Copyright © 2021 Elsevier B.V. or its licensors or contributors. Illustrated by selected examples, this chapter gives an overview of gully-erosion studies employing SFAP at > 30 sites during the last 25 years. Tends to form a dentritic (branching) pattern. Wind erosion is a major cause of GULLY EROSION. Chutes are used at gully heads to safely convey water from the land surface to the gully bed. Table 2. In these methods, the objective is to control gully erosion using vegetation. Large erosion events fill the valley bottoms and smaller events begin to scour them. Rill vs. Gully Erosion: Erosion is a fact of nature and part of a process that creates sediments. The great potential of SFAP for modeling and measuring such complex erosion forms, coupled with recent developments in UAS technology and SfM-MVS photogrammetry, is securing SFAP a key role in gully-erosion research in the future. Sealing the coal pile is useful in heavy rain areas but is not practical for working piles. The important input factors for gully erosion susceptibility assessment were obtained from different sources such as literature reviews and field surveys. Erosion caused by concentrated flow begins where overland flow converges to channelized flow conditions. Also, the results indicate that in LDA and QDA models, 13.44% and 22.61% of total area is located in the very high susceptibility class to soil erosion, respectively. In these models, gully erosion is represented as a channel-erosion process in which erosion occurs where transport capacity of flow is greater than sediment load in the channel (Poesen et al., 2003). Prevention is by pair or single planting of willows up the valley bottom at 15–20 m spacing and at weak points developing a planted block with 2–3 rows of willows planted at 1.5 m spacing across the valley bottom and in an area fenced out from grazing. 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. Constructing the pile with an appropriate profile and top facilitates runoff (with convex longitudinal profile and no flat-topped center, or slightly concave cross-sectional profile, or slightly crowned top for compacted piles). Gully erosion is a global driver of soil and landscape degradation. When rills increase in size, they become gullies. Definition of gully (Entry 3 of 3) transitive verb. : to make gullies in. Draining the stockpile toe is beneficial for preventing minor instabilities that could lead to an overall failure. Gullies are permanent erosional forms that develop in many parts of the world, particularly in arid and semi-arid environments. Note the willow root mat grown over the dam structure. They work best on deep soils, such as loess soils. Gully erosion results when small erosion problems are not corrected in time. Each type is associated with the progressive concentration of runoff water as it moves downstream. These form under conditions of high relief on easily eroded bedrock in climates favorable to erosion. To wear a deep ditch or channel in. However, independent model testing showed that EGEM failed to predict gully cross-section areas for the studied cropland environments (Poesen et al., 2003). It can be more effectively estimated using process-based soil erosion models. अवनालिका अपक्षरण की परिभाषा | Definition of Gully Erosion in Hindi !! By specifically considering the gully headcut effect, Casali et al. Usually gullies from field runoff form in the same place year after year, especially in tilled fields. Figure 7. Moisture recycling. A deep ditch or channel cut in the earth by running water after a prolonged downpour. Figure 6. Once bare peat is exposed, vertical incision of gullies occurs by normal fluvial erosion processes. G.R. The high sediment loads carried by Asian rivers are partly a consequence of land-use practices, particularly land-clearing practices for agriculture that lead to erosion, a situation likely to continue as a consequence of the expansion of agriculture in Africa, Asia, and Latin America (Hall, 2002). As the volume of concentrated water increases and attains more velocity on slopes, it enlarges the rills into gullies. intransitive verb. Once the base of the gully is eroded to the mineral substrate at the base of the peat, the rate of vertical incision is reduced and the gully cross sections become characteristically rectangular in more mature gullies. Results of validation showed that LDA and QDA models with area under the curve values of 0.875 and 0.8620 are good predictors for gully erosion susceptibility mapping. In this environment, as an erosion prevention measure all drainage lines in pastured hill country are pair planted with tree willows at 15–20 m spacing and measures taken to insure the grassed surface is not broken, so allowing a gully head to form. Any concentration of surface runoff is a potential source of gully erosion. The same forces at work in streambank erosion are seen in soils on… Pielke et al. Gully erosion, however, can