EDUCATION (CBSE/UGC NET)

Detailed explanation-1: -Answer. Explanation: B) DEFORESTATION-Deforestation, which involves the removal of large areas of forests, can lead to decreased soil fertility by exposing the soil to erosion and reducing the amount of organic matter in the soil.

Detailed explanation-2: -Deforestation leads to a decrease in the water holding capacity of the soil. The movement of water from the soil surface into the ground (infiltration rate) is reduced. So, there are floods which washes away the topsoil along with nutrients.

Detailed explanation-3: -Leaching removes vital nutrients and micronutrients, such as water-soluble boron, from the soil, causing potential deficiencies in crops. For example, when crops suffer from boron deficiency, they exhibit visual symptoms including: Misshapen, thick, brittle, small leaves.

Detailed explanation-4: -Soil fertility decline occurs when the quantities of nutrients removed from the soil in harvested products exceed the quantities of nutrients being applied. In this situation, the nutrient requirements of the crop are met from soil reserves until these reserves cannot meet crop demands.

Detailed explanation-5: -Soil nutrient loss through runoff and sediment, is a major driver for soil fertility decline [1, 2]. The eroded sediments or soil are highly concentrated with crop nutrients, which are washed away from farmlands.