In the procedure, a winderosion equation is used to predict potential annual loss, which is converted to cropyield reduction per centimeter of erosion for wheat, grain sorghum, and corn. Erosion is a naturally occurring process, which is defined as the wearing away or disintegration of earth material by the physical forces of moving water and wind. However, their hillslope erosion component usually considers only soil erosion by water. The video defines erosion and explains why it is undesirable. The different ways soil can move during wind erosion. The user interface is used to create input files using information from user.
Weq and rweq utilize the same basic inputs, but the technology that uses. Wind erosion is widespread on agricultural land in the. Field verification was not possible as field erosion measurement equipment was not ava ilable at that time. Response of wind erosion dynamics to climate change and. This work is part of a project to better utilize long term resource monitoring program ltrmp data and scientific expertise at umesc for hrep activities. Wind erosion equation weq recent changes to weq a slide presentation download the powerpoint presentation 1. 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. Threshold wind velocity dynamics as a driver of aeolian.
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. Nevertheless, the usle equation and thus the soil erosion calculator has two main limitations that need to be considered. Assessing changes in wind erosion climatic erosivity in china. The state agronomist or erosion prediction specialist will need to set up the wind climate data, crop data and operation tillage files for many states, these. Wind erosion quantitative assessment a gis version of the revised. Soil erosion processes soil and water conservation. Pdf soil erosion by wind is a serious problem in many parts of europe and leads. Separating the climatic and anthropogenic causes of wind erosion can improve the understanding of its driving mechanisms. A gis version of the revised wind erosion equation rweq was developed in jrc to model at large scale wind erosion. Significant wind erosion occurs when strong winds blow over lighttextured soils that have been heavily grazed during periods of. The rate of soil flow varies with ridge height, degree of cloddiness of ridges, and wind velocity 1. The weq is an empirical wind erosion prediction equation that is.
Threshold wind velocity dynamics as a driver of aeolian sediment mass. Wind erosion assessment in austria using wind erosion equation and gis. 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. Processes and principles of erosion and sedimentation. Based on meteorological, remote sensing and field observation data, we applied the revised wind erosion equation rweq to simulate wind erosion in inner mongolia, china from 1990 to 2015. This cali bration of a portable wind tunnel was used to evaluate ridge roughness equivalent for many field surfaces.
An equation used for the design of wind erosion control systems. Natural erosion occurs primarily on a geologic time. The wind erosion equation is used to predict soil loss by wind forces from specific field areas. Types of erosion erosion is a natural process by which soil and rock material is loosened and removed.
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. Pollutants controlled calculation and documentation for. Npi emission estimation technique manual for mining. An introduction to the wind erosion prediction system weps. Wind erosion is a threat to agriculture and the earths natural resources. In the northern part of indiana, where sandy and organic soils are present, wind erosion is a big problem. Revised wind erosion equation rweq which estimates soil eroded and transported by wind between the soil surface and a height of two meters. The wind erosion equation the wind erosion equation weq erosion model is designed to predict longterm average annual soil losses from a field having specific characteristics. The detachment, transportation, and deposition of soil by wind. 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. Components of improved canola nitrogen use efficiency with increasing water and nitrogen tai mcclellan maaz 1, william l.
The first wind erosion equation was a simple exponen. The extent of movement depends on the amount of soil moved depends on the size of the soil particles, the cloddiness. These sources typically are characterized by nonhomogeneous surfaces impregnated with nonerodible elements particles larger than approximately 1 centimeter cm in. Components of improved canola nitrogen use efficiency with. The ridge roughness is based on ridge spacing, height, and erosive wind directions in relation to the ridge direction 5 c is the climatic factor. Soil erosion by wind in european agricultural soils. Technology currently not being used to estimate wind erosion has been incorporated into a revised wind erosion equation rweq which estimates soil eroded and transported by wind between the soil surface and a height of two meters. It is a measure of the effect of ridges formed by tillage and planting implements on wind erosion. When the force of wind is exerted on a land surface, the soil moves. Pdf wind erosion assessment in austria using wind erosion. Determining fugitive dust emissions from wind erosion. Wind erosion equation weq does not predict wind erosion where erosion is observed in some areas.
Wind erosion is simply the removal of soil particles from the surface of the land and transporting them to another location. Erosion by the action of water, wind, and ice has produced some of the most spectacular landscapes we know. Deflation is the main way wind causes erosion, it usually has a great effect on the land and it can create blowouts. It is an index of climatic erosivity, specifically wind speed and surface soil moisture. It is intended to replace the predominately empirical wind erosion equation weq. 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 steep bound.
Caesar cellular automaton evolutionary slope and river model wilsim webbased interactive landform simulation model wind erosion. Assume a smooth, level field at midland, texas, with a 1,320foot northsouth width, 25 percent of the clods greater than 0. The model calculates the metal penetration rate by erosion using an equation that accounts for sand properties, sand rate, fluid properties, flow rates, flow geometry, and material properties for the pipe. Estimation of wind erosion from construction of a railway in.
