13 Types of Soil Erosion Explained
Types of soil erosion are; splash, rill, sheet, gully, tunnel, bank, scalding, soil creep, slumping, floodplain, glacial, chemical, and tillage erosion.
This article discusses the types of soil erosion as follows;
1). Splash Erosion (as one of the Types Of Soil Erosion)
Splash erosion is one of the most basic types of soil erosion.
It involves the separation and redistribution of earth materials as a result of collision with falling raindrops .
The two driving factors behind splash erosion are gravity and pressure. These factors combine to produce the impact which raindrops have on the soil as they fall.
Splash erosion is described as ‘basic’ because it is a simple process compared to other types of soil erosion. Its role is to dislodge earth materials from their original position. Therefore, splash erosion leads mainly to redistribution of soil.
It is not easy to visually detect this type of erosion since it does not involve much movement.
Splash erosion can also be described as a preliminary type of erosion, as it transforms to sheet, gully or rill erosion with the increase in water volume.
Types of Soil Erosion: Splash Erosion (Credit: John, A. Kelley, USDA 2005 .CC BY 2.0.)
2). Rill Erosion
Rill erosion is yet another type of soil erosion that is caused primarily by water.
In rill erosion, the flowing water creates rills in the soil due to mechanical scouring. These rills can be described as numerous, narrow and shallow channels or ridges that form as water carves flow paths through weak portions of the soil .
Rill erosion is most likely to occur in cases where the soil is loose, with little adhesion between particles. It is also likely to occur when stormwater is concentrated within small, defined areas, and flows outward in a radial pattern.
Anthropogenic processes that can contribute to rill erosion are deforestation, leaching and overgrazing.
In agricultural lands, this type of erosion can be prevented or mitigated using practices of sustainable agriculture such as contour farming, conservation tillage and cover cropping .
3). Sheet Erosion (as one of the Types of Soil Erosion)
Sheet erosion is a type of erosion whereby thin layers of soil are uniformly redistributed or removed from their original position .
It can be described as the uniform removal of thin layers of soil by wind or water.
Sheet erosion is often a subsequent development from splash erosion, and affects soil which has already been dislodged and loosened.
Areas that are susceptible to sheet erosion include hilly regions, and regions where a thin layer of loose soil overlies compact soil or rock .
Exposed soil without protective covering is most vulnerable to sheet erosion. Practices like cover cropping reduce the risk of this hazard.
4). Gully Erosion
Gully erosion is one of the most severe types of soil erosion, involving the formation of deep grooves; channels or cavities called gullies, by runoff .
It is an advanced form of rill erosion, which occurs when the volume and/or velocity of runoff increases.
Gullies are generally deeper and wider than rills, with depths that may reach 10m. However, most gullies do not exceed 2m depth .
The geometry or cross section of gullies may vary, ranging from U-shaped to V-shaped outlines, depending on the specific dynamics of erosion involved.
Although gully erosion is mostly related to rainstorms, glaciers can also cause this type of erosion.
The depth and development of gullies depends on various factors, one of which is the type of soil. Weaker soils generally permit the development of deeper gullies than their more-resistant counterparts.
Gully erosion is considered to be a severe type, because it can significantly alter the layout of land, and can render the lad unusable for nearly all purposes including agriculture, industry and construction.
The development and progression of gullies in areas affected by this type of erosion, is a continuous process that may occur through mechanisms like scouring and slumping.
Due to its complexity, gully erosion is associated with other manmade and natural hazards like stormwater pollution and flooding.
Types of Soil Erosion: Gully Erosion (Credit: T. R. Shankar Raman 2008 .CC BY-SA 4.0.)
5). Tunnel Erosion (as one of the Types of Soil Erosion)
Tunnel erosion is a type of erosion involving the active denudation and removal of earth material in the subsurface.
It is also referred to as ‘piping’ and is enhanced by a number of conditions.
Firstly, tunnel erosion is possible where there is an inlet for erosive agents like water. This inlet could be crevices on the surface that permit the entry of runoff into the subsurface.
Secondly, tunnel erosion is enhanced by the presence of weak subsurface soil zones. Such zones include areas where the soil is loose, having low resistance and high vulnerability to scouring and denudation.
In regions dominated by sodic soils (or ‘sodosols’), tunnel erosion is likely to occur due to the relative ease with which the soil is degraded by runoff . Also, all subsurface soils with low water-retention capacity are susceptible to tunnel erosion.
Tunnel erosion can lead to severe land degradation and loss of resources. Extensive loss of subsurface soil can cause the collapse of overlying areas, thereby forming gullies and other collapse structures.
Soil conservation techniques like plastic mulching can reduce the risk of this type of erosion in vulnerable regions.
6). Bank Erosion
Bank erosion is a type of erosion which occurs along the banks of streams and rivers, whereby overflowing water causes the removal or redistribution of soil .
It is one of the types of erosion that can result from both natural and anthropogenic causes.
Bank erosion is relatively common in coastal and riverine areas that are prone to overflow and runoff.
Basically, it occurs when water bodies begin to spill into adjacent areas. This may be facilitated by events like heavy rainfall and flooding.
