It is difficult to place bank protection during a flood event due to the high flows and velocities, and expensive due to the cost of materials and equipment. The extensive removal of forests for crops and pastures is followed by extensive soil erosion. Wind erosion the process of detachment, transport, and deposition of soil by wind. Effects of soil erosion on soil properties as related to. Depending on the local landscape and weather conditions, erosion may be very slow or very rapid. Lisle encyclopedia of life support systems eolss arklscp ff off, 1 where a is the mass of soil lost from unit area per year, averaged over as many years as. Workshop on common criteria for risk area identification. State of play of eea work on soil erosion indicators. Soil erosion qfiles the online library of knowledge. The principal types of soil erosion by water are splash erosion, sheet erosion, interrill erosion, rill erosion, gully erosion, landslides, and stream erosion. A person shall prepare a soil erosion and sedimentation control plan for any earth change identified in r 323.
Natural erosion has sculptured landforms on the uplands and built landforms on the lowlands. Soil erosion by wind is a serious problem in the united states and the world. Erosion control in humid tropical areas like hawaii and puerto rico may present special problems. Soil erosion is the process where wind, water and human beings detach soil particles and deposit them somewhere else. Value 1 this form of erosion is no longer visible after cultivation ploughing, hoeing etc. Soil science fundamentals exam performance objectives. Erosion can also be characterized by the rates of the erosion processes, and the various factors influencing them in time and space angima et al.
Geospatial characterization and conservation potential for abr 71 subin k jose 2012 sustainable and effective management strategies are required to assess erosion at local. Splash erosion results when the force of raindrops falling on bare or sparsely vegetated soil detaches soil particles. Break up of soil clodsaggregates and dispersion of soil particles by the kinetic. Soil erosion is the displacement of the upper layer of soil, it is one form of soil degradation. Causes of soil erosion erosion occurs when farming practices are not compatible with the fact that soil can be washed away or blown away.
Sheet erosion sheet erosion is the removal of soil in thin layers by raindrop impact and shallow surface flow. Erosion, removal of surface material from earths crust, primarily soil and rock debris, and the transportation of the eroded materials by natural agencies such as water or wind from the point of removal. Types of erosion erosion is a natural process by which soil and rock material is loosened and removed. Erosion is a natural process but is often intensified by human land use practices. Wind erosion is a threat to agriculture and the earths natural resources. This natural process is caused by the dynamic activity of erosive agents, that is, water, ice glaciers, snow, air wind, plants, animals, and humans. Sheet erosion occurs when these soil particles are. Water and wind are the two main mechanisms by which soil is eroded and transported. Soil erosion occurs when soil is removed through the action of wind and water at a greater rate than it is formed soil the soil covering the surface of the earth has taken millions of years to form and we must learn to respect it. However, the percentage of these can vary, resulting in more compound types of soil such as loamy sand, sandy clay, silty clay, etc. Erosion rates are greatly accelerated during large floods and often it is too dangerous or impractical to effectively halt erosion. The plan must include the information required by rule 1703. As indicated by the classification in table 121, the texture of these soils is similar to fayette soils, but these soils differ by having a fragipan.
Symptoms of soil erosion by water may be identified by small rills and channels on the soil surface, soil deposited at the base of slopes, sediment in streams, lakes. Erosion by the action of water, wind, and ice has produced some of the most spectacular landscapes we know. Rapid erosion modeling in a western kenya watershed using. Natural erosion occurs primarily on a geologic time. Therefore, the estimation of erosion factors and exposed areas to soil erosion can be very helpful to identify the increment and the degree of the risks and, finally, to establish conservation measures and soilwater management plans. Glossary erosion and sedimentation terms adapted from washington state department of transportation publication and journal for erosion and sediment control professionals ieca abrasion removal of streambank soil as a result of sedimentladen water, ice, or debris rubbing against the bank. For better and proper crop yield, good soil conditions are necessary. Soil erosion is the process by which soil is moved. When soil is eroded, it slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Furthermore, flood risk is expected to increase with climate change and increased urbanisation, so a heavy responsibility lies with those that allocate funding and formulate flood. This can be considerable during highintensity storms. T value tolerable erosion equilibrium between soil gains and losses. Soil erosion, especially in agricultural systems, affects everyone throughout the world.
Without soil and plants the land becomes desertlike and unable to support life. Nearinfrared reflectance spectroscopy analysis of soil c and n. Sheet erosion is the more or less uniform removal of soil. Pdf assessment and reporting on soil erosion researchgate. The soil erosion site the processes of soil erosion. Four kinds of accelerated water erosion are commonly recognized.
