Soil conservation is the:

Explanation

Soil conservation is to conserve fertile soil from losses like heavy rainfall, drainage, high wind, flood, drought etc. Soil is the top cover of the Earth in which plants can grow. The rotation of crops, contour ploughing and use of proper fertilizers help in maintaining the fertility of the soil. Plantation of trees, controlled grazing of grasslands, reforestation and prevention of forests fires will protect the erosion of topsoil. The regulation of water resources to prevent floods will help not only in soil conservation but will also supply an adequate water supply in periods of drought.