Physical processes
- Rainfall and surface runoff. Rainfall, and the surface runoff which may result from rainfall, produces four main types of soil erosion: splash erosion, sheet erosion, rill erosion, and gully erosion.
- Rivers and streams. ...
- Coastal erosion. ...
- Glaciers. ...
- Floods. ...
- Mass wasting. ...
Where are places where erosion most likely to happen?
The vulnerability of soils to water erosion depends on:
- rainfall intensity (erosivity)—high intensity rainfall creates serious risk as heavy drops on bare soil causes the soil surface to seal
- nature of the soil (erodibility)—clay soils vary in their ability to withstand raindrop impact
- slope length—if a slope is long, water running down the slope becomes deeper and moves faster, taking more soil with it
Where would erosion have the greatest effect?
What are the 5 forces that cause erosion?
- Temperature. rock expands with hot temperature and contracts with cold ones. …
- Ice. when water freezes in the cracks of the rocks it expands, causing small pieces to break off. …
- Wind. wind action carries away small rock particles of the rock surface. …
- Vegetation. …
- Running Water.
Where does erosion cause the most problems?
Erosion leads to huge deposition of sediments into drains. This may cause drainage problems. Water sources such as rivers, streams, and lakes can be polluted through extensive inputs of pesticides, nitrogen and phosphorous. READ: Thunderstorm: Formation, Types and Effects. Deposition of sediments in rivers can damage river ecosystems.
What are the 4 main causes of erosion?
What are the 4 main causes of erosion?
- Water. Water is the most common cause of soil erosion. …
- Wind. Wind can also make soil erode by displacing it. …
- Ice. We don’t get much ice here in Lawrenceville, GA, but for those that do, the concept is the same as water. …
- Gravity. …
- Benefits of a Retaining Wall.
Where is erosion located?
Erosion happens at the tops of mountains and under the soil. Water and chemicals get into the rocks and break them up through those mechanical and chemical forces. Erosion in one area can actually build up lower areas. Think about a mountain range and a river.
What are 4 examples of erosion?
Some erosion examples include wind erosion, water erosion, glacial erosion, temperature erosion, and mass wasting (such as landslides).
What is a good example of erosion?
“I have an example of erosion in my own backyard! When it rains in my backyard, the rain carries the soil to the edge of my backyard near the fence and creates a huge mud puddle. This is the process of moving soil to a new location, which is called erosion.”
Are rivers examples of erosion?
Rivers - Rivers can create a significant amount of erosion over time. They break up particles along the river bottom and carry them downstream. One example of river erosion is the Grand Canyon which was formed by the Colorado River.
Does erosion happen under the ocean?
Erosion by Water Liquid water is the major agent of erosion on Earth. Rain, rivers, floods, lakes, and the ocean carry away bits of soil and sand and slowly wash away the sediment.
Where does the most erosion occur in a river?
Most river erosion happens nearer to the mouth of a river. On a river bend, the longest least sharp side has slower moving water. Here deposits build up. On the narrowest sharpest side of the bend, there is faster moving water so this side tends to erode away mostly.
What landforms are made by erosion?
Landforms created by erosion include headlands and bays, caves, arches, stacks and stumps. Longshore drift is a method of coastal transport.
Where does erosion occur in Canada?
In Canada excellent examples occur in the Nahanni region, YT, and in many parts of the Rocky Mountains. Physical water erosion occurs when moving water achieves sufficient velocity to pick up or move loose particles or to pry fragments loose from SOIL or bedrock.
Where do erosion and deposition occur in a river?
In rivers, deposition occurs along the inside bank of the river bend [This "area" is where water flows slower], while erosion occurs along the outside bank of the bend, where the water flows a lot faster.
What is erosion in geography rivers?
Erosion is the process that wears away the river bed and banks. Erosion also breaks up the rocks that are carried by the river. There are four types of erosion: Hydraulic action - This is the sheer power of the water as it smashes against the river banks.
Can snow cause erosion?
