It is found that the fences porosity is the key factor that determines the resulting shelter effect. Computer solution and application1 abstract because of the many tables and figures required to solve a wind erosion equation was programmed for computer solu tion. As of today we have 78,789,783 ebooks for you to download for free. Explain how physical and chemical weathering lead to erosion and the formation of soils and sediments. It renders soil less productive by removing the most fertile part of the soil, namely, the clays and organic matter. I20, big spring, tx 79720, usa b usdaars wind erosion and water conservation research unit, 3810 4th street, lubbock, tx 79415, usa. While the universal soil loss equation usle uses rainfall as an indicator of erosive energy, musle uses the amount of runoff to simulate erosion and sediment yield. Erosion rates under extreme conditions are provided for both water and wind erosion, giving context to the magnitude of erosion. The environmental policy integrated climate model epic has been used to evaluate policy effects on soil erosion. Wind blows loose soil off flat or sloping land known as wind erosion. The universal soil loss equation usle predicts the longterm average annual rate of erosion on a field slope based on rainfall pattern, soil type, topography, crop system and management practices. Some models focus on longterm natural or geological erosion, as a component of landscape evolution.
Lyon, extension dryland crops specialist, and john a. Wind erosion equation weq recent changes to weq a slide presentation download the powerpoint presentation 1. Validation of the wind erosion stochastic simulator wess. If you do not have the acrobat reader on your computer you can download it from the adobe web site by clicking the icon below. The c value, however, does not closely relate to precipitation, which implies that precipitation in tazhong plays a less important role on. This cali bration of a portable wind tunnel was used to evaluate ridge roughness equivalent for many field surfaces. Response of wind erosion dynamics to climate change and. Porous fence is a kind of artificial windbreak that has many practical applications. These factors are placed in the equation in such a manner that condition of a place like climate, slope of land, crop management, rainfall, temperature and conservation practices are also accounted to get realistic estimates from the universal soil loss. These actions depend mainly on the type of soil, the climate, the vegetation cover, the speed and frequency of wind.
Rusle2 is an upgrade of the textbased rusle dos version 1. It is a dynamic, physical process where loose, dry, bare soils are transported by strong winds. An overview of the wind erosion prediction system introduction soil erosion by wind is a serious problem in the united states and the world. Wind erosion is controlled by reducing the wind forces on erodible soil particles or by creating aggregates on soil surfaces that are. Usle only predicts the amount of soil loss that results from sheet or rill erosion on a single slope and does not account for additional soil. It involves detachment, transport, sorting, abrasion, avalanching, and deposition of soil. Download acrobat pdf file 3mb supplementary material.
A wind erosion equation is an equation used to design wind erosion control systems, which considers soil erodibility, soil roughness, climate, the unsheltered distance across a field, and the vegetative cover on the ground references this article incorporates public domain material from the congressional research service document. Spatiotemporal pattern of wind erosion on unprotected. The surface land area affected by soil wasting due to erosion is calculated at 1100 mha through rainwater erosion and 550 mha by wind erosion sammi reddy, singh. However, the evaluation of the constants in the equation for wind erosion is comparatively difficult than the universal soil loss equation. It is one of the processes leading to desertification. Universal soil loss equation an overview sciencedirect. Processes and principles of erosion and sedimentation. The equation uses the values of parameters of the factors that affect the soil erosion. Wind erosion wind erosion is the detachment and movement of soil particles by air moving at least 20km per hour. Soil erosion processes soil and water conservation. The results showed a strong spatiotemporal heterogeneity of weutrs. Wind erosion assessment in austria using wind erosion. Evaluation of soil loss estimation using the rusle model. A wind erosion equation, soil science society of america proceedings, vol.
Data should be consistent with the construction permit for the facility. It is a computer model containing both empirical and processbased science in a windows environment that predicts rill and interrill erosion by rainfall and runoff. Universal soil loss equation and revised universal soil loss equation 9 include any impact either erosion or deposition of the concentrated flow channels that form in the natural swales at the bottom of the roughly planar hillslopes, and certainly did not address classical gullying processes that often occur at. There are various methods of biological and physical methods to control wind erosion, including windbreakers, maintaining vegetation residues on the soil surface, utilizing stable soil aggregates or clods, reducing field width. The rweq revised wind erosion equation was reported in 1998 by fryrear et. Users will not need to download the files below, when the date match the date of the files in the users folder for items 3, 6. Validation of the wind erosion equation weq for discrete. Erosion and sediment yield in swat are estimated of each hru with the modified universal soil loss equation musle developed by wischmeier and smith 1965. The threshold wind velocities at different distances downwind from porous fences were measured and the corresponding characteristics of particle movement observed to assess their shelter effect. The kinematic runoff and erosion model kineros is an eventoriented, physically based model describing the processes of interception, infiltration, surface runoff, and erosion from. It is the result of nearly 30 years of research to determine the primary variables or factors that influence erosion of soil by wind. Weaknesses,in the equation,and,areas needing,further research are discussed.
