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Secondary Production. Food Web: Concept and Applications. Terrestrial Primary Production: Fuel for Life. Citation: Chislock, M. Nature Education Knowledge 4 4 Eutrophication is a leading cause of impairment of many freshwater and coastal marine ecosystems in the world.
Not only does eutrophication kill other species but the organisms that happen to survive in the water with few oxygen change. Their bodies that were originally used of their surroundings evolve and adapt to the low oxygen level. They were once edible to eat, but as their body changes, so does the human reactions toward it. Many of the fishes that change, they become poisonous to our bodies causing either weakness, blurred vision, burning muscles, difficulty breatlting, memory loss, organ damage, and even death.
Here are other consequences:. Eutrophication can cause serious effects to living resources or their habitats. Marine or estuarine systems with biogenically structured habitat, such as coral reefs or seagrass beds, are especially vulnerable to eutrophication.
Bays, lagoons, enclosed seas, and open coastal waters can also be affected. The accelerated increase in the input of nutrients to the marine system represents a serious threat to the integrity of marine ecosystems and the resources they support.
The effects of eutrophication spread through the water medium, from lakes, ponds, rivers and lagoons draining down to the oceans and consequently killing organisms that maintain a balance ecosystem and the web of life. Scientific evidences have shown the reduction of the diversity of organisms. Our villages, being a part of the world are not exceptions to this phenomenon. As we tried to identify some environmental problems in our areas, we focused our study on the "honey bucket" lagoon, the garbage disposal system and the safety of the source of water the Yukon River used for domestic and industrial purposes, all of which are leading factors to eutrophication.
The village of Kotlik is located in the southern part of Norton Sound along the north tributary of the Yukon Delta fan. It is approximately air miles northwest of Bethel and about miles south of Nome. This gives barges an advance to travel here throughout the mighty Yukon and the Bering Sea. Kotlik has a runway for which planes come through to deliver mail, freight and other supplies our village needs.
These two transportation technologies make it easy for Kotlik to connect to other places of Alaska, U. The village has streets and sidewalks boardwalks that connect the whole village together. There are rarely any dirt roads due to a swampy landscape.
Also Kotlik is a flat plain land formed village. The City of Nunam lqua is located on the south fork of the Yukon River approximately nine miles south of Alakanuk and 18 miles southwest of Emmonak.
It is the Yukon Kuskokwim Delta. This location affords easy access by boat and barge approximately five months per year.
Major barge lines deliver shipments of fuel and other bulk supplies to the city several times each summer. Because of soft marshy ground, four wheeler travels within the community is generally limited to the boardwalks. Residents use snow machines for local travel during the winter.
The U. Census calculated the population of Nunam Iqua in at residents. Kotlik and Sheldon's Point Nunam Iqua are both Yupik Native, villages located in rural Alaska, which undergoes similar environmental issues such as waste disposal, source of water for domestic and business purposes, which are not unique to bush villages that are known as Second Class cities.
Among the environmental issue that we look to the research is how the sewer is dumped into the honey bucket lagoon. It is part of our findings that locations like this would threaten the quality of the environment and foremost would cause eutrophication. So the consequences of eutrophication are the problem ofleeching the polluted and hypoxic conditions down the soil to the river and estuaries ending in the Bering Sea. This causes dead zones. Figure 1. Massive oil due to the Exxon Valdez spill in AIaska.
Source: Google Images. Algae blooms resulting in red tides Source: Google Images. Phosphate cycle Source: Google Images. Figure 7. Nitrogen cycle Source: Google Images.
Figure 8. Created by satellite, the red circles on this map show the location and size of many of ollr planet's dead zones. Black dots show where dead zones have been obselved, but their size is unknown. Darker blues in this image show higher concentrations of particulate organic matter, an indication of the overly fertile waters that can culminate in dead zones. Contact: Alaska Sea Grant web coordinator. Sponsors Archives Links.
Research paper archives Information for coaches and teams Art show information How to become a sponsor Archives. Introduction Over the last century mankind has transformed the sea from a clear-water ecosystem into a eutrophic nutrient-rich marine environment. Here are some fcts that marine scientists recorded as evidences of this global problem: Fact I : In , a single hypoxic event in the New York Bight that covered about km 2 caused mass mortality of demersal fishes and benthos and blocked the northward migration of bluefish Milstein, Karlson, Fact 4 : In the northern Gulf of Mexico, the occurrence and extent of the severe hypoxia are tightly coupled with freshwater discharge from the Mississippi River, which delivers large quantities of nutrients from U.
Figure 2 Fact 6 : Severe algal blooms can change the seawater to various colors, often called "red tides". Figure 3 What is eutrophication? Figure 4 A more complex definition of eutrophication can be described as having too much plant growth in a river or lake cuts which down oxygen causing the suffocation and death of water animals.
Figure 5 The Natural Recyclization of Phosphates Organisms, such as the animal shown needs phosphorus to build proteins and nucleic acid.
The World's Dead Zones Dead zones are caused by agricultural runoff, especially nitrogen-rich fertilizers, as well as the burning of fossil fuels. Some of the consequences of eutrophication include destruction of aquatic systems and reduction in water quality. As per Wikipedia ,. Negative environmental effects include hypoxia, the depletion of oxygen in the water, which may cause death to aquatic animals. Eutrophication is predominantly caused by human action.
Agricultural practices and the use of fertilizers on lawns, golf courses, and other fields contribute to nutrient accumulation. When these nutrients with high concentrations of phosphorous and nitrogen are washed by surface runoff into lakes, rivers, oceans and other surface waters when it rains, the hungry plankton, algae and other aquatic plant life are well fed and their photosynthesis activity is increased.
This causes dense growth of algal blooms and plant life in the aquatic environments. Concentrated animal feeding operations CAFOs are as well a main contributor of phosphorus and nitrogen nutrients responsible for eutrophication. The concentrated animal feeding operations normally discharge the nutrients that find way into rivers, streams, lakes, and oceans where they accumulate in high concentrations thereby plaguing the water bodies by recurring cyanobacterial and algal blooms.
In some parts of the world, especially the developing nations, sewage water is directly discharged into water bodies such as rivers, lakes, and oceans. As a result, it introduces high amounts of chemical nutrients therefore stimulating the dense growth of algal blooms and other aquatic plants which threatens survival of aquatic life in many ways. Some countries may also treat the sewage water, but discharge it into water bodies after treatment. As much as the water is treated, it can still cause the accumulation of excess nutrients, ultimately bringing about eutrophication.
The direct discharge of industrial waste water into water bodies presents similar outcomes. Natural events such as floods and the natural flow of rivers and streams can also wash excess nutrients off the land into the water systems thus causing excessive growth of algal blooms. Also, as lakes grow old, they naturally accumulate sediments as well as phosphorus and nitrogen nutrients which contribute to the explosive growth of phytoplankton and cyanobacterial blooms.
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