Question

All of the following activities affect the quality and quantity of clean water except

• A. Industrial waste disposal into waterways
• B. Over grazing of livestock
• C. Oil spills
• D. Excessive use of artificial fertilizers in agriculture
• E. Over fishing and hunting of marine organisms

Answer 1

Answer: (B)

Over grazing of livestock

A. Industrial waste disposal into waterways pollutes water as many harmful substances and chemicals are released in the water bodies by the industrial waste water.

B. Overgrazing of livestock can destroy the natural vegetation which in turn will lead to soil erosion because soil particles are held tightly by the plant roots. If no vegetation is there, soil particles get loosen and can be easily carried away by wind or water.

C. Oil spill is the release of petroleum in water bodies. A layer of petroleum hydrocarbon is formed over the surface of the water and this leads to decline in oxygen quantity of the water.

D. Excessive use of fertilizers in agriculture pollute water bodies when runoff occurs and this can also lead to eutrophication.

E. Over fishing and hunting of marine organisms will affect the biodiversity of marine ecosystem and this will affect the quality of fresh water.

Hence, overgrazing of livestock will not affect the quality and quantity of clean water.

So, the correct answer is 'Over grazing of livestock'.