Question

the use of manure and biofertilizers should be preferred over use of chemical fertilizers.why?​

Answer 1

The use of chemical fertilizers on crops can have adverse effects on waterways caused by chemical run off of the excess fertilizer. The over-abundance of nutrients in the water reduces the amount of oxygen. The existing organisms living in the water use up the oxygen that is left.

Unlike these fertilizers, organic manures improve soil quality and promote crop growth. These manures also have a number of other benefits. Organic manures provide nutrients that are important for growth of plants. They act slower and are gentler as compared to chemical fertilizers.

Answer 2

Chemical fertilizers are non-biodegradable which will be washed out by rain to nearby water bodies. The aquatic animals in the lake may consume those fertilizer and in turn, we consume those fishes. Thus, by bio magnification the fertilizer enter our body and cause harm.

Thus, manure and bio fertilizers should be preferred as they are bio-degradable and does not cause any harm to the ecosystem.