Aside flooding, any human activity that causes a significant shift in the flow pattern of streams and rivers can lead to bank erosion. Such activities include navigation, and construction of wind energy plants and water dams.
Large offshore wind turbines can alter the flow of water downstream and contribute to bank erosion. Construction, sand mining and other activities that remove vegetation and alter soil structure along the banks can also contribute to the problem.
It is important to note that bank erosion is not the same as water-induced geomorphological changes that occur along stream banks. On the contrary, erosion degrades the geomorphology of banks, and causes the formation of structures like grooves.
Preventing or mitigating this type of erosion requires measures to be taken, to build resistance along river banks, such as re-vegetation and construction of barrier and flow channels for runoff.
7). Scalding Erosion (as one of the types of Soil Erosion)
Scalding erosion is a type of erosion whereby wind or water, forcibly removes the topsoil and exposes subsoil to degradation.
This is another example of the types of soil erosion that are caused by the simultaneous action of multiple factors. In scalding erosion, both wind and water can act simultaneously or alternately to redistribute soil particles.
Usually, it is the topsoil layer that is affected. This layer may be removed, exposing the subsoil underneath.
Provided the subsoil is more resistant, removal may not occur. However, leaching, hardening and other forms of degradation can affect the exposed subsoil.
Scalding is more common in areas where sodosols are dominant, or where soil has a high level of salinity . The subsoil is often composed of adhesive minerals like clay, enabling it to resist removal.
The occurrence of scalding can lead to soil loss and fertility decline.
8). Soil Creep
Soil creep, also known as surface creep; is a type of soil erosion whereby soil is displaced from its position under the influence of gravity .
Aside gravity, other factors that play a role in soil creep include wind and water.
Soil creep is a form of mass movement, and usually occurs at slow rates that are uneasy to detect.
9). Slumping (as one of the Types of Soil Erosion)
Slumping is a type of erosion whereby soil material is displaced by rapid fall in a downslope direction.
Both slumping and soil creep are types of soil erosion that are caused by gravity.
Slumping is most likely to occur in undulating regions. The ‘slump’ usually originates from a zone of weakness along the inclined surface of a slope, where the weight of soil acting downward is greater that the adhesion between the soil mass and the slope.
When slumping occurs, it may leave a depression in the slope, thereby altering its geomorphology.
10). Floodplain Erosion
Floodplain erosion is a type of erosion that occurs in floodplain areas, which extend from stream banks to adjacent segments of the alluvial environs.
This type of erosion is more extensive than bank erosion, engulfing both banks and their surroundings.
The mechanism of floodplain erosion includes topsoil removal and scouring, among others.
Factors that determine the severity of flood plain erosion include water volume and glow velocity.
It is not uncommon for floodplain erosion to cause the degradation of agricultural lands which occur within floodplains .
11). Glacial Erosion (as one of the Types of Soil Erosion)
Glacial erosion is the denudation and redistribution of earth materials by ice, through processes of abrasion, freezing and melting.
As the above definition implies, this type of erosion is dominant in low-temperature ecosystems like tundras.
The three main mechanisms of glacial erosion are freeze-thaw, abrasion and plucking .
Freeze-thaw leads to the breakup and loosening of earth materials, as a result of the repeated expansion-and-contraction effect of glaciers as they freeze and thaw respectively.
Plucking is the removal and displacement of soil particles that have been loosened by freeze-thaw. It usually occurs as frozen glacier transforms to liquid during the thaw process.
Abrasion is the result of frictional contact between glaciers and rocks.
12). Chemical Erosion
Chemical erosion is a type of erosion that is facilitated by interactions between the chemical components of minerals and water.
Another way to state this is that chemical erosion is a type of erosion that is driven solely by chemical reactions.
Dissolution is a common example of a chemical reaction that can lead to erosion. Here, water-soluble minerals like calcite in limestone, dissolve on contact with water. This alters the geomorphology of the landscape involved in dissolution.
Water which has the highest potential to cause chemical erosion is usually slightly acidic. This means that the risk of this type of erosion can increase when stormwater is polluted.
Chemical erosion also depends on the presence of reactive minerals.
13). Tillage Erosion (as one of the Types of Soil Erosion)
Tillage erosion is an anthropogenic form of erosion that is caused by the cultivation of soil during agricultural development.
As implied above, the occurrence of this type of erosion is most likely in agricultural lands. When soil is disturbed by (repetitive) tillage and cultivation, it loses its structural integrity and resilience. This subsequently results in erosion .
Tillage erosion is also facilitated by undulating topography. The risk of occurrence is high in areas of sloping or hilly relief .
Problems like tillage erosion can contribute to food insecurity and world hunger, by reducing the productivity of agricultural lands. Addressing this problem requires the use of soil conservation practices and principles of sustainable agriculture. Contour farming and no till farming are agricultural practices that can reduce the risk of tillage erosion.