also occur within a watercourse, typically within the upper reaches, and typically resulting from an active ‘head-cut’ migrating rapidly up the valley. Various conditions make such erosion possible: the natural vegetation securing the soil may have been destroyed by human action, by fire, or by a climatic change; or an exceptional storm … Consumptive water use has declined there, the water table has risen, and salt has moved into the surface soils so that large tracts of land have become less suitable or unusable for agriculture (Anderies et al., 2001; Briggs and Taws, 2003). Gully erosion occurs when runoff water accumulates and rapidly flows in narrow channels during or immediately after heavy rains or melting snow, removing soil to a considerable depth. Gully erosion is defined as the removal of the top soil along drainage channels by surface water runoff; it is the type of soil erosion that consists of an open, incised and unstable channel generally more than 30cm deep. : to undergo erosion : form gullies. Rill erosion is often described as the intermediate stage between sheet erosion and gully erosion. The GESMs (CART, GLM, and CART–GLM) represents the low to very high susceptibility of a gully erosion occurrence. This erosion can be calculated for individual storms and can be summed for a yearly estimate. Example sentences with "gully erosion", translation memory. There are also indications that increased vapor flows through irrigation can alter local and regional climates (Pielke et al., 1997; Chase et al., 1999). Reclaiming the coal from the toe of the pile by front-end loaders should be avoided because of the hazard; as coal dries out and adhesion between particles becomes weaker, the unstable sides of the pile may collapse. Gully erosion susceptibility map produced by the CART model. Gully erosion is the erosion process whereby water concentrates in narrow channels and over short periods removes the soil. Gully Erosion. In this way, areas with certain soil types, less vegetation cover, and moderate to steep slopes identified as prone to the development of gullies are selected by the root nodes of the models. Change quantification based on the detailed maps and DEMs provides additional information on the differences in headcut retreat behavior which cannot be described by simple linear measures, and the spatially continuous survey of the entire form offers the possibility of distinguishing different zones and processes of activity both at the gully rim and within the gully interior. translation and definition "gully erosion", Dictionary English-English online. Finally, the validation dataset, which was not used in the modeling process, was considered to validate GESMs using the receiver operating characteristics curve. Gully erosion is a well-defined water worn channel (Monkhouse and Small, 2008). Gully erosion: The running water cuts through the clayey soil and makes deep channels in it. Gully erosion is an advance stage of rill erosion as rill erosion is the advanced stage of sheet erosion. During the rainy season, when the soil becomes saturated, and the gully banks are undermined and scoured by channel erosion, big soil blocks start sliding down the banks and are washed away through the gully channel. Ephemeral and classic gully are forms of erosion created by the concentrated flow of water. MARS is a nonparametric statistical technique that can be used to construct a model capable of predicting the location of gullies (Gomez Gutierrez et al., 2009). James S. Aber, ... Susan E.W. We use cookies to help provide and enhance our service and tailor content and ads. Erosion caused by channelized flow conditions may contribute The main purpose of this study was to produce gully erosion susceptibility maps (GESMs) using R-based data-mining linear discriminant analysis (LDA) and quadratic discriminant analysis (QDA) models and to compare their performances in Shahroud Watershed, Semnan Province, Iran. The effect on the soil is similar to that from sheet erosion. the process by which the surface of the earth is worn away by the action of water, glaciers, winds, waves, etc. It is a recently extended drainage channel that transmits ephemeral flow, steep side, steeply sloping or vertical head scarf with a width greater than 0.3 m and a depth greater than 0.6 m (Brice, 2006). Gully erosion constitutes the most severe form of soil erosion in arid and semiarid landscapes. I. McIvor, ... Z. Pu, in Encyclopedia of Agriculture and Food Systems, 2014. Farming with terraces may be inconvenient, and they may limit the choice of farming practices. It is the process by which soil is removed by surface water runoff along the drainage lines, forming deep channels. Salt-affected soils in irrigation schemes are often related to poor soil and water management, in addition to the unsuitability of many soils for irrigation. Ekmann, P.H. Erosion caused by concentrated flow begins where overland flow