Soil Erosion Soil Conservation Geological erosion Deforestation Accelerated erosion Over grazing Splash erosion Sheet erosion Rill erosion Gully erosion Coastal erosion Effects of soil erosion Agronomic practices Dry farming Agrostological methods Strip farming Contour farming Terrace cropping Pan breaking mulching

1. Soil Erosion & Soil
Conservation
Dr. T. Annie Sheron
Asst. Professor of Botany
Kakatiya Govt. College, Hanamkonda
Telangana

3. Learning Objectives
1. What is soil ?
2. What is soil erosion ?
3. What are the causes of soil erosion?
4. How does soil erosion takes place?
5. What are effects of soil erosion?
6. Why should we conserve soil?
7. What are the different methods of soil conservation?

4. SOIL
The upper layer of earth in which plants grow
soil is the weathered surface of the earth crust which
is mixed with organic material and in which plants
grow
Soil is a mixture of organic
matter, minerals, gases, liquids, and organisms that
together support life

5. Soil erosion
Removal of top fertile layer of soil from its original
place by agent of water, wind and glaciers.
Soil erosion is a gradual process of movement and
transport of the upper layer of soil (topsoil) by different
agents – particularly water, wind, and mass movement
– causing its deterioration in the long term.
soil erosion is the removal of the most fertile top layer
of soil through water, wind and tillage.

6. Types of soil erosion
• Geological erosion - caused by natural agencies such
as wind, water, glaciers without interference of biotic
factors
• Accelerated erosion - caused due to human
interferences such as deforestation, construction
activities etc

7. Causes of soil erosion
• Landslide
• Rain & Flood
• Cyclone
• Wind
• Tides & waves
• Water
• Forest fire
• Poor drainage system
• Deforestation
• Over grazing
• Conversion of hilly areas
to crop lands
• Various cultivation
practices

9. Landslide
A landslide is defined as the
movement of a mass of rock,
debris, or earth down a slope.
Caused by rain, earthquakes,
volcanoes, or other factors that
make the slope unstable

10. Rain & Flood
•Splash erosion
•Sheet erosion
•Rill erosion &
•Gully erosion

11. •Splash erosion/ Rain Drop Impact -
detachment of soil particles by
raindrop splash.
•Sheet erosion - Sheet erosion or sheet wash is the even
erosion of substrate along a wide area.
It occurs in a wide range of
settings such as coastal plains,
hillslopes, floodplains and
beaches.

12. •Rill erosion - removal of soil by
concentrated water flow, and it
occurs when the water forms
small channels in the soil as it
flows off site.
•Gully erosion - removal of soil
along drainage lines by surface
water runoff.

13. Soil erosion by cyclones & Floods
cyclones remove forest
canopy as well as change the
landscape near coastal areas,
by moving and reshaping sand
dunes cause extensive erosion
along the coast.

14. Soil erosion by Waves & Tides
Waves & Tides Coastal erosion is the loss or displacement of
land, or the long-term removal of sediment and rocks along
the coastline due to the action of waves, currents, tides etc.

15. Deforestation & Soil erosion
Deforestation, clear cutting or
clearing is the removal of a forest or
stand of trees from land which is
then converted to a non-forest use
Trees help the land to retain
water and topsoil.
Deforestation reduces soil cohesion
and absence of vegetation causes the
topsoil to erode more quickly.

16. Forest fire & Soil erosion
Fire changes forest ecosystems and
interacts with geomorphic processes,
climate, and landform.
Intense heat from fire cause
hydrophobicity in the soil which
accelerate the rate of water runoff.

17. Wind & Soil erosion
can be transported over great distances, sometimes across
continents and oceans.
Wind erosion affects soil quality through the loss of topsoil
rich in organic matter and can cause crop damage from
abrasion.
Wind erosion can occur when soil is
dry and loose, the surface is bare and
smooth, and the landscape has few
physical barriers to wind.

18. Various cultivation practices & Soil erosion
Tillage - fractures the soil, it disrupts
soil structure, accelerating surface runoff
and soil erosion.
Monoculture cropping - Long-term
Monoculture deteriorates organic matter
levels and soil physical properties and
lead to accelerated erosion losses and
impeded drainage.
Slash and burn agriculture

19. Effects of soil erosion
→ Water Pollution and Clogging of Waterways
→ Sedimentation and Threat to Aquatic Systems
→ Loss of Arable Land
→ Desertification
→Loss of nutrient in soil and also causes a reduction in land
productivity.
→ Loss of biodiversity
→ Air Pollution
→ Destruction of Infrastructure
→ huge losses to the economy

20. Why Preventing and Stopping Soil Erosion is so
Important
→ Soil is the backbone of our food security
→ Soils act as a pantry for plants, storing and cycling
essential nutrients and minerals that plants need to
grow
→Capture and store water for crops.
→ Reduce surface evaporation
→ Increase water use efficiency and productivity.
→Help fight and adapt to climate change by collecting and
storing carbon and reducing GHGs in the atmosphere.

