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Question
"Determination of Biological Oxygen Demand (BOD) can help in suggesting the quality of a water body." Explain.
Solution
Biological Oxygen Demand (BOD) is the amount of dissolved oxygen required by the aerobic organisms to break down the organic material present in the water body at a certain temperature over a certain period of time. Natural water bodies contain a certain level of organic substances that are acted upon and decomposed by microbes.
Determining the BOD of the water body establishes the amount of organic content in it. Presence of more organic wastes increase the biological activity, thus leading to algal blooms. High BOD value indicates more microbial activity, indicating that the water body is polluted.
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