Soil Erosion

DONE BY POORNIMA S

AEC & RI,KUMULUR.

• Definition: Loss of soil.

• Latin word :

‘erodere’ – to eat away /to excavate.

Problems caused by erosion:

• Damage to sea coast and formation of sand dunes.

• Diseases and public health hazards.

• Spent of money on water purification works.

• Siltation of irrigation channels, rivers & reservoirs.

• Problems in crop irrigation & consequent need of conserving the

water.

• Main active factors : Water & Wind.

• Three phase phenomenon:

1. Detachment

2. Transportation by erosion agents.

3. Deposition.

• Two forms of energy:

1. Potential energy : PE = m.gh (joules)

2. Kinetic energy : KE = ½ MV² (joules)

• Erosion may be broadly classified into two groups:

1. Geological erosion

• Natural/normal erosion

• Without influence of human.

• Agents: Water, wind, gravity and glaciers.

• Loss of soil = formation of new soil.

2. Accelerated erosion/Abnormal erosion:

• Influence of human activities.

• Equlibrium b/w soil building & soil removal is disturbed.

• Removal of surface soil takes much faster than soil forming process.

• Agents : Water & Wind (Primary agent)

• It is classified into

1. Water erosion

2. Wind erosion.

• In India : (Total geographical area – 326 million hec. of land ; Eroded

area – 81 million hec.)

Factors responsible for soil erosion:

Excessive deforestation Over grazing

Faulty agril. Practices

Evil effects of erosion:

1. Loss of productive or fertile soil.

2. Deposition of sand on productive land

3. Silting of lakes & reservoirs

4. Water scarcity

5. Fragmentation of land.