NEET BIOLOGY

Detailed explanation-1: -Gradually, the fertile land gets converted into deserts. This is called desertification. Hence, ‘deforestation can lead to desertification’.

Detailed explanation-2: -The given statement is false. Deforestation causes a decrease in water holding capacity which results in soil erosion and floods. This happens due to the removal of plants, as plant roots hold water and prevent soil erosion and floods.

Detailed explanation-3: -Human activities that contribute to desertification include the expansion and intensive use of agricultural lands, poor irrigation practices, deforestation, and overgrazing. These unsustainable land uses place enormous pressure on the land by altering its soil chemistry and hydrology.

Detailed explanation-4: -’Climatic variations’ and ‘Human activities’ can be regarded as the two main causes of desertification. removal of the natural vegetation coverby taking too much fuel wood, agricultural activities in the vulnerable ecosystems of arid and semi-arid areas, which are thus strained beyond their capacity.

Detailed explanation-5: -Deforestation reduces biodiversity by disrupting the hydrologic cycle, destroying habitat, causing soil erosion, and, in extreme cases, can lead to desertification. Thus, the loss of biodiversity does not cause deforestation. Thus, statement 4 is incorrect.