EUTROPHICATION by: Gianne Defensor

EUTROPHICATION as an environmental problem
by: Gianne C. Defensor

Before I start to discuss about how a natural cycle like EUTROPHICATION became an environmental problem, I will define first the meaning of EUTROPHICATION. How come a natural cycle which is supposed to be a help became an environmental problem? Find out as you read the next sentences below.

Eutrophication is a natural cycle whereby water bodies, such as lakes, estuaries, or slow-moving streams receive excess nutrients that stimulate excessive plant growth (algae, peryphiton attached algae, and nuisance plant weeds). This enhanced plant growth, often called an algal bloom, reduces dissolved oxygen in the water when dead plant material decomposes and can cause other organisms to die. Nutrients can come from many resources, such as fertilizers applied to agricultural fields, golf courses, and suburban lawns; deposition of nitrogen from the atmosphere; erosion of soil containing nutrients; and sewage treatment plant discharges. Water with a low concentration of dissolved oxygen is called hypoxic or low oxygen.

There are three main stages that make up the essential cycle of eutrophication: oligitrophy, mesotrophy, and eutrophy. These stages represent the lake from its beginning to its death, specifying how old the lake is. When one or more of this stages is sped up or even skipped over completely, the natural balance is disrupted and can result in the annihilation of the body of water. Oligitrophy is the beginning stage of the lake. The lake is rich in dissolved oxygen, but lacks essential plant nutrients such as nitrogen and phosphorus. This means that the lake also has a lack of fertility that limits animal life in the lake.

In its mid-life, the lake becomes mesotrophic. The nutrients, such as decaying organic matter or man made items such commercial fertilizers, flowing into the lake accumulate in the bottom sediments along with nutrients that settled from decay of the lake’s own organisms. Some of this nourishment recycles into the upper waters where it is photosynthesized into greater production of phytoplankton.

The final stage of EUTROPHICATION is eutrophy. This stage occurs when the lake becomes old and, despite its old age, its fertility hastens. When the lake’s fertility hastens it increases the supply of nutrients in the water and thus generates lush growth among rooted plants near the shore and between floating phytoplankton. The lake’s water soon becomes turbid with decaying organic matter from plants and animals and the supply of dissolved oxygen in the water becomes depleted by the rapidly growing plants that use all the oxygen they need to live, which is a high majority of it. The absence of oxygen causes anaerobic bacteria to attack organic matter thus releasing hydrogen sulfide. This signifies the end of the lake’s days as the plant life covers up the lake, turning it into a swamp or bog.

So after knowing the meaning of EUTROPHICATION, maybe now, you also know the reason why it is considered as environmental problem because it produces excess nutrients that the lake or a body of water receives which stimulates excessive plant growth in the form of algae.



Gianne:)