EROSI

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EROSI
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Types of Erosion

1. Water Erosion
2. Wind Erosion
3. Gravitical erosion
4. Frozen melt Erosion

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Water Erosion
washes out seed and splashes soil into the air
Raindrops
If the fields are on a slope the soil is splashed
downhill which causes deterioration of soil
structure. Soil that has been detached by
raindrops is more easily moved than soil that has
not been detached.
Sheet erosion
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Types of Water Erosion
the uniform removal of soil in thin layers from
sloping land
Sheet erosion
the loose soil merely runs off with the rain ?
RAINDROPS
It occurs when soil is removed by water from
little streamlets that run through land with poor
surface draining.
Rill erosion
an advanced stage of rill erosion, just as rills
are often the result of sheet erosion
Gully erosion
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Sheet erosion
Rill erosion
Gully erosion
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Wind erosion
Wind erosion is the movement and deposition of
soil particles by wind
Wind erosion occurs when soils bared of
vegetation are exposed to high-velocity wind.
When its velocity overcomes the gravitational and
cohesive forces of the soil particles, wind will
move soil and carry it away in suspension
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Occurring mostly in flat, dry areas and moist
sandy soils along bodies of water, wind erosion
removes soil and natural vegetation, and causes
dryness and deterioration of soil structure.
Surface texture is the best key to wind erosion
hazard potential
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Gravitical erosion
mass movement of soil - slides, slips, slumps,
flows and landslides - gravity is the principal
force acting to move surface materials such as
soil and rock
occurs when the weight (shear stress) of the
surface material on the slope exceeds the
restraining (shear strength) ability of that
material
Factors increasing shear stress include erosion
or excavation undermining the foot of a slope,
loads of buildings or embankments, and loss of
stabilizing roots through removal of vegetation.
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Frozen-melt erosion
When water freezes, it expands suddenly and with
tremendous force
When water inside a crack in a rock freezes, its
expansive strength may be sufficient to crack the
rock and to break parts off it.