Water – Water is the leading cause of erosion. When a temporary thaw or warmer weather returns, snow and ice turn to water that can cause soil loss due to melt runoff. Unprotected soil can break down, compromising landscapes, lawns and gardens susceptible to further damage.
What are the four types of erosion?
Rain, rivers, floods, lakes, and the ocean carry away bits of soil and sand and slowly wash away the sediment. Rainfall produces four types of soil erosion: splash erosion, sheet erosion, rill erosion, and gully erosion.
Which type of landscape is most eroded?
Deserts, which generally lack thick vegetation, are often the most eroded landscapes on the planet. Finally, tectonic activity shapes the landscape itself, and thus influences the way erosion impacts an area. Tectonic uplift, for example, causes one part of the landscape to rise higher than others.
How does topography affect erosion?
Topography, the shape of surface features of an area, can contribute to how erosion impacts that area. The earthen floodplains of river valleys are much more prone to erosion than rocky flood channels, which may take centuries to erode. Soft rock like chalk will erode more quickly than hard rocks like granite.
How does ocean erosion affect landscape?
The action of erosion can create an array of coastal landscape features. For example, erosion can bore holes that form cave s. When water breaks through the back of the cave, it can create an arch. The continual pounding of waves can cause the top of the arch to fall, leaving nothing but rock columns called sea stack s. The seven remaining sea stacks of Twelve Apostles Marine National Park, in Victoria, Australia, are among the most dramatic and well-known of these features of coastal erosion.
What is the term for the process in which earthen materials are worn away and transported by natural forces such as wind or?
Encyclopedic Entry. Vocabulary. Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water. A similar process, weathering, breaks down or dissolve s rock, but does not involve movement.
How does plant growth contribute to physical erosion?
Plant growth can also contribute to physical erosion in a process called bioerosion. Plants break up earthen materials as they take root, and can create cracks and crevice s in rocks they encounter. Ice and liquid water can also contribute to physical erosion as their movement forces rocks to crash together or crack apart. ...
How deep is the Fish River Canyon?
Over millions of years, the Fish River wore away at the hard gneiss bedrock, carving a canyon about 160 kilometers (99 miles) in length, 27 kilometers (17 miles) wide, and 550 meters (1,084 feet) deep.
Where does erosion occur in a river?
Most river erosion happens nearer to the mouth of a river . On a river bend, the longest least sharp side has slower moving water. Here deposits build up. On the narrowest sharpest side of the bend, there is faster moving water so this side tends to erode away mostly.
What are the human activities that can cause erosion?
Intensive agriculture, deforestation, roads, anthropogenic climate change and urban sprawl are amongst the most significant human activities in regard to their effect on stimulating erosion. However, there are many prevention and remediation practices that can curtail or limit erosion of vulnerable soils.
How does gully erosion occur?
Gully erosion occurs when runoff water accumulates and rapidly flows in narrow channels during or immediately after heavy rains or melting snow, remo ving soil to a considerable depth. A gully is distinguished from a rill based on a critical cross-sectional area of at least one square foot, i.e. the size of a channel that can no longer be erased via normal tillage operations.
What are the causes of land degradation?
Water and wind erosion are the two primary causes of land degradation; combined, they are responsible for about 84% of the global extent of degraded land, making excessive erosion one of the most significant environmental problems worldwide.
What are the agents of erosion?
Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and waves; glacial plucking, abrasion, and scour; areal flooding; wind abrasion; groundwater processes; and mass movement processes in steep landscapes like landslides and debris flows.
How much has erosion increased?
While erosion is a natural process, human activities have increased by 10-40 times the rate at which erosion is occurring globally. At agriculture sites in the Appalachian Mountains, intensive farming practices have caused erosion at up to 100 times the natural rate of erosion in the region.
What is the process of removing soil and rock?
Natural processes that remove soil and rock. For other uses, see Erosion (disambiguation). An actively eroding rill on an intensively-farmed field in eastern Germany. 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 Earth's crust, ...
