Difine: Soil pollution Soil eroision Percolation.

Soil Erosion: Removal of topsoil by weathering agents; such as wind, water and ice is known as soil erosion. Soil erosion affects the fertility of soil, as humus present in the soil is eroded along with soil. It is important to prevent soil erosion.

Soil Pollutions – The soil is an essential nutrient for the existence of plants and for agriculture. It is very important for maintaining an ecological balance in nature and keeping our environment green. But with the current trend of increasing population, there is a consequent increase in demand for land and other resources.

Percolation Rate of Water: Amount of water drained through water in unit time is known as percolation rate of water in soil. Percolation rate of water can be calculated using the formula given here.

Percolation rate (mL/min) = Amount of water in mL/Time taken to percolate

The percolation rate of water in sandy soil is fastest and in clayey soil is slowest.