Loss of fertility of soil is called:

Explanation

A fairly large area of arable land in the irrigated zones of India is becoming saline because of over-irrigation.
(i) The salt lodged in the lower profiles of the soil comes up to the surface and destroys its fertility.
(ii) Chemical fertilisers in the absence of organic manures are also harmful to the soil.
(iii) Unless the soil gets enough humus, chemicals harden it and reduce its fertility in the long run. this problem is common in all the command areas of the river valley projects, which were the first beneficiaries of the Green Revolution.
(iv) According to estimates, about half of the total land of India is under some degree of degradation.
Every year, India loses millions of tonnes of soil and its nutrients to the agents of its degradation, which adversely affects our national productivity. so, it is imperative to initiate immediate steps to reclaim and conserve soils.