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Eutrophication Essay

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What is eutrophication?

Eutrophication is, in the simplest terms, too much of a good thing. It occurs when too many nutrients are deposited into a body of water, throwing off the established balance of production and consumption of organic matter. Eutrophication can take place in ponds, lakes, rivers, and oceans. At first, the overload of nutrients in the body of water encourages plant growth. However, soon this excess of organic material uses up most of the available oxygen in the water, taking it away from the other plants and animals. These other organisms can no longer survive with such depleted oxygen levels and die off, creating what is referred to sometimes as a "dead zone", devoid of life. Below is a table of the …show more content…

In this diagram, phosphorous in the surface runoff fertilizes small floating aquatic plants. As these aquatic plants proliferate, sunlight penetration is reduced. Submerged aquatic vegetation can no longer survive, and as they die and decompose, oxygen levels in the water are also depleted. Eventually, animals die too, due to lack of oxygen. Some probable causes of this excessive nutrient runoff include sewage treatment plant leakage, septic tank leakage, urban runoff, agricultural runoff, channel dredging, and loss of wetlands. back to top

What are the effects of eutrophication?

As mentioned earlier, the initial effect of eutrophication- increased productivity- is deceptively good. However, the first indications of eutrophication's ill effects are such visual changes as muddled and discolored water, coupled with a noxious odor. This change in water clarity is a result of the primary effect of eutrophication, which is algal blooms. To the left is an example of such an algal bloom. For more examples of what algal blooms look like, click on the image. Algal blooms occur when excess nutrients cause a proliferation of algae. These algae blooms, known as Harmful Algal Blooms (HABs) because of their effects, are deceptive as well. Because they photosynthesize, one would think they actually add oxygen to the water, helping it. While algal blooms do

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