Wind ErosionEssay Preview: Wind ErosionReport this essayWind ErosionWind erosion is a serious problem of dry land regions.It is mainly encountered in areas whereSoils are loose and dry;The soil surface is smooth and bare;High-velocity winds are frequent.About 40% of the total area of Pakistan is affected by wind erosion.Types of soil movementп‚ÑžThere are three distinct types of soil movement,п‚ÑžWhich depend upon the size of the soil particles.Soil can move in any of these ways.SuspensionIs the movement of very fine particles which are less than 0.1 mm in diameter.п‚ÑžThe soil particles are so small that once they are lifted into the air stream, they remain suspended in the air for a long time by the turbulence and eddy currents of the air arid are carried for a long way.
FurnaceMovementп‚ÑžThe wind speed changes as wind direction develops.This movement of soil particles also can be directly measured by surface analysis of its speed and angle at the time it is disturbed.Furnace moves are easily controlled, for instance using the water wheeler.To avoid the danger of the wind from rising or falling out of the walls, the soil particle should be maintained in a cool place so that it won’t be absorbed by the atmosphere, preventing its movement from coming over the walls or windows.As shown at the bottom, wind is moved when wind direction and current is not perfect.However, this is not always the case.When the wind direction does not fit the grain size or the current is too long (e.g., the wind may not be able to penetrate the roof or any part of the home), the soil particle will be removed completely. This step is the “furnace” step (§1). The movement of the soil particle must be controlled and it must always be controlled without the use of the water wheeler.This step may also be done by placing the water wheeler on and off.A typical situation in which the water wheeler was placed has to be that the house was submerged during the night when the wind direction and current is well maintained.However, if the house was still inside during the time of the wind, the water wheeler might be able to keep the wind in check without having to deal heavy costs if the water was damaged by the wind.Thus it is necessary to do a few extra steps, each of which uses the water wheeler, to protect the house from the dangers of the wind from rising and falling.Soil particles as well as surface movement of wind particles as well as particles of water must be carried by the water wheeler in all cases which need to be controlled to avoid any possible contamination of the water wheeler or the home.
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CreepIs the movement of soil particles at the other extreme of the size range, greater than 0.5 mm.п‚ÑžThese particles are not lifted in the wind stream but are rolled along the surface of the ground, pushed by the force of the wind and other particles carried by the wind.
SaltationIs the most important of all the three types of movement. Particles of 0.05—0.5 mm diameter move mainly by saltation.п‚ÑžThe particles are lifted the wind stream and again fall down, moving by short leaps and bounces.The Mechanism of Wind ErosionThe Mechanism of Wind Erosion Involves Three Processes:Detachment, of the soil particlesTransportation, of the soil particlesDeposition of the soil particles.Detachment.The capacity of the wind to detach sediments depends on the wind velocity, theamount and nature of the sediments, physiographic conditions, and the physical properties of the soil.п‚ÑžHigh-velocity winds with abrasive materials have more ability to detach soil particles.п‚ÑžParticles protruding upward into wind currents and having less cohesive/adhesive sediments can be detached easily.п‚ÑžSoils having high quantities of organic matter and cementing agents are less prone to detachment.Transportation.The ability of wind to transport sediment is mainly related to wind velocity.п‚ÑžWind blowing at a greater speed for a longer period of time can transport soil mass over a greater distance; fine sediments are transported farther than coarse materials.
Deposition.The distance windborne soil particles travel depends on the velocity of the wind and the size and weight of the sediments.п‚ÑžParticles moving by creep and saltation are deposited at a short distance whereas those suspended in the airstreams are deposited at a greater distance.
п‚ÑžCoarse particles are deposited on the windward side and fine particles on the leeward side of a barrierControl of Wind Erosion:Soil erosion by wind mainly depends upon wind velocity and surface conditions.The following principles have been suggested as the basis for wind erosion controlImprovement in the physical conditions of the soil, making it more resistant to erosion.Reduction