Allison member asae abstract a wind erosion equation, which estimates annual po tential erosion, requires that all vegetative cover dry weight per area be expressed as a small grain equivalent. Using the fao equation, gis and statistical analysis tools, this study quantified. Jul 30, 2016 wind erosion is controlled by reducing the wind forces on erodible soil particles or by creating aggregates on soil surfaces that are. Erosion rates under extreme conditions are provided for both water and wind erosion, giving context to the magnitude of erosion. Unlike water erosion, wind erosion is generally not related to slope gradient. Loss equation and compared our estimates with plotscale measurements and. Wind erosion equation weq colorado guidance document use of. Wind erosion prediction system weps a processbased model is now used by nrcs and weq is no longer actively supported by usda nrcs for conservation planning. 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.
Sediment delivery is the amount or fraction of soil that is actually. It is one of the processes leading to desertification. The revised wind erosion equation rweq uses mathematical equations and associated. A gis version of the revised wind erosion equation rweq was developed in jrc to model wind erosion at. The objective of this report is to compare measured erosion from 15 instrumented sites with erosion estimates using the weq and rweq models. Where wind erosion is a severe problem, such as when sand is shifting like a dune, solid plantings are advised.
A detail about the equation and its parameters are discussed in detail in this article a universal soil loss equation has been developed by the soil scientists to estimate the soil loss from any area around the globe. Mass transport q varies with soil texture, soil surface, field length, and. Wind erosion equation suggested that sediment transport could be from 57 to 212% greater for the wwcsf or ww. For years, weq has represented the most comprehensive and widely used model in the world for estimating soil loss by wind from agricultural fields. The classes of accelerated erosion that follow apply to both water and wind erosion. Assessing changes in wind erosion climatic erosivity in. It is based on the usle equation and can be applied globally. Archived wind erosion equation weq weq an empirical wind erosion prediction model was previously used and maintained by usda nrcs. Universal soil loss equation an overview sciencedirect. Revise wind erosion models more accurately portrays the physical processes of wind erosion estimates wind erosion based on wind velocity, rainfall characteristics, soil roughness, erodible fraction of soil, crusts, surface residues and other dynamic factors.
Soil characteristics and associated wind erosion potential altered. Wind erosion weps soil erosion by wind is a serious problem in the united states and the world. There is a need for more information about wind erosion than just rotational average tonsacreyear we get now. The factor for any given location is based on longterm climatic data and is expressed as a percentage of the c factor for garden city, ks, which has been assigned a value. For the sahelian region, extended weather data files are. Processes and effect on soil productivity leon lyles member asae abstract part one concerns basics of the erosion process in terms of particle dynamics, threshold condi tions, particle flux, and the protective role of nonerodible elements. However, the evaluation of the constants in the equation for wind erosion is comparatively difficult than the universal soil loss equation. Correction factors were developed only for the 17 field crops. 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. The hazard of wind erosion is increased by removing or reducing the vegetation.
To copy the needed data from the above file, open the weq master file weqvs8. E the predicted average annual soil loss in tons per acre per year. Also, planners will need to have a basic understanding of the wind erosion equation weq, understand irrigation where the land is irrigated, and have basic excel spreadsheet skills. Response of wind erosion dynamics to climate change and human. An overview of the wind erosion prediction system introduction soil erosion by wind is a serious problem in the united states and the world. These correction factors were developed for specific soil textures, crop types, and geographic locations and then applied to the wind erosion estimates developed from the wind tunnel studies. Locate the windparm data for your state and manually copy this data. Planting windbreaks will usually help control wind erosion. The wind erosion equation was developed by the late dr. This manual may be reproduced in whole or part for study or training purposes subject to the inclusion of an acknowledgment of the source. Land susceptibility to water and wind erosion risks in the east africa. The spps erosion model and computer program were developed by the university of tulsa ecrc program 5,6. Wind erosion 1 wind erosion in regions of low rainfall, can be widespread, especially during periods of drought.
Pdf an introduction to the wind erosion prediction system weps. Wind is effective in causing erosion in deserts because the sand isnt held in place by vegetation and blows easily. Herricka a usdaars jornada experimental range, msc 3 jer, nmsu, box 30003, las cruces, nm 88003, usa busdaars wind erosion and water conservation research unit, 3810 4th street, lubbock, tx 79415, usa article info. National minimum criteria pertaining to erosion and sediment control under an rms. The following soil erosion calculator is a tool to calculate the average annual rate of erosion. Wind erosion can be a threat to agriculture productivity and the sustainability of the earths natural resources.