21. →Allow for water infiltration through the soil, filtering
pollutants and preventing them from leaching into the
groundwater.
→Soils provide fiber, fuel, medicinal products, and other
ecosystem services.
→ Soils are home to 1/4 of biodiversity and they are a key
part of the global cycles that make all life possible.
Continued …

22. Soil conservation
Soil conservation is the prevention of loss of the top
most layer of the soil from erosion or prevention of
reduced fertility caused by over usage, acidification,
salinization or other chemical soil contamination.
OECD – “Protection of soil from erosion and other types
of deterioration, so as to maintain soil fertility and
productivity, it generally includes watershed
management and water use.”

24. Includes conservation achieved by use of plant
vegetation cover and is differentiated into
1. Agronomic practices
2. Dry farming
3. Agrostological methods.
Biological methods

25. Contour farming
Strip Cropping
Crop Rotataion
Agronomic
practices Mulching

26. Contour farming
 Oldest method of
conservation
used in areas of low rainfall
fields are prepared with
alternate ridges and furrows
 Ridges of same level
are called Contours
 Water is collected in
furrows

27. Mulching
 Mulch is a layer of material applied to
the surface of soil.
 Mulches can either be organic -grass
clippings, straw, bark chips, etc. or
inorganic - stones, brick chips, and
plastic.
 Organic mulches improves root
growth, increases the infiltration of
water, and also improves the water-
holding capacity of the soil

28. Crop Rotation
 Practice of growing a series of
different types of crops in the
same area across a sequence of
growing seasons.
Advantages : Better nitrogen management, Reduced land and
water pollution, Improved soil structure, Water conservation,
Prevention of soil erosion, Easier pest, weed control and
resistance to diseases, Climate change mitigation, Production
of green manure cover crops, Higher crop yields, Creates a
healthier environment for life

29. Strip CroppingA method of farming which
involves cultivating a field
partitioned into long, narrow
strips which are alternated in a
crop rotation system.
 Types:
→ Strip intercropping
→ Contour stripcropping
Strip cropping helps to stop soil erosion by creating natural
dams for water, helping to preserve the strength of the
soil.

30. Dry farming
Employed in places where there is
low to moderate rainfall.
To check soil erosion farmer usually
employ methods such as Crop
production, animal husbandry and
growing grazing fields.
Benefits: limited soil moisture reduces weed growth,
reduces usage of weedicide . Mulches check water
evaporation, hinder runoff and prevent erosion.

31. Ley farming
Reforestation
Retiring the land
Agrostological
methods Afforestation

32. LEY farming is a system in which
grasses and legumes are cultivated in
proper rotation for hay, silage and
pasture to meet maximum livestock
needs and improve and conserve soil
fertility.
Ley farming
Advantages:
Improves soil nitrogen content; Restores soil organic matter
structure; Controls weed growth; Prevents deep drainage and
erosion; Improves livestock efficiency; acts as Natural fertilizer.

33. Retiring the land
Areas subjected to heavy soil erosion should necessarily
be put under thick cover of grasses.
Dectylis glomerata, Eragrostis amabitis and E. cerbula are
proved to be most effective in soil binding and in
stabilizing the reserves of the bench terrace and sodding
water channels.

34. Afforestation and reforestation
Reforestation - planting
trees on land that was
previously forest.
Afforestation - refers to
planting trees on patches of
land which were not
previously covered in forest.

35. Basin listing
Contour terracing
Pan breaking
Mechanical
methods
Sub soiling
Contour trenching
Terrace outlets
Gully control
Digging of
ponds &
reservoirs
Stream bank protection

36. In this method of soil and water
conservation basins are
constructed using a special
implement called basin-lister.
These basins are constructed
across the slope. Basin listing
provides maximum time to rain
water for infiltration into the soil.
Basin listing

37. Pan breaking
Used to improve soils which are impervious to
water and are less productive
Breaking hard clay pans by means of pan breaker
on contour at a distance of about 5 feet.
Improves drainage and percolation of rain water
and soil is saved from residual run-off and erosion.

38. Sub soiling
Hard subsoil is broken deeply by sub
soiler.
 Essential in soils with hard pans to help
provide soil aeration and
improved soil drainage
Promotes absorption of rain water in the soil and
makes the soil more loose and fit to allow luxuriant
growth of vegetation.

39. Stream bank protection
Stream bank protection is the process of placing material
along a bank of a watercourse for the purpose of erosion
control to prevent the loss of bank material and property
adjacent to the banks of the watercourse
Provides bank protection and local
site protection, reduces the input
and movement of
sediment, reducing the risk of
downstream sediment
accumulation and flooding.

40. A channel is constructed along the slope to intercept
and divert the runoff water.
Channel terrace: digging channels at suitable intervals
and the excavated soil deposited as a wide, low ridge
along the lower edge of the channel.
Broad based ridge terrace: A ridge constructed along
both the sides of the channel.
Bench terrace: A number of platforms are constructed
along contours or suitable graded lines across the slope.
contour terracing :

42. Gully control
In gully control, temporary structural measures such as
woven-wire, brushwood, logs, loose stone and boulder
check dams are used to facilitate the growth of
permanent vegetative cover. Check dams are constructed
across the gully bed to stop channel and lateral erosion