G.INDUMATHI,M.TECH(E.E&M)-I

YEAR

CONTENTS

SOIL AND ITS COMPONENTS

SOIL EROSION AND ITS CAUSES

TYPES OF EROSIONIMPACTS

SOIL –Precious gift of Nature• It is formed by the

weathering of rocks and it covers the surface of the Earth.

• Soil is a complex mixture of organic and inorganic components and living organisms and is the main resource for food production.

SOIL EROSIONSoil erosion refers to all physical

processes that detach the particles, transport and deposit on land surface.

Much of the erosion is due to instability of land mass due to gravity and the balance is directly lost due to excessive moisture or water in the earth mass.

GEOLOGICAL EROSION-It is a long time process, involves in Soil forming and distribution and maintains Earth surface in uniform level.

NATURAL EROSION- Volcanic eruption, flood

ANIMAL AND HUMAN ACTIVITIES-Deforestation, Overgrazing, Economic Developmental activities

CAUSES OF SOIL EROSION

TYPES OF NATURAL EROSIONWATER EROSION:The separation and transport of soil through Rain, floods, melted snow(Glacial Erosion).It depends on the nature of soil, slope of the land, velocity of water.WIND EROSION:The fine loose soil particles are blown from the surface of the land and transported by the winds.Siltation-transport of soils to short distances, Suspension-tiny particles carried high and remain suspended, Surface creep-Large soil particles transported at ground level with high velocity of wind.

WIND EROSION

1.Rain drop or Splash erosion

3. Rill erosion

4. Gully erosion

2. Sheet erosion

RAIN DROP EROSION: The impact of the raindrop breaks apart the soil , once the rate of falling rain is faster than infiltration, runoff takes place.

SHEET EROSION -The thin film of water over the entire field moving down-slope.

RILL EROSION-The Collection of sheet erosion water into channels called Rills.

GULLY EROSION-The increase in size of rills forms large gully or a channel.

IMPACTS OF SOIL EROSIONOn-site effect: The loss of productivity by the loss

of valuable top soil Off-site effect : the siltation of rivers and

streams.The sediment carries agricultural chemicals

which pollutes streams and lakes-death of aquatic organisms

Reduction in Storage capacity of rivers, streams.

 

Contamination of drinking water by the Pesticide residues.

Loss and degradation of habitat from clearing grasslands and forests and draining wetland.