Types of soil erosion are;
1. Splash Erosion
2. Rill Erosion
3. Sheet Erosion
4. Gully Erosion
5. Tunnel Erosion
6. Bank Erosion
7. Scalding Erosion
8. Soil Creep
10. Floodplain Erosion
11. Glacial Erosion
13. Tillage Erosion
1). Cama, M.; Schillaci, C.; Kropáček, J.; Hochschild, V.; Bosino, A.; Maerker, M. (2020). “A Probabilistic Assessment of Soil Erosion Susceptibility in a Head Catchment of the Jemma Basin, Ethiopian Highlands.” Geosciences (Switzerland) 10(7):248. Available at: https://doi.org/10.3390/geosciences10070248. (Accessed 27 August 2022).
2). Evelpidou, N. (2012). “Runoff erosion – The mechanisms.” Runoff Erosion. Available at: https://www.researchgate.net/publication/339289610_Runoff_erosion_-_The_mechanisms. (Accessed 28 August 2022).
3). Govers, G.; Giménez, R.; Oost, K. (2007). “Rill erosion: Exploring the relationship between experiments, modelling and field observations.” Earth-Science Reviews 84(3):87-102. Available at: https://doi.org/10.1016/j.earscirev.2007.06.001. (Accessed 28 August 2022).
4). Hagmann, J. (1996). “Mechanical soil conservation with contour ridges: Cure for, or cause of, rill erosion?” Land Degradation and Development 7(2):145-160. Available at: https://doi.org/10.1002/(SICI)1099-145X(199606)7:2<145::AID-LDR224>3.0.CO;2-Z. (Accessed 28 August 2022).
5). Hardie, M. (2009). “Dispersive Soils and Their Management: A technical reference manual.” Available at: https://www.researchgate.net/publication/236147599_Dispersive_Soils_and_Their_Management_A_technical_reference_manual. (Accessed 28 August 2022).
6). Irughe, R. E. (2014). “GEO-ENVIRONMENTAL ASSESSMENT OF GULLY EROSION AT THE UNIVERSITY OF BENIN USING GEOINFORMATION AND ENGINEERING METHODS.” Available at: https://www.researchgate.net/publication/309121351_GEO-ENVIRONMENTAL_ASSESSMENT_OF_GULLY_EROSION_AT_THE_UNIVERSITY_OF_BENIN_USING_GEOINFORMATION_AND_ENGINEERING_METHODS. (Accessed 28 August 2022).
7). Krabbendam, M.; Glasser, N. F. (2011). “Glacial erosion and bedrock properties in NW Scotland: Abrasion and plucking, hardness and joint spacing.” Geomorphology 130(3):374-383. Available at: https://doi.org/10.1016/j.geomorph.2011.04.022. (Accessed 28 August 2022).
8). Lindstrom, M. J.; Lobb, D. A.; Schumacher, T. E. (2001). “Tillage Erosion: An Overview.” Annals of Arid Zone 40(3):345-358. Available at: https://www.researchgate.net/publication/236343069_Tillage_Erosion_An_Overview. (Accessed 28 August 2022).
9). Marzen, M.; Iserloh, T. (2021). “Processes of raindrop splash and effects on soil erosion.” Precipitation (pp.351-371). Available at: https://doi.org/10.1016/B978-0-12-822699-5.00013-6. (Accessed 28 August 2022).
10). Mondal, T.; Tripathy, B. (2020). “River Bank Erosion and Environmental Degradation.” International Journal of Research 07(07):302-313. Available at: https://www.researchgate.net/publication/343797515_River_Bank_Erosion_and_Environmental_Degradation. (Accessed 28 August 2022).
11). Oehm, B.; Hallet, B. (2005). “Rates of soil creep, worldwide: Weak climatic controls and potential feedback.” Available at: https://www.researchgate.net/publication/286913942_Rates_of_soil_creep_worldwide_Weak_climatic_controls_and_potential_feedback. (Accessed 28 August 2022).
12). Wang, Y.; Zhang, Z. H.; Zgang, J.; Jia, L. (2016). “Impact of tillage erosion on water erosion in a hilly landscape.” Science of The Total Environment 551-552(6):522-532. Available at: https://doi.org/10.1016/j.scitotenv.2016.02.045. (Accessed 28 August 2022).
13). Warner, B. P.; Schattman, R.; Hatch, C. E. (2017). “Farming the Floodplain: Ecological and Agricultural Tradeoffs and Opportunities in River and Stream Governance in New England’s Changing Climate.” Available at: https://doi.org/10.1525/cse.2017.sc.512407. (Accessed 28 August 2022).
14). Whiting, P. J.; Bonniwell, E. C.; Matisoff, G. (2001). “Depth and areal extent of sheet and rill erosion based on radionuclides in soils and suspended sediment.” Geology 29(12). Available at: https://doi.org/10.1130/0091-7613(2001)029<1131:DAAEOS>2.0.CO;2. (Accessed 28 August 2022).
15). Wong, V. N. L.; Murphy, B. W.; Koen, T. B.; Greene, R. S.; Dalal, R. C. (2008). “Soil organic carbon stocks in saline and sodic landscapes.” Australian Journal of Soil Research 46(4):378-389. Available at: https://doi.org/10.1071/SR07160. (Accessed 28 August 2022).