Plz explain (i)Eutrophication (ii)Biochemical oxygen demand

Asked by GARIMA SRIVASTAVA | 4th Mar, 2011, 02:35: AM

Expert Answer:

Dear Student
Eutrophication is the enrichment of an aquatic system by addition of nutrients. It is typically caused by leached phosphorus or nitrogencontaining compounds into lakes, rivers, bays, or other semi-enclosed waters (even slow-moving rivers). The addition of these nutrients disrupts the ecosystem, leading to new species introduction, decreased biodiversity, and toxicity.

Biological Oxygen Demand (BOD) is a measure of the oxygen used by microorganisms to decompose this waste. If there is a large quantity of organic waste in the water supply, there will also be a lot of bacteria present working to decompose this waste. In this case, the demand for oxygen will be high (due to all the bacteria) so the BOD level will be high. As the waste is consumed or dispersed through the water, BOD levels will begin to decline.

We hope that clarifies your query.




Answered by  | 4th Mar, 2011, 11:54: AM

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