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In the human-induced process called acid...

In the human-induced process called acid precipitation, the main biogeochemical cycles that are altered are the _____ cyucles and one effect in lakes is to ____ population of nitrifying bacteria.

A

phosphorus and nitrogen, decrease

B

nitrogen and sulphur, decrease

C

nitrogen and sulphur, increase

D

phosphorus and sulphur, decrease

Text Solution

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The correct Answer is:
B
Acid rain or acid precipitation is rainfall and other forms of precipition with a pH of less than 5. Acid rain is caused by large scale emission of acidic gases into the atmosphere from thermal power plants, industries and automobiles. The common ones are sulphur dioxide, nitrogen oxides `(NO_(X))`, volatile organic (VOCs) and hydrogen chloride. Sulphur dioxide and nitrogen oxides are changed in the atmosphere into sulphuric aci9d and nitric acid by combining with oxygen and water. When such rain falls on land, it acidifies the soil and water. Nitrifying bacterial populations and thereby densities decrease in acid stressed water and soil.
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