Land Resources (Evs)
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Transcript of Land Resources (Evs)
LAND RESOUCES
Non-renewable resource
Essential for functioning
Supports all living beings
But is depleting day by day
LAND AS A RESOURCE
What is soil?◦ The weathered surface of earth’s crust which is
associated with living organism and the products of their decomposition.
Pedogenesis - process of soil formation The main constituent of land
SOIL
The process of breaking up of rocks into smaller particles is called weathering.
Three types of weathering:◦ Physical◦ Climate◦ Biological
WEATHERING
LAYERS OF SOIL
Red soil◦ Largest soil group◦ Rich in iron, mangnesium◦ Found in maximum parts of India.
Black soil(regur)◦ Large clay factor,without gravel◦ Contains high moisture and extrimely sticky◦ Mostly seen in central India
TYPES OF SOILS IN INDIA
Laterite soil and lateretic soil◦ Lack in fertility and low value for production◦ Contains potash,nitrogen and phosphates
Alkaline soil(reh,usar)◦ Found in drier areas◦ Mostly not suitable for cultivation◦ Imperious , thus slow drainage
Mountain and forest soils of himalayan region◦ Found in depressions of valley and slopes◦ Provides heavy growth to plants
LAND DEGRADATION
•Land degradation refers to a decline in the overall quality of soil, water or vegetation condition commonly caused by human activities.
Deforestation by fire clearence Wind erosion Water erosion Pollution including industrial wastes Poor farming practises Livestocks including overgrazing
CAUSES
Loss of quality of soil and decline in vegetation
salinity/ brackishness of land Drought Soil erosion shortage of fuelwood and building materials
in many areas.
EFFECTS
Landslides
•A landslide (or landslip) is a geological phenomenon which includes a wide range of ground movement.
•Such as downward sliding, falling, or flowing of masses of soil, rock, and debris.
Loss or absence of soil nutrients (e.g. after a wildfire)
Erosion of the toe of a slope by rivers or ocean waves
Weakening of a slope through saturation by snowmelt, glaciers melting, or heavy rains
Earthquakes
Volcanic Eruptions
Causes Of Landslides
Vibrations from Machinery or Traffic
Blast’s
Construction
Forestry Activities
Causes Of Landslides (By Human Beings)
Falls◦ Soil or Rock masses freefall from Air.◦ Generally result from undercutting by erosion.
Slides◦ Failure among one or more narrow planes.◦ Types Of Slides :
Slumps, Glide, Rockslide
Types Of Landslides
Flow◦ Caused by Internal Displacement in Soil.◦ Types Of Flow :
Earthflow Rockslide
The process by which rocks fragments and soil are detached from the original site, transported and then eventually deposited at some new locality is termed as soil erosion.
SOIL EROSION
MEANING
Normal and Geological Soil Erosion(Erosion done naturally)
Accelerated soil erosion(Loss of Soil by Man’s Activity)
KINDS OF SOIL EROSION
Water Erosion◦ Sheet erosion◦ Rill erosion◦ Gully erosion
Wind erosion◦ Saltation◦ Suspension◦ Surface creep
AGENTS OF SOIL EROSION
Landslides or slip erosion Biotic agencies cause soil erosion
◦ Overgrazing◦ Deforestation
DESERTIFICATION
The transformation of aerable or habitable land to desert,as by a change in climate or destructive land use
Viewed as both a process and the resulting condition
Is a global problem Leads to abandoned,desert like landscapes
WHAT IS IT?
Overgrazing Deforestation Overcultivation Inappropriate irrigation Drought Climate change
CAUSES
Reduced biological productivity Biodiversity loss Loss of food security Increase in soil erosion Decreasing water availablity Loss of bio-diversity
CONSEQUENCES
Afforestation Water conservation Live-stock management Wise-agriculture methods
COUNTERING DESERTIFICATION