INTRODUCTION, SOIL EROSION, CAUSES, TYPES AND AGENTS OF SOIL EROSION

1. INTRODUCTION
SOIL
EROSION,CAUSES,TYPES
AND
AGENTS OF SOIL
EROSION
Rishi Rajput

2. • The soil is defined as uppermost
weathered and disintegrated layer of
the earth’s crust which is comp-
osed of minerals and several organic
substances.

3. In general the depth of soil varies
from place to place,for example
some where it is to a great depth
and some where it is nil. however,
the top 30 cm soil depth is very
useful both for human being and
wildlife.

4. • The water and wind are the two
main active forces which always
tend to dislodge the top soil
layer and to transport them from
one place to another is turned as
soil erosion.

5. • Soil erosion is a three phase
phenomena, consisting the
detachment of individual soil particles
from soil mass and their transport by
erosive agents such as running water
and wind. When sufficient energy is
no longer available with erosive
agents to transport the particles, then
third phase called as ‘deposition’
taken place.

6. • The soil erosion may also be
defined as ‘detachment’ ,
‘transportation’ and
‘deposition’ of soil particles
from one place to another
under influences of wind,
water or gravity forces.

7. • The severity of soil erosion
depends upon the quantity of
material supplied by the
detachment process and the
capacity of eroding agents to
transport them.

8. • In process of soil erosion ,there
are two forms of energy are
available such as potential
energy and kinetic energy.
• The potential energy is the
result of difference in elevation
of one body with respect to
some other body, it is given as,
PE =mgh
In which PE is the potential
energy

9. m is the mass of the body,
g is acceleration due to
gravity and
h is elevation difference.

10. In case of erosion
mechanism given as
under,
KE=1/2mv2
in which v=velocity of
running water.

11. EFFECT OF SOIL
EROSION
•Loss of soil fertility and
thus affecting crop
production.
•Raising of the bed of
streams and rivers thus
reducing their capacity.

12. •Damage to
agriculture lands,
railway and roads due
to soil deposition.

13. Causes of soil
Erosion1. Destruction of natural
protective cover by
1) cutting down of trees,
2)over grazing of the
vegetative cover,
3) forest fire.

14. • Improper use of land such as
1) Keeping the land
barren subjecting to the
action of rain & wind.
2) Growing crops that
accelerate soil erosion.
3) Cultivation along land
slope.

15. Annual soil loss in different
land resources region of India
Sr
.no
LAND
RESOUR-
CES
REGION
AREA
(*1000
Km2
)
SOIL
LOSS
(t/ Km2)
Major
land
use
1 North
Himalayan
forest
region
137.7 287 forest
2 Punjab
Hariyana
Plains
101.25 330 Agri.

16. 3 Upper gangetic
alluvial plains
200.00 1440-
3320
Agri.&
waste
land
4 Lower
gangetic
alluvial plains
145.50 287-
940
Agri.
5 North easten
forest region
161.00 2780-
4095
Agri./
shiftin
g
6 Gujarat
alluvial plains
region
62.75 240-
3320
Agri.
7 Red soil region 68.00 240-
360
Agri.

17. Factor affecting soil erosion
The rainfall, runoff, wind,
soil slop, plant cover etc
are the factor which
affect the soil erosion
from particular place. All
this factors are grouped
under following three
heads.

18. • Energy
• Resistance and
• Protection
• Energy:-It includes, the
potensial ability of
rainfall, runoff and wind to
cause erosion and those
factor which directly
affect the power of erosive
agents such as wind blow
through construction of
terraces, bunds etc.

19. •Resistance:- it referred to
that group of factors,
which affect the soil
erodibility and soil
erosion. These factors
basically encourage the
infiltration rate of soil and
reduction in runoff.

20. •Protection:- this group of
factors focus on the plant
cover intercepts the
falling of raindrops before
reaching them on the
ground surface and thus
reducing their impact on
soil. The plant cover also
reduces the runoff and
wind velocities.

21. Agents of soil
erosion
• Wind and,
• Water
Types of soil erosion
• The erosion process can be
classified into two types

22. • 1) Geologic erosion
• 2) accelerated erosion
• geologic erosion refers to the
formation and loss of soil
simultaneously which maintain
the balance between formation
and various losses.
• Where as accelerated erosion
includes serious deterioration
and loss of soil by the nature
and human being.

23. • Geologic erosion :- it is a
normal process, which
represents the erosion of
soil in its natural condition.
Without influence of human
being. Geologic erosion
sometimes also known as
natural or normal erosion.
This erosion is said to be in
equilibrium with soil forming

24. surface. The geologic
erosion is long time eroding
process. Existing of stream
channels, valleys etc are the
result of geologic erosion.
2) Accelerated erosion :-
Accelerated erosion is in
excess of geologic erosion.
it is activated by nature and
man’s activity.

25. • The accelerated erosion
takes place by the action of
water, wind, gravity. In
which water causes the soil
erosion through sheet flow,
stream flow, wave action
and ground water flow.
Similarly wind detaches and
transport the soil particles
and causing a mixture of
soil at the surface.