converges to channelized flow conditions. Gully erosion is defined as the erosion process whereby runoff water accumulates and often recurs in narrow channels and, over short periods, removes the soil from this narrow area to considerable depths.Permanent gullies (e.g. Rill erosion is a type of erosion that results in small, yet well defined streams. Gully erosion may occur as a result activity of man on the land surface such as tin mining, construction, grazing, deforestation and farming activities. Compacting the entire coal pile, or selected areas of it, can reduce the tendency for the saturated coal to suddenly lose strength and to flow. Cross-sectional form of gullies is typically V-shaped in the initial stages of incision. Ephemeral Cropland Gullies: In general, an ephemeral cropland gully is larger than a rill and smaller than a gully. Gully erosion produces channels larger than rills. Gully erosion is a global driver of soil and landscape degradation. Gully erosion results when the top soil is … Repairing gully erosion | Agriculture and Food. It consists of open, unstable channels that have been cut more than 30 centimetres deep into the ground. Gully erosion is a widespread and often dramatic form of soil erosion caused by flowing surface water. अवनालिका अपक्षरण की परिभाषा | Definition of Gully Erosion in Hindi !! Instability in coal piles results from two types of slope failure: shallow slipping and deep-seated sliding, which is the type that causes flowslides. Once started, gullies will continue to move by headward erosion or by slumping of the side walls. Minimizing stockpile height during the rainy season; in case of busy shipping schedules and heavy rain, access roads should be closed to personnel; if a coal slide occurs, it should be cleaned up and restacked. Gully erosion (Figure 6) occurs where concentrated surface water scour out the regolith and underlying rock with the debris being either deposited downslope or transported into river systems creating major downstream problems. Gully erosion damage includes losses resulting from land voiding and any ephemeral gully damage, sheet and rill erosion damage, or impaired land use that is interrelated with gully erosion. Building drainage slopes can facilitate surface runoff. (3) In the “Without project” column, enter the average annual damage that will continue to be incurred without project installation. It has been suggested that large-scale deforestation can reduce moisture recycling, affect precipitation (Savenije, 1995, 1996; Trenberth, 1999), and alter regional climates, with indications of global impacts (Kabat et al., 2004; Nemani et al., 1996; Marland et al., 2003; Savenije, 1995). Sheet erosion: Water flows in a large quantity in the form of sheets and erodes the soil. Now, let’s learn about what gully erosion is and what are its various features. While many Australian and Southern African waters are naturally silty, many have experienced increased silt loads as a result of agricultural practices (Davies and Day, 1998). Gully, trench cut into land by the erosion of an accelerated stream of water. J.M. Erosion definition, the act or state of eroding; state of being eroded. As the name suggests gully, the erosion is in the shape of deep channels on the surface of the earth and it is basically an advanced form of rill erosion. lies 1. This gully formed overnight in 1900-year-old uncemented ignimbrite west of Taupo, New Zealand. Gully erosion susceptibility map produced by the CART and GLM ensemble models. Wikipedia Dictionaries. Terrace edges need to be protected and either grassed waterways developed or flumes constructed. Gully erosion Gullies are … Soil Erosion and Degradation: Simple Definition, Causes ... Fire Science | Research topics | PSW. 30-4 illustrates that the maximum areas of this lower part of the study area fall under very low to moderate susceptibility of gully erosion and the uppermost part of this basin falls under the high potential zone of gully development. Aber, in Small-Format Aerial Photography and UAS Imagery (Second Edition), 2019. Regional studies in West Africa (Savenije, 1996; Zheng and Eltathir, 1998), the United States (Baron et al., 1998; Pielke et al., 1998), and East Asia (Fu, 2003) have illustrated the ways in which changes in land cover affect green water flows, with impacts on local and regional climates. i. Field Runoff Gullies. Gully erosion. the gradual decline or disintegration of … Natural Vegetation: If the runoff that is causing the gully is diverted and grazing is controlled from the eroded area, natural vegetation begins to get established. ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. Spatial Modeling in GIS and R for Earth and Environmental Sciences, Spatial Modeling of Gully Erosion Using Linear and Quadratic Discriminant Analyses in GIS and R, Small-Format Aerial Photography and UAS Imagery (Second Edition), Agroforestry: Conservation Trees and Erosion Prevention, Encyclopedia of Agriculture and Food Systems, Rowntree, 1991; Oygarden, 2003; Cheng et al., 2007; Capra et al., 2009, The most areally extensive form of peatland erosion is, Bower, 1961; Coupar et al., 1997; Cooper and Loftus, 1998; McHugh et al., 2002; Evans and Warburton, 2007, In many parts of the world, extensive sheet wash and, Terrace systems are highly effective at preventing excessive rill erosion, eliminating ephemeral, Reference Module in Earth Systems and Environmental Sciences. In these methods, the objective is to control gully erosion using vegetation. To control flowslides, experience has shown that: Controlling the moisture content of the pile can decrease the risk of flowsliding. Significant conditions that could lead to flowslides include the following: Saturation of the stockpile base due to the infiltration of heavy rainfall, leading to the potential of a deep-seated slip; Redistribution of moisture within the coal at placement (there is a threshold moisture content below which no saturated zone develops); Loosely stacked coal (prone to structural instability); Particle size distribution (migration of fine coal particles under the influence of water flow causes local water saturation and reduction in shear strength). Hill slopes are prone to sheet erosion and rill erosion. The gully form and severity is very dependent on the rock type. Gully Erosion: Erosion is a process that moves soil and minerals from one location to another typically either my water or wind. DEFINITION Gully treatment is the stabilization of active gullies by vegetative or structural measures or a combination thereof. This can cause water logging and salinization, which are extensively described for irrigated agriculture (Postel, 1998). 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. It happens when water from rainfall does not soak into the soil, but runs across it instead. Enclosing the pile keeps the coal dry but is an expensive option and not applicable at coal blending terminals. The contribution of gully erosion to the total soil loss from water erosion ranges from 10% to 94% worldwide (Poesen et al., 2003). In gully control, temporary structural measures such as woven-wire, brushwood, logs, loose stone and boulder check dams are used to facilitate the growth of permanent vegetative cover. The stockpile shows a flat final slope and a temporary steep scarp that subsequently slumps back to the angle of repose. GLM, General linear model. ephemeral gully, classic gully and stream bank. Some studies have found that ephemeral gully erosion contributes about 40% of the watershed sediment yield. 30-6). Terrace systems are highly effective at preventing excessive rill erosion, eliminating ephemeral gully erosion, reducing sediment yield, conserving soil moisture, protecting landscape quality, and increasing land value. Terraces require a significant investment to build and maintain. CART, Classification and regression tree. Gully erosion is a result of the interaction of land use, climate and slope. In the first case, wetting of the surface layer can lead to erosion gullies and to shallow slipping with small flows depositing saturated coal at the toe of the slope. Amiya Gayen, Hamid Reza Pourghasemi, in Spatial Modeling in GIS and R for Earth and Environmental Sciences, 2019. This chapter discusses gully erosion monitoring. gully erosion is believed to be as significant as sheet and rill erosion in terms of sediment delivered from cropland acres to streams, rivers, and lakes. (2003) developed an event-based model to estimate ephemeral gully erosion. However, gully is visually the most impressive of all types of erosion (El-Swaify, 2000). ... partial blocking of the waterway often causes overfalls and increased gully erosion, and more land and soil may be lost than if the gully were untreated. Examples of Erosion. Gully erosion susceptibility assessment by means of GIS-based logistic regression: A case of Sicily (Italy). Figure 30-5. Tree-covered landscapes provide an important regulating service by consuming rainfall through high evapotranspiration, limiting groundwater recharge, and keeping the groundwater low enough to prevent salt from being carried upward through the soil. Gullies are not obliterated by tillage. However, the CART and ensemble of both models represent more appropriate results for gully erosion susceptibility assessment (Fig. Sheet and rill erosion. Gully erosion is one of the most devastating forms of soil erosion and can be expressed in terms of onsite effects such as destruction of property and natural habitats, reduction of land productivity, and offsite effects such as sedimentation of reservoirs and rivers which call for rapid solutions (Ayele et al., 2015; Additionally, the Ephemeral Gully Erosion Model (EGEM) was specially developed for estimating the volume from gully erosion (Merkel et al., 1988). This method estimates past erosion and cannot predict future