Physical geography a small channel or gulley, such as one formed during soil erosion. Equations for terrace spacing have been developed based on field experience. Soil quality information sheet rangeland soil quality. Prediction of sheet and rill erosion over the australian. If the wind is dusty, or water or glacial ice is muddy, erosion is taking place. Partitioning the contributions of sheet and rill erosion. The shear stress of flow in rills helps determine detachment capacity and transport capacity of flow. An understanding of the relative contributions of sheet and rill erosion to the total soil loss associated with individual events and of changes in their relative importance during an event is important for. General principles for erosion prevention and sediment control at construction sites in minnesota metadata this file contains additional information, probably added from the digital camera or scanner. The rate of erosion may be very slow to very rapid, depending on the soil, the local landscape, and weather conditions.
Soil loss by water erosion initiated by sheet and rill erosion in europe is 0. Soil erosion sheet, rill and wind erosion detachment and transportation of soil particles caused by rainfall runoffsplash, irrigation runoff, or wind that degrades soil quality. Soil atlas of europe map showing the risk of water erosion in the 27 member states of the european union fact. Soil erosion soil erosion is the loosening and displacement of topsoil from the land due to the action of agents like wind and water. Erosion is not always readily visible, even when soil loss exceeds unsustainable. Quantification of rill erosion using field measurements. Pdf rills are frequently observed on slope farmlands and rill erosion significantly contributes to sediment yields. Institute, celestijnenlaan 200 e, 3001 heverlee, belgium. Soil erosion in nature may be a slow process geological erosion or a fast process promoted by human activities like overgrazing, deforestation.
The characteristics of rill development and their effects. Gully erosion may cause considerable soil losses and produce. Terraces are spaced to avoid excessive rill erosion. Certified crop advisor study resources northeast region. Smith, craig busskohl, the editor and assistant editor, and three. It happens when water from rainfall does not soak into the soil, but runs across it instead. A view of rill 1 and gully 2 in the study area in this study by using field surveying and many observations, measurements of gullies, rills, and pedestals were. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Distribution of earths waters location of storage total water acrefeet % of total % of fresh water residence time years total water on earth 1.
Sheet and rill erosion olivier cerdan physical and regional geography research group, katholieke universiteit leuven, geo. Factors affecting sheet and rill erosion smith 1957. Weathering and erosion lead to the simultaneous process of degradation and aggradation. Rill erosion is the detachment of soil particles by surface flow, and it occurs in a series of rills, which are small, parallel channels a few tens of. A basin wide estimation at hillslope to medium catchment scale hua lu, chris j. The rain detaches the soil particles, splashes them. Most erosion is performed by liquid water, wind, or ice usually in the form of a glacier. Rill erosion was found to be nonselective, while for interrill erosion the enrichment ratio of oc, er oc, varied between 0. Application of gully and rill erosion indicators for. Estimating sheet and rill erosion the revised universal soil loss equation version 2 rusle2 is used to estimate interrill sheet and rill erosion caused by water. Gully erosion gullies are channels deeper than 30cm that cannot. Csiro land and water sheet and rill erosion and sediment delivery to streams.
Prosser, chris moran, graeme priestley csiro land and water. Interrill erosion is defined as soil movement that occurs when raindrops strike exposed soil. Rill erosion is a type of erosion that results in small, yet well defined streams. An experimental study of rill erosion and morphology. Rill formation is the predominant erosion process in slope land in the loess plateau, china. The most prominent erosion features in the studied area are rill and gullies, therefore in the next sections only these indicators will be described fig. Rill erosion is the formation of small, generally parallel channels formed by runoff water. The relative effectiveness of each of the three main conservation practices in control of erosion, contour farming, strip cropping, and terracing is presented. Using field rillometer measurements of rills as input into the. Predicting sheet and rill erosion of shihmen reservoir.
Rill erosion is the most obvious mechanism of soil loss from sloping, cultivated land fig. Taken in 2014 submitted on 10 november 2014 categories. Rill erosion can be reduced by reducing the volume and speed of surface water with grassed waterways and filter strips, ripped mulch lines, and contour drains. Rill erosion in natural and disturbed forests moscow forestry. The rill model equations were solved for increasingly complex cases of spatial and temporal variabilities.
A model which used rill measurements as input, was used to determine the rill plan areas, rill volumes, and thus rill erosion rates in the test area. Processes and principles of erosion and sedimentation. Towards an assessment of the ephemeral gully erosion. Prediction of sheet and rill erosion over the australian continent, incorporating monthly soil loss distribution hua lu, john gallant, ian p. The rills or small channels often only 30cm deep are caused when water running across the surface of the ground gathers in a natural depression in the soil, and erosion. Splash erosion results when the force of raindrops falling on bare or sparsely vegetated soil detaches soil particles. Usle universal soil loss equation the universal soil loss equation for construction sites excel worksheet was developed by dane county water resource engineering to estimate soil loss from. The input variables for soil loss calculations include climate, soil texture, topography and soil cover.
Shihmen reservoir watershed is vital to the water supply in northern taiwan but the reservoir has been heavily impacted by sedimentation and soil erosion since 1964. Understanding the factors influencing rill erosion on. The erosion created by these forces increases the size of the rill while also swelling its output volume. With regard to environmental impacts, analyses conducted using the revised universal soil loss equation 2 rusle2 and usetox models indicated that sheet and rill erosion were on average 28%. Pdf introductionmethodologyresults and discussionconclusion references find, read and cite all the research you need on. Find rill erosion stock images in hd and millions of other royaltyfree stock photos, illustrations and vectors in the shutterstock collection. Detachment in a rill occurs if the sediment in the flow is below the amount the load can transport and if the flow exceeds the soils resistance to detachment. Example of rill erosion and redeposition of sediment at the base of the slope source. Thousands of new, highquality pictures added every day. Rill erosion is a major soil erosion process caused by water on sloping croplands and rangelands in many areas around the world and causes much soil loss cai et al. Sheet and rill erosion soil erosion in europe wiley.
Wind or water erosion is the physical wearing of the earths surface. Certain conditions are necessary for rill initiation and the critical conditions are different with different factors. Sheet, rill and gully erosion is the unwanted removal of soil from the land surface or through incised channels by the action of rainfall and runoff. Rill erosion is the removal of soil by concentrated water running through little streamlets, or headcuts. The erosion process when a raindrop hits the bare soil with enough.
Sheet erosion occurs when these soil particles are. This study was conducted to investigate rill erosion characteristics and their effects on runoff. A rule of thumb is that rill erosion is excessive when average annual rate for. A form of water erosion in which numerous very small and more or less straight channels are produced. Workshop on common criteria for risk area identification. Accurate estimation of the shear stress of flowing water is important in modeling rill and interrill erosion. As detachment continues or flow increases, rills will become wider and deeper. Rill erosion mainly occurs as a result of concentrated overland flow of water. Rill erosion is usually linked with sheet water driven erosion as. Rill erosion is often described as the intermediate stage between sheet erosion and gully erosion. Ephemeral gullies are concentrated flow channels formed when rills. The model followed measured patterns of morphological changes as the rill evolved, which suggests.
Enrichment of organic carbon in sediment transport by. Therefore, an integrated approach to land husbandry must be. Protecting the soil from runoff stops potential land. Rill erosion is one type of water erosion, but it is part of a series of events that begin with raindrops falling on bare soil.
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