is widely practiced in recent times. Uneaten food particles as well as fish excretions will increase phosphate and nitrogen levels in the water if aquaculture is not properly managed. This will result in dense growth of microscopic floating plants. Natural events Eutrophication can also be caused by natural events. If a lake, river or stream floods, it can wash away any excess nutrients from the land and into the water. However, in areas that are not surrounded by fertilized land, eutrophication is less likely to occur. Example: Lake Erie was the most publicized example of eutrophication in the 1960s and 1970s. It was called the "dead lake." Originating from heavily developed agricultural and urban lands, the smallest and shallowest of the five Great Lakes has been awash for decades with nutrients. As a result, plant and algae growth has smothered most other species living in the lake. This made the beaches unusable due to the smell of rotting seaweed washing up on the shores. (see appendix 8) Effects: Threatens the survival of other forms of aquatic life and fish. Other photosynthetic plants and phytoplankton grow explosively when aquatic ecosystems experience an increase in their nutrients. This is commonly referred to as algae blooms. This causes algae blooms to limit the amount of dissolved oxygen that is needed for other plant and animal species in the water to breathe. When algae or plants die and decompose, oxygen depletion occurs. When hypoxic levels are reached by dissolved oxygen, underwater plant and animal species, such as fish, shrimp, and other aquatic species, suffocate to death. In extreme cases, bacteria growth is favored by anaerobic conditions which produce toxins dangerous to seabirds and mammals. Light penetration into lower water depths is reduced due to phytoplankton growth. This leads to loss of aquatic life, aquatic dead zones and reduced biodiversity. Limits access to drinking water and deteriorates water quality. Algae blooms are highly toxic. The growth of more toxic bacteria is favored when water reaches the anaerobic condition. This leads to a decrease in the availability of drinking water and a significant deterioration in water quality. Water supply systems are blocked due to dense growth of photosynthetic bacteria and algae blooms on the water surface. This therefore limits the availability of running water. Toxic algae blooms.