Eutrophication is the artificial enrichment of a water body or aquatic system with phosphorus and nitrogen nutrients, usually with an excessive amount of nutrients. This process causes excessive plant and algae growth and, due to biomass loading, can lead to oxygen depletion in the water body. For example, in response to increased nutrient levels, there is a large increase in phytoplankton, called algal blooms, that occurs in the body of water. Nutrients can come from animal dung, fertilizers often used in agriculture, and wastewater that is carried by rain or irrigation into bodies of water through surface runoff. This will increase nutrient levels and contribute to eutrophication. Eutrophication can be divided into cultural eutrophication caused by human activity and natural eutrophication which is a natural process. Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”?Get the original essay Cultural eutrophication is the process that accelerates natural eutrophication due to human activity. Due to land clearing and city construction, land runoff is accelerated and more nutrients such as phosphates and nitrates are supplied to lakes and rivers and then to estuaries and coastal bays. Additional nutrients are also provided by sewage treatment plants, golf courses, fertilizers, farms and untreated sewage in many countries. Natural eutrophication is a natural process. Eutrophication occurs in many temperate grassland lakes. Paleolimnologists now recognize that climate change, geology, and other external influences are critical to regulating the natural productivity of lakes. Some lakes also demonstrate the opposite process, becoming less nutrient rich over time. The main difference between natural and anthropogenic eutrophication is that the natural process is very slow and occurs on geological timescales. Eutrophication is mainly caused by human action due to its dependence on the use of fertilizers. Agricultural practices and fertilizer use on lawns, golf courses and other fields contribute to the buildup of phosphates and nitrates. When the concentration of nutrients increases until the soil is no longer able to assimilate them, the nutrients are transported by rain to rivers and groundwater which flow into lakes or seas. Plankton, algae and other aquatic plants are then well nourished and their photosynthesis activity is increased. They grow and reproduce more quickly, leading to dense growth of algal blooms and plant life. This will disrupt the normal functioning of the ecosystem and cause many problems. (See Annex 1) On the other hand, eutrophication can be caused by the input of untreated wastewater as well as discharges from wastewater treatment plants. We can see that wastewater is directly discharged into water bodies such as rivers, lakes and oceans in various parts of the world, especially in developing countries. This results in the release of a large amount of chemical nutrients that stimulate the disproportionate growth of algae and other aquatic plants that in many ways threaten the survival of aquatic life. Some countries may also treat wastewater, but still discharge it into water bodies after treatment. Even if the water is treated,it can nevertheless cause an accumulation of excess nutrients and lead to eutrophication. (See Appendix 1) In addition to this, it is also caused by aquaculture. Aquaculture is a technique of growing shellfish, fish, and even aquatic plants in waters containing dissolved nutrients. Therefore, uneaten food particles as well as fish excretions can significantly increase nitrogen and phosphorus levels in the water if aquaculture is not properly managed. This will result in dense growth of microscopic floating plants. Finally, eutrophication can be caused by natural events such as flooding and the natural flow of rivers and streams. Excess nutrients will be removed from the land and flow into water systems, causing excessive growth of algae blooms. Additionally, as lakes age, they naturally accumulate sediments such as phosphorus and nitrogen nutrients that contribute to the explosive growth of phytoplankton and cyanobacteria blooms. How is it going? First, excess nutrients are applied to the soil. Then, they are evacuated to ponds, lakes or rivers. This promotes the rapid growth of photosynthetic organisms, especially algae. This leads to a population explosion known as an algae bloom. Algae blooms prevent sunlight from reaching the bottom of the body of water. As a result, aquatic plants beneath the algae bloom die because they cannot capture sunlight to carry out photosynthesis, further decreasing the oxygen supply to the water. Eventually the algal bloom dies and sinks to the bottom of the lake, the decaying microorganisms, especially aerobic bacteria, grow rapidly and quickly consume oxygen to breathe. Aerobic bacteria consume oxygen faster than it can be replenished. This causes an increase in biochemical oxygen demand (BOD), leading to depletion of oxygen in the water. Due to the lower level of oxygen concentrations, larger life forms, such as fish, cannot survive suffocation. In extreme cases, if the oxygen level continues to drop until the water is completely deoxygenated, aerobic bacteria will grow and release toxic substances. gases harmful to aquatic life. This body of water can no longer support life and this process is called eutrophication. (Reference Appendices-2) For aquatic plants, they need two essential nutrients to grow such as nitrogen (N) and phosphorus (P). In a healthy lake, biochemical oxygen demand (BOD) should be low, indicating better water quality, and nutrients should be present in small amounts for aquatic plants to survive. Conversely, a major water pollution problem will occur if nutrients are present in large quantities. Too many nutrients will stimulate rapid growth of plants and algae, clogging waterways and sometimes creating serious algae blooms. If this situation occurs, the survival of fish and other forms of aquatic life will be threatened. Algae blooms caused by excess nutrients in the body of water will limit the amount of dissolved oxygen needed for aquatic life forms to breathe. When algae and aquatic plants die and decompose, it promotes detritus growth and oxygen removal occurs. When dissolved oxygen reaches hypoxic levels, underwater animal and plant species, such as shrimp, fish and other aquatic biota,..