erosion. Extreme gully erosion can progress to formation of badlands. noun the act or state of eroding; state of being eroded. Sample 1 Sample 2 30-5). Gully erosion is one of the most important types of water erosion that causes the destruction of agricultural and range lands in arid and semiarid areas. Search gully erosion and thousands of other words in English definition and synonym dictionary from Reverso. This slope failure results in economic loss associated with cleanup costs, loss of production, damage to equipment, and danger to personnel. Rates of lateral gully wall recession have been widely measured using erosion pins. Gully erosion Gullies are … The results achieved with small-format aerial photography for monitoring gully erosion continue to demonstrate that SFAP can be considered an advantageous alternative to field methods or conventional aerial photography. Reported rates of erosion of bare peat surfaces measured by erosion pins, D. Molden, ... D. Peden, in Treatise on Water Science, 2011. Water builds up in a soil profile when the rate of input exceeds the rate of throughput (e.g., when irrigation volumes are greater than crop water consumption by way of evapotranspiration). P. Gao, in Treatise on Geomorphology, 2013. According to the gully erosion susceptibility map, which is produced based on the GLM technique, the maximum area of the basin with respect to the total area is found to have low susceptibility to gully erosion. It is the most spectacular form of erosion. Gully erosion happens when runoff concentrates and flows strongly enough to detach and move soil particles. It consists of open, unstable channels that have been cut more than 30 centimetres deep into the ground. Failures can happen with relatively fresh coal (placed within the previous 2 weeks), and a significant coal pile height increases the risk of collapse. While it is not always easy to differentiate natural erosion from human-induced erosion. 30-4–30-6). In agricultural watersheds, gully erosion can account for as high as 80% of the total soil erosion (Capra and Scicolone, 2002). Generally, the physically based models described previously for estimating rill erosion can also evaluate gully erosion on hillslopes. Gully erosion Definition from Encyclopedia Dictionaries & Glossaries. Gully erosion is a highly visible form of soil erosion which can indicate an imbalance in regular watercourse flow. Gullies resemble large ditches or small valleys, but are metres to tens of metres in depth and width. Gully erosion is one of the most devastating forms of soil erosion and can be expressed in terms of onsite effects such as destruction of property and natural habitats, reduction of land productivity, and offsite effects such as sedimentation of reservoirs and rivers which call for rapid solutions (Ayele et al., 2015; From: Spatial Modeling in GIS and R for Earth and Environmental Sciences, 2019, Alireza Arabameri, Hamid Reza Pourghasemi, in Spatial Modeling in GIS and R for Earth and Environmental Sciences, 2019. Tillage destroys soil structure and reduces the residue cover, leaving the soil surface more prone to erosion and runoff. Prevention is much more effective than repair as once the erosion is into the bedrock it is very difficult to get trees (or any other plant material) established. Rill erosion is considered in the RUSLE calculations. Gully erosion washes away the fertile soil, making the soil unproductive. Human land use, and especially changes in land use, may accelerate gully expansion by head cutting, sidewall collapse, piping, floor erosion, and other processes, which lead to widespread land degradation and potential damage to human structures and activities. The whole catchment needs to be retired from grazing and planted in closed canopy trees with the eroding surfaces repeatedly planted with willow wands to create a vegetated surface. Meaning of gully. Channel erosion along gully beds is the main cause of land slides on gully banks. First, 172 gully erosion locations were obtained using Google Earth images and extensive field surveys. Gully erosion is widespread across the upland peatlands of the UK and Ireland (Bower, 1961; Coupar et al., 1997; Cooper and Loftus, 1998; McHugh et al., 2002; Evans and Warburton, 2007). Ephemeral and Classic Gully ErosionWorksheet Forms of erosion by water include sheet and rill, ephemeral gully, classic gully and stream bank. The most areally extensive form of peatland erosion is gully erosion. Hillsides are more prone to gully erosion when they are cleared of vegetation, through deforestation, over-grazing or other means. Gully Erosion. Bare peat typically shows recession rates of up to 40 mm yr–1. The overall trend, however, in irrigation is one of increased pumping and reduced water levels, but good salt management increases a critical issue in particular in arid regions. Clearing woody vegetation for pastures and crops can also lead to dryland