Sometimes water flows as a sheet over large areas down a slope. The relationships among variables are evaluated by the computer, and the. Wind erosion refers to the detachment, transport, and deposition of sediment by wind. Revised universal soil loss equation rusle2 and wind erosion prediction system weps instructions for downloading the most current files and databases for conservation planners. Its value becomes higher when wind speed increases. Wind erosion is widespread on agricultural land in the. Types of erosion erosion is a natural process by which soil and rock material is loosened and removed. Wind erosion is a common cause of land degradation in the arid and semi arid grazing lands of inland queensland. Blowing soil or soil erosion by wind is a complex process.
Section2 wind erosion and deposition agents of erosion and deposition name class date chapter 3 after you read this section, you should be able to answer these questions. The wind erosion equation was developed by the late dr. Suspension occurs when the wind lifts finer particles into the air leading to dust storms. Hence, in development of the wind erosion equation woodruff and siddoway, 1965. The weutrs was calculated by the revised wind erosion equation with meteorological data 19882017 and raster data of soil properties. Erosion by the action of water, wind, and ice has produced some of the most spectacular landscapes we know. The wind erosion equation is used to predict soil loss by wind forces from specific field areas. The first wind erosion equation was a simple exponen. The video defines erosion and explains why it is undesirable.
Based on meteorological, remote sensing and field observation data, we applied the revised wind erosion equation rweq to simulate wind erosion. There is a need for an easier to use and a faster model. Method factsheet rusle revised universal soil loss equation introduction the revised universal soil loss equation rusle is an empirical erosion model recognised as a standard. For other formats, simply clic k the appropriate hyperlink. Limitations of the wind erosion equation the factors in the weq often interact with each other and therefore it requires complex equations and tables however these do not accurately account for the complex interactions affecting wind erosion therefore the nrcs developed revised weq and an excel spreadsheet website containing rweq. Wind moves the soil in two ways, suspension and saltation.
Explain how waves, wind, water, and glacial movement shape and reshape the land surface of the earth by eroding rock in some areas and depositing sediments in other areas. Method factsheet rusle revised universal soil loss. Wind erosion equation weq does not predict wind erosion where erosion is observed in some areas. Wind erosion assessment in austria using wind erosion equation and gis andreas klik boku university of natural resources and applied life sciences vienna muthgasse 18. Wind erosion is described in more detail, including the three types of sediment transport in wind erosion, along with an explanation for how wind erosion. However, many erosion models were developed to quantify the effects of accelerated soil erosion i. Natural erosion occurs primarily on a geologic time. Users will not need to download the files below, when the date match the date of the files. Zobeck b a usdaars wind erosion and water conservation research unit, 302 w. The various components of rweq were developed from controlled laboratory and field studies, but the actual transport model was calibrated using field data of. Evaluation of soil loss estimation using the rusle model and scscn method in hillslope mining areas. C r o p s e r i e s soil controlling soil erosion from wind no. Department of agriculture, agricultural research service, ars77, pp. This information is provided by the usda engineering and wind erosion research unit in.
Vegetative barriers reduce erosion from wind by reducing. Significant wind erosion occurs when strong winds blow over lighttextured soils that have been heavily grazed during periods of. This video will help you better understand the problems associated with wind erosion of soil. Separating the climatic and anthropogenic causes of wind erosion can improve the understanding of its driving mechanisms. Wind erosion is a threat to agriculture and the earths natural resources. Rweq incorporated advances in wind erosion science after 1965. This nebguide discusses how wind erosion occurs and presents methods for reducing wind erosion on land devoted to crop production. Saltation occurs when the wind lifts larger particles. Wind erosion wind erosion is the form of soil degradation by the action of the wind which abrades, transports and deposes soil sand particles. Validation of the wind erosion equation weq for discrete periods r. An equation in the form of universal soil loss equation has been developed and can be used for estimating soil loss by wind.896 77 822 1201 32 318 1150 1078 153 790 611 1385 280 281 214 1145 453 1455 1370 1365 702 209 1062 793 812 734 1088 388 195 1159 944