Question

Q26. What happens when excessive fertilisers are washed away into
water bodies? Explain.
(2mark) (5 min)​

Answer 1

Answer:

When manure or commercial fertilizers enter surface water, the nutrients they release stimulate microorganism growth. The growth and reproduction of microorganisms reduce the dissolved oxygen content of the water body. Without sufficient dissolved oxygen in surface water, fish and other aquatic species suffocate.

Excessive quantities of chemicals (fertilizers, weedicides,insecticides, pesticides etc.) get washed away from the fields entering into water bodies like ponds,rivers,sea. These act as nutrients for algae to flourish. Once these algae die, they serve as food for decomposers like bacteria.

Answer 2

that highlight word is important

this is from my answer book hope it helped you

☺️