salinization. The higher index represents a more susceptible area to gully erosion. v.tr. Freshly exposed fibrous peat is relatively resistant to erosion by surface flow (Carling et al., 1997), but frost action and desiccation of the bare peat surface produce a friable weathered layer which is easily mobilized by surface flow across gully walls and by raindrop impacts (Francis, 1990; Labadz et al., 1991; Klove, 1998; Evans and Warburton, 2007). The mapping and monitoring of the impact of gully erosion; Giga-fren. Many of these factors may be interpreted or analyzed and mapped with SFAP. (a) A discontinuous gully and (b) gully control achieved by stabilizing the base level through construction of debris dams supported by willows. Gullies function as sediment sources, stores, and conveyors that link hillslopes to downstream channels. 2.4 Gully treatment by grade stabilization structures. It is a recently extended drainage channel that transmits ephemeral flow, steep side, steeply sloping or vertical head scarf with a width greater than 0.3 m and a depth greater than 0.6 m (Brice, 2006). This type of erosion is calculated by RUSLE2, the water erosion prediction equation. Enrich your vocabulary with the English Definition dictionary Tillage destroys soil structure and reduces the residue cover, leaving the soil surface more prone to erosion and runoff. An extreme form of soil erosion, in its best incarnation a gully is a difficult-to-discern and entirely unproductive seam in a field, one cut by the fierce … They are easily identified through visual observation. Gully erosion is the extreme stage of soil erosion. A gully is usually dry except after periods of heavy rainfall or after the melting of snow or ice. Foster, in Encyclopedia of Soils in the Environment, 2005. See more. A common limitation of these models is that they lack routines to predict the location of gullies (Poesen et al., 1998). While the tillage does fill in the gully, each time the gully washes out again, the soil is lost from the gully and from along the sides of the gully as that soil was used to repair the gully. Gully erosion is best characterised as a ‘bed instability’ that subsequently causes in ‘bank instabilities’. Hillsides are more prone to gullying when they are cleared of vegetation, through deforestation, over-grazing or other means. Gully erosion is a well-defined water worn channel (Monkhouse and Small, 2008). In the southern Pennines of the UK, which are probably the most eroded blanket peatlands in a global context, Evans and Lindsay (2010) mapped 34% of the land surface as gullied, effectively a loss of 34% of peatland volume over approximately the last millennium (Tallis, 1985). Rill erosion is often described as the intermediate stage between sheet erosion and gully erosion. For example, a waterfall may form, with runoff picking up energy as it plunges over the gully head. Table 2 reports the range of recession rates recorded across the UK and more widely. Gully erosion is the process by which gullies are formed. en The Comanche and Spanish forces met in a series of running battles between August 31 and September 3, 1779; Tabivo Naritgant was killed in combat, along with his first-born son and fifteen others, on September 3 somewhere between the present day cities of Pueblo, Colorado and Colorado City, Colorado, probably in a gully of the St. Charles River. Gully Erosion means a small valley or ravine originally worn away by running water and serving as a drainage way after prolonged heavy rains. Chute structures are useful for gully head control and they could be used for drops up to 5 to 6 m. Chute structures require less construction material than drop structures of the same capacity and drop. Each type is associated with the progressive concentration of runoff water as it moves downstream. Moderate and high zones make up the upper and middle parts of the study area (Fig. Tillage in an area affected by ephemeral gullying removes thin layers of topsoil from ungullied areas to fill the gully. This limitation is overcome by a recently developed data-mining technique, Multivariate Adaptive Regression Splines (MARS). In the cases of our study, the variables in the upper part of the tree indicate spatially undefined areas, with a risk of gully formation, and the variables in the lower part of the tree enable location of the gully at a specific position. gully erosion. The GLM model represents 0.0–0.92 susceptibility values, representing low and high susceptibility for development of gullies. The very severe to extreme gully erosion is restricted to argillites (crushed), mudstone, and fine siltstones with each rock type having its characteristic gully shape. Photos G. Eyles. The total amount of annual gully erosion has for years been calculated by measuring gully width, depth, and length using a steel tape and global positioning system (GPS) (Rowntree, 1991; Oygarden, 2003; Cheng et al., 2007; Capra et al., 2009).