Soil erosion

SOIL EROSION

  • Soil erosion is the process of detachment of soil particles from the parent body and transportation of the detached soil particles by wind and or water. The agents causing erosion are wind and water. (Click here for an animated illustration of the surface movement of water) 
  • The detaching agents are falling raindrops, channel flow and wind. The transporting agents are flowing water, rain splash and wind. Depending on the agents of erosion, it is called as water erosion or wind erosion or wave erosion.

Water erosion

  • Water erosion causes several types of damages by removing soil gradually. Sheet erosion, rill erosion, gully erosion, ravines and land slides are the types of soil losses caused by water erosion.
  • The rate of erosion depends on intensity of rainfall, slope of the land, characteristics of soil and type of vegetation.
  • The soil erosion due to rainfall in bare soil ranges from 1.9 t/ha to 16.6 t/ha, depending on the intensity of rainfall, soil type etc.
  • The water erosion is negligible in soils with plant cover.
  • Losses due to water erosion
    • Loss of rain water: Loss of rain water is through run off
    • Loss of fertile top: Loss of top soil is about 16.35 t/ha annually in India
    • Nutrient losses: Soluble forms of nutrients in the top soil is lost through run off, exchangeable and fixed forms of nutrients are lost through sediments.
    • Silting of reservoirs: Flow velocity is reduced, and sediments settles on the floor of the reservoir which reduce the depth of the reservoir

Wind erosion

  • Wind erosion is a serious problem in areas where land is bare and devoid of vegetation and is a natural phenomena in arid and semi arid zones.
  • Factors affecting wind erosion are wind velocity, temperature, rainfall, soil texture, structure, cohesiveness, bulk density, organic matter, moisture content, surface roughness, height and density of vegetative cover and type of vegetation.
  • Losses due to wind erosion
    • Loss of fertile top soil
    • Drifting of sand by wind and deposit on the good fertile land
    • Damage to crops due to abrasive action.

Wave erosion

  • Wave erosion is caused by the combined action of wind and water.
  • Wave erosion mainly occurs in rivers and canals. Lining the canals mainly controls wave erosion.
Last modified: Wednesday, 3 August 2011, 6:45 AM