Case studies of erosion and its causes, taking into account the effects of social. Soil and water conservation in the three gorges reservoir area of china is important, and soil erosion is a significant issue. Soil loss by water erosion may be drastically higher than in temperate regions, especially in areas of steep slopes elswaify and cooley, 1980. In the case of storage and bufferi ng, t hese consequences. Residential site soil erosion and sedimentation control. Soil can be classified into 3 primary types based on its texture sand, silt, and clay. The oakland county water resources commissioners office wrc is responsible for administering the soil erosion and sedimentation control act see soil erosion act, part 91 of pa 451 of 1994, as amended. National level soil erosion control policies in china is evidence that a single piece of legislature has many diverse effects as it has not only curbed soil erosion but also. This is a pdf file of an unedited manuscript that has been accepted. In splash erosion, falling raindrops create small craters in the soil from which soil particles are ejected.
Once this nutrientrich layer is gone, few plants will grow in the soil again. Soil erosion is a natural process that wears away the earths surface. Soil erosion soil erosion is the detachment and movement of soil material. Nationallevel soil erosion control policies in china key message. Soil science is a science that deals with the manipulation and betterment of soil conditions for the growth of plants. A case study in the denku microwatershed oromia region by kassu kebede beyene submitted in accordance with the requirement for the degree of masters in human ecology at the university of south africa supervisor. Soil particles are detached eroded, transported as sediment and deposited sedimentation by wind, water, ice or gravity. It is a naturally occurring process soil always shifts from one location to another and, under normal conditions, this shifting takes place in a slow and gradual manner. The construction of roads, parking lots, and buildings are examples of this problem. The word erosion is derived from the latin rodere meaning to gnaw, the same root that gives us the word rodent. Magnitude and the impacts of soil erosion on productivity depend on soil. Soil erosion is a natural or artificial process where the top layers of soil are blown or washed away from wind or water.
Erosion preceded by the destruction of the crumb structure due to the impact of falling raindrop on the surface of soil is termed as splash erosion. Loss of soil vegetative cover is especially widespread in developing countries. Here in thousands of areas of formerly rich limestone soil of loam, silt loam, and clay loam texture, the topsoil has been removed. China is suffering from the most serious soil erosion and degradation in the world, with 30. The book fundamentals of soil science covers the agricultural field of soil science. Soil loss is so gradual that the erosion usually goes unnoticed, but the cumulative. Processes and principles of erosion and sedimentation. Soil erosion by water can have negati ve consequences for a soil s capacity for sto rage, filtering, buffering and transformation. Unesco eolss sample chapters water interactions with energy, environment, food and agriculture vol. Helping north coast landholders reduce soil erosion. The measurement of soil loss from rills assumes that the depression forms a regular geometric shape. Dregne soil erosion is the main reason why desertification is irreversible.
The major problem associated with erosion on a construction site is the movement of soil off the site and its impact on water quality. Processes and principles of erosion and sedimentation nc. There are places and situations where erosion rates are much higher than this limit, even as high as 100 t ha. A soil erosion and sedimentation control plan must be submitted with the permit application. Although the rate of erosion from construction sites may range from 20 to 500 thayr, erosion associated with construc. In the present study, spatial markov chains were applied to explore the impacts of the regional context on soil erosion in the xiangxi river watershed, and thematic mapper remote sensing data from 1999 and 2007 were employed. The process may be natural or accelerated by human activity. Results suggest that a significant area almost 41% faces soil erosion at a rate of 022. It results in loss of the finest soil particles that contain most of the available nutrients and organic matter in the soil.
It is the fairly uniform removal of soil in thin layers from the land surface, often scarcely perceptible, especially when caused by wind. Minimum requirements for erosion and sedimentation control using best management practices. Soil erosion is the loss of soil from land due to the effects of wind and water currents. Nationallevel soil erosion control policies in china. Most soil erosion is caused by natural sources like wind and rain. Pdf on jan 1, 2003, a gobin and others published assessment and reporting on soil erosion find. Isbn 9789533074351, pdf isbn 9789535149163, published 20111021. Rill erosion occurs when water washes through the slats on a deck or patio or the eaves of your house, causing the soil underneath to form a furrowed pattern of troughs, where the water dripped down gully erosion creates minicanyons, or gullies, on bare hillside slopes where you may not have enough plants or ground cover to halt the flow of water, havent built a retaining wall, or havent.
Soil conservation and management in developing countries. The purpose of the legislation is to minimize erosion and control sedimentation to protect the water resources of the state. Flooding is a natural process, but it endangers lives and causes heavy economic loss. Vegeta tion can regenerate from a degraded state as long as the seed stock remains viable and there is soil for seeds to germinate and grow in. Brandenborg as legal notice the contents of this report do not necessarily reflect the official opinion of.
Sandy soil essentially consists of small particles formed by weathering rocks. When the layer of topsoil is removed, ground becomes unproductive and crops decrease. Excessive soil erosion and resulting sedimentation can take place during landdisturbing activities. It renders soil less productive by removing the most fertile part of the soil, namely, the clays and organic matter. The main agents of erosion are water, wind and gravity. On a construction site, the erosion process is accelerated because the soil is left bare and unprotected by vegetation. Nationallevel soil erosion control policies in china short title. Areas where loose, shallow topsoil overlies compact soil are most susceptible to sheet erosion. The role of monitoring in natural flood management.
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