Eutrophication occurs when the environment becomes enriched with nutrients. All living things need specific nutrients to live. Since too much or too little can cause problems, nature does a good job of providing the right amount of nutrients. This is true in aquatic ecosystems because aquatic ecosystems are so dynamic. water is oligotrophic when too few nutrients are present. It stands to reason that serious problems arise when there is not enough nutrition available for the variety of organisms that live in an aquatic environment. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original Essay However, problems can also arise when the aquatic system has an overabundance of nutrients. When this happens, eutrophication occurs. When too many nutrients, such as nitrogen and phosphorus, are present, a eutrophic stream, river, or lake forms. 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. It can have serious negative effects on other organisms such as birds, fish and even people, when the river, lake or other aquatic system becomes eutrophic. How it happens: Excess fertilizer from farmland washed away by rainwater into the pond or pond water nearby. The nutrient level in the water increases when the accumulation of fertilizers in the water occurs. This phenomenon is called eutrophication. This causes phytoplankton to grow and reproduce more rapidly. This will result in 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's ecosystem and encourages debris growth. All the oxygen in the water is consumed by the debris carrying out decomposition. This causes an increase in biochemical oxygen demand (BOD). The lack of oxygen in water causes the death of many aquatic organisms. Toxic byproducts that can poison the pond ecosystem are produced by some species of algae. How to determine the body: A water sample is taken from a pond. If the amount of oxygen needed to decompose organic matter in the sample is high, then the BOD is high. This means that the pond water sample is very polluted. BOD increases when water is heavily polluted by bacterial pollution. BOD decreases when water is 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 need to be heavily fertilized by people. These fertilizers wash off into streams, rivers, lakes and oceans when it rains. Hungry algae, plankton and other aquatic plants are fed well. This increases the rate of photosynthesis activity. This causes dense growth of plants such as water hyacinths and algae blooms in aquatic environments. Concentrated Animal Feeding Operations The primary contributor of nitrogen and phosphorus nutrients responsible for eutrophication are concentrated animal feeding operations (CAFOs). Concentrated animal feeding operations typically discharge high amounts of nutrients. Somehow it makes its way to lakes, streams, rivers and oceans where it accumulates in very high concentrations. Through recurring blooms of cyanobacteria and algae, which plague bodies of water. Direct discharges ofsewage and industrial waste into water bodies In developing countries, wastewater is channeled directly into water bodies such as oceans, lakes and rivers. This results in high amounts of chemical nutrients being introduced. This stimulates dense growth of other aquatic plants and algal blooms that threaten the survival of aquatic life in many ways. Aquaculture A technique of growing fish, soilless aquatic plants and shellfish in water containing dissolved nutrients is known as aquaculture. Aquaculture also qualifies as one of the major factors contributing to eutrophication as it is widely practiced in recent times. Uneaten food particles along with fish excretions will increase phosphate and nitrogen levels in the water if aquaculture is not managed properly. 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 could wash all the excess nutrients out of the soil and into the water. However, in areas 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”. From heavily developed agricultural and urban lands, the smallest and shallowest of the five Great Lakes has been awash with nutrients for decades. As a result, plant and algae growth has drowned out most of the other species living in the lake. It left beaches unusable due to the smell of rotting seaweed washing up on the shores. (refer to Appendix 8)Effects:Threatens the survival of other aquatic life and fishOther photosynthetic plants and phytoplankton grow explosively when aquatic ecosystems experience increased nutrients. This is commonly known as algal blooms. This causes algal blooms to limit the amount of dissolved oxygen needed for other plant and animal species in the water to respire. When algae or plants die and decompose, an oxygen deficiency 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, bacterial growth is encouraged by anaerobic conditions which produce toxins dangerous to seabirds and mammals. Light penetration into the shallowest depths of water is reduced due to the growth of phytoplankton. This causes loss of aquatic life, dead aquatic areas and also reduces biodiversity. It limits access to drinking water and deteriorates water quality. Algal blooms are highly toxic. The growth of more toxic bacteria is favored when the water reaches the anaerobic condition. This causes a decrease in the availability of clean drinking water and a vast deterioration in water quality. Water systems are blocked due to dense growth of photosynthetic bacteria and algae blooms on the water surface. Hence, this limits the availability of piped water. Toxic algae blooms have blocked many water supply systems around the world. For example, in 2007, more than 2 million residents of Wuxi, China, did not have access to drinking water for more than a week due to a severe attack by algal blooms on Lake Taihu. (see appendix 9) Endangering fisheriesIncreased growth of tiny floating plants such as photosynthetic bacteria and algae and the growth of extensive, dense mats of floating plants such as water hyacinths and Nile cabbage is a.