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Control Wind Erosion

 The basic principles in the control of wind erosion are breaking of wind velocity at the soil-atmosphere interface and the reduction in soil erodibility. A suitable surface soil texture is the best key to wind erosion protection. Properly managed crop residues carefully timed soil tillage, and accurately placed crop strips and crop barriers can all effectively reduce wind erosion. Proper land use and adaptation of adequate moisture conservation practices are the main tools that help in wind erosion control. Three basic methods can be used to control wind erosion: 1. Maintain Vegetative Cover (Vegetative Measures) 2. Roughen the Soil Surface by Tillage Practices (Tillage Practices or may be called Tillage Measures) 3. Mechanical or Structural Measures (Mechanical Measures) 1. Vegetative Measures  Vegetative measures can be used to roughen the whole surface and prevent any soil movement. The aim is to keep the soil rough and ridged to either prevent any movement initially or to qui...
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Wind erosion

 It is the detachment and transportation of soil particles by the forces generated by wind. Occurs on all types of soil but fine single grain particles are most susceptible. Wind erosion, in India, is commonly observed in arid and semi-arid areas where the precipitation is inadequate, e.g. Rajasthan and some parts of Gujarat, Punjab, and Haryana. About 13.5 Mha area representing 4.1% of TGA of the country is affected by wind erosion. Mechanisms of Wind Erosion Wind erosion means detachment and transportation of soil particles by the forces generated by wind. The intensity of wind erosion varies with surface roughness, slope, and types of cover on the soil surface and wind velocity, duration, and angle of incidence. It can occur on all types of soil but fine single grain particles are most susceptible. The wind erosion process can be divided into three simple but distinct phases, 1. Initiation of Movement/Detachment: The lifting and abrasive action of the wind results in the detachm...
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Gully Erosion

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 Gully erosion is an advanced stage of rill erosion. It is a process where surface (or subsurface) water concentrates in narrow flow paths and removes the soil resulting in incised channels that are too large to be destroyed by normal tillage operations. Although gully erosion is a natural process, it is most often triggered or accelerated by human activities such as clearing vegetation and overstocking. The gully development is recognized in four stages:  Formation Stage: Scouring of topsoil in the direction of general slope occurs as the runoff water concentrates. It normally proceeds slowly where the topsoil is fairly resistant to erosion.  Development Stage: Causes upstream movement of the gully head and enlargement of the gully in width and depth. The gully cuts to the C-horizon of soil, and the parent materials are removed rapidly as water flows.  Healing Stage: Vegetation starts growing in the gully.  Stabilization Stage: Gully reaches a stable gradient, gully walls atta...
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Agronomical Measures of Water Erosion Control

 In soil and water conservation, the agronomical measure is a more economical, long-lasting, and effective technique. Agronomic conservation measures function by reducing the impact of raindrops through interception and thus reducing soil erosion. They also increase infiltration rates and thereby reduce surface runoff. Widely used agronomic measures for water erosion control are listed below. Contour Cropping: Contour Cropping is a conservation farming method that is used on slopes to control soil losses due to water erosion. Contour cropping involves planting crops across the slope instead of up and down the slope. Cover crops: Close growing crops such as grass, legumes, or small grains. Strip Cropping The practice of growing protective crops and row crops in alternate strips on the contours. Vegetative barriers: Also called buffer strip cropping on steep slopes. Mulching Mulches are used to minimize rain splash, reduce evaporation, control weeds, reduce the temperature of the soi...
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Mechanics of Water Erosion

 There are three steps for accelerated erosion by water: i) Detachment or loosening of soil particles caused by flowing water, freezing and thawing of the topsoil, and/or the impact of falling raindrops. Rain splash is the most important detaching agent. ii) Transportation of soil particles by floating, rolling, dragging, and/or splashing and iii) Deposition of transported particles at some places of lower elevation. Types of Water Erosion Water erosion can be classified as splash erosion, sheet erosion, rill erosion, gully erosion, stream bank erosion, sea-shore erosion, and landslide erosion. They are discussed as follows. 1. Splash Erosion: A falling raindrop is capable of generating a force equals to almost 14 times its weight. It is also known as raindrop erosion because it is caused by the impact of raindrops on the exposed soil surface. Most important detaching agent. A raindrop produces three important effects during splash erosion, i) beating action breaks down soil aggreg...
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Water Erosion

 It is the removal of soil from the land surface by water, including runoff from melted snow and ice and is one of the major causes of soil degradation. Water erosion has been sub-divided into various types in relation to the progressive concentration of surface runoff. Erosion of soil by water is caused by its two forms: liquid as the flowing water, and solid as the glaciers. Forms of Water Erosion The impact of rainfall causes splash erosion. Runoff water causes scraping and transport of soil particles leading to sheet, rill, and gully erosion. Water waves cause erosion of the banks' sides of reservoirs, lakes, and oceans. The subsurface runoff causes soil erosion in the form of pipe erosion, which is also called tunnel erosion. The glacial erosion causes heavy landslides. In India, glacial erosions are mainly confined to the Himalayan regions. The various forms of water erosion are given below. 1. Hydraulic Action: The hydraulic action takes place when water runs over the soil s...
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Soil Erosion and It's Types

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 The word erosion has been derived from the Latin word „erodere‟ which means eating away or to excavate. The word erosion was first used in geology for describing the term hollow created by water. Soil Erosion is defined as the detachment of soil particles, their transportation from one place to another, and deposition elsewhere through water, wind, coastal waves, snow, gravity, and other forces. It is a two-phase process involving the detachment of individual soil particles from soil mass, transporting it from one place to another (by the action of any one of the agents of erosion, viz; water, wind, ice, or gravity) and its deposition. When sufficient energy is not available to transport a particle, a third phase known as deposition occurs. In general, finer soil particles get eroded more easily than coarse particles (silt is more easily eroded than sand). Major erosive agents are impacting raindrops and runoff water flowing over the soil surface. Types of Soil Erosion According t...
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