Application of wind fetch and wave models for habitat. It renders soil less productive by removing the most fertile part of the soil, namely, the clays and organic matter. A stateoftheart wind erosion simulation model, the wind erosion prediction system and the united states environmental protection agencys ap 42 emission factors formula, were combined together to evaluate wind blown dust emissions from various construction units from a railway construction project in the dry gobi land in northwest china. Part two is a procedure for evaluating wind erosion effects on soil loss and, subsequently, on crop yields. We used the variable control method by input of the average climate conditions to calculate humaninduced wind erosion. Wind erosion equation weq does not predict wind erosion where erosion. It is the result of nearly 30 years of research to determine the primary variables or factors that influence erosion of soil by wind. In the past, wind erosion losses have been estimated by the wind erosion equation7. Wind erosion climatic erosivity is a measure of climatic factors influencing wind erosion, therefore, evaluation of its intensity and response to recent climate changes can contribute to the understanding of climate change effect on wind erosion risk. The erosion of surface soil by wind renders the soil less productive by removing the most fertile part of the soil, namely. It is a dynamic, physical process where loose, dry, bare soils are transported by strong winds.
Modeling and predicting wind erosion wind erosion equation weq from the weps 1. Soil erosion soil loss wind erosion universal soil loss equation revise universal soil loss equation. Wind erosion assessment in austria using wind erosion. The rela tionship between soil flow and ridge height, within pre scribed limits, follows an approximate catenary curve. 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. It embodies the fundamental concept described by ellison in 1947 that ero sion is a process of detachment and transport. This report presents the first quantitative measurements of wind erosion activity during the 1940s and 2000s and interprets these trends in the light of changes in land management. The model is designed to predict the daily soil loss potential by wind erosion at 1km spatial resolution. An introduction to the wind erosion prediction system weps john tatarko, soil scientist usdaars, wind erosion research unit, manhattan, ks larry wagner, agricultural engineer usdaars, wind erosion research unit, manhattan, ks written for presentation at the 2007 asabe annual international meeting sponsored by asabe. E f ikclv wherein e is the average annual soil loss, expressed in tons per acre per year. Soil cohesion depends strongly on the consistence, packing, and saturation condition.
An equation in the form of universal soil loss equation has been developed and can be used for estimating soil loss by wind. Equivalent wind erosion protection from selected crop residues leon lyles, bruce e. The usle has been used in more than 100 countries to guide conservation planning, assess soil erosion for conservation. Natural erosion occurs primarily on a geologic time scale, but when mans activities alter the landscape, the.
Land degradation by water and wind erosion is a serious problem worldwide. Water erosion is very simplistically speaking caused by rainfall, river flow, waves wave action, hydraulic action and abrasion, corrosion, glacier movement, thawing, etc. There is a need for an easier to use and a faster model. The revised wind erosion equation rweq poorly predicted maximum mass transport and so spatial. Wind erosion is a common cause of land degradation in the arid and semi arid grazing lands of inland queensland.
With appropriate selection of factor values, the equation will estimate average annual erosion or erosion for specific time periods. Over 10 million scientific documents at your fingertips. C factorwind erosion climatic factor in wind erosion equation weq. Modeling water and wind erosion is important to understanding the processes. Wind erosion and land management in australia during 1940. The equation uses the values of parameters of the factors that affect the soil erosion. The wind erosion equation was derived in laboratory wind tunnels from measurement of basic physical processes in the 1960s. The universal soil loss equation usle is hailed as one of the most. 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. The erosion component of an rms addresses sheet and rill erosion, wind erosion, concentrated flow, streambank erosion, soil mass movements, road bank erosion, construction site erosion, and irrigationinduced erosion.
The reduction in wind erosion caused by vegetation can be seen as the physical amount of wpsf service and represents the difference between the potential wind erosion amount under bare soil conditions and the actual wind erosion amount under vegetation conditions, which can be calculated based on rweq model 29, 31. Wepp is a computer model for predicting soil erosion and sediment delivery from fields, farms, forests, rangelands, construction sites and urban areas. It is a measure of the erosive potential of the wind speed and surface moisture at a given location compared with the same factors at garden city, kansas. This nebguide discusses how wind erosion occurs and presents methods for reducing wind erosion on land devoted to crop production. Wind erosion modelling in a sahelian environment utrecht. The factor for any given location is based on longterm climatic data and is expressed as a. Wind erosion equation weq colorado guidance document use of microsoft excel spreadsheet model p. Wind erosion refers to the detachment, transport, and deposition of sediment by wind. Usle was the first empirical erosion equation that was not tied to a specific region of the united states, thus the title universal soil loss equation. The heart of any wind erosion model is the equation for computing the mass transport of wind eroded material. In earth science, erosion is the action of surface processes such as water flow or wind that removes soil, rock, or dissolved material from one location on the earths crust, and then transports it to another location not to be confused with weathering which involves no movement. Revised wind erosion equation rweq is adopted to calculate the amount of sand fixed and sand fixing rate and such factors as wind speed, rain precipitation, temperature, soil texture, terrain and vegetation cover are mainly considered during assessment of soil erosion and water and soil conservation. Lyon, extension dryland crops specialist, and john a. The universal soil loss equation usle wischmeier and smith 1978 and wind erosion equation weq woodruff and siddoway 1965 enabled estimation of changes in sheet and rill erosion and wind erosion.