GEOLOGY

Detailed explanation-1: -(b) It is important to note that all the land available for cultivation is not only used for raising food crops. Some people also live on animal rearing and, therefore, use their land for raising hay crops. Similarly, in order to restore the ecological balance of a country, some portion of land is kept under forests.

Detailed explanation-2: -Agricultural land is defined as the land area that is either arable, under permanent crops, or under permanent pastures. Arable land includes land under temporary crops such as cereals, temporary meadows for mowing or for pasture, land under market or kitchen gardens, and land temporarily fallow.

Detailed explanation-3: -These activities include sowing, increasing fertility of the soil, cutting of weed plants, moving of crops when they grow big, and harvesting.

Detailed explanation-4: -The construction of large dams and ports alters the relationship of water and land, destroying the existing ecosystem balance, hydrology and fisheries. Air and water pollution and soil erosion are the two main issues that occur when large areas on landscapes get changed for the construction of roads and railway lines.