How does erosion occur in rivers?
In rivers and estuaries, the erosion of banks is caused by the scouring action of the moving water, particularly in times of flood and, in the case of estuaries, also by the tidal flow on the ebb tide when river and tidewater combine in their erosive action. This scouring action of the moving water entrains (that is, draws in and transports) sediments within the river or stream load. These entrained sediments become instruments of erosion as they abrade one another in suspended transport or as they abrade other rock and soil as they are dragged along the river bottom, progressively entraining additional sediments as long as the river’s volume and velocity of the stream continues to increase. As the velocity of the river decreases, the suspended sediments will be deposited, creating landforms such as broad alluvial fans, floodplains, sandbars, and river deltas. The land surface unaffected by rivers and streams is subjected to a continuous process of erosion by the action of rain, snowmelt, and frost, the resulting detritus (organic debris) and sediment being carried into the rivers and thence to the ocean.
What is erosion in science?
The broadest application of the term erosion embraces the general wearing down and molding of all landforms on Earth’s surface, including the weathering of rock in its original position, the transport of weathered material, and erosion caused by wind action and fluvial, marine, and glacial processes. This broad definition is more correctly called ...
What is the definition of erosion?
A narrow and somewhat limiting definition of erosion excludes the transport of eroded material by natural agencies, but the exclusion of the transport phenomenon makes the distinction between erosion and weathering very vague. Erosion, therefore, includes the transportation of eroded or weathered material from the point of degradation ...
How do sediments become instruments of erosion?
These entrained sediments become instruments of erosion as they abrade one another in suspended transport or as they abrade other rock and soil as they are dragged along the river bottom, progressively entraining additional sediments as long as the river’s volume and velocity of the stream continues to increase .
How to tell erosion from weathering?
With both processes often operating simultaneously, the best way to distinguish erosion from weathering is by observing the transportation of material.
How does glacier erosion occur?
Glacial erosion occurs in two principal ways: through the abrasion of surface materials as the ice grinds over the ground (much of the abrasive action being attributable to the debris embedded in the ice along its base); and by the quarrying or plucking of rock from the glacier bed. The eroded material is transported until it is deposited or until the glacier melts.
What is the term for the removal of surface material from Earth's crust?
erosion, removal of surface material from Earth’s crust, primarily soil and rock debris, and the transportation of the eroded materials by natural agencies (such as water or wind) from the point of removal.
What happens to the rock during physical erosion?
In physical erosion, the rock breaks down but its chemical composition remains the same , such as during a landslide or bioerosion, when plants take root and crack rocks. Explore the process of erosion with this collection of resources.
What is the term for the process in which earthen materials are worn away and transported by natural forces such as wind or?
Geology, Geography, Earth Science, Physical Geography. Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water. Grades. 6 - 12+.
What is the process of breaking down rocks?
Erosion is the process where rocks are broken down by natural forces such as wind or water. There are two main types of erosion: chemical and physical. Chemical erosion occurs when a rock’s chemical composition changes, such as when iron rusts or when limestone dissolves due to carbonation. In physical erosion, the rock breaks down ...
What are the four major types of landforms?
A landform is a feature on the Earth's surface that is part of the terrain. Mountains, hills, plateaus, and plains are the four major types of landforms. Grades.
What is the USGS?
Physical Geography, Geography, Mathematics, Earth Science, Biology. The United States Geological Survey, also called USGS, is one of the many departments in the U.S. government. USGS scientists study the entire landscape of the country. Grades.
What is sediment in encyclopaedia?
Encyclopedic entry. Sediment is solid material that is moved and deposited in a new location. Sediment can consist of rocks and minerals, as well as the remains of plants and animals.
What Is Erosion?
Erosion is a geological process in which earthen materials (i.e., soil, rocks, sediments) are worn away and transported over time by natural forces such as water or wind; sometimes this is sped up by poor management or other human impacts on land. The natural process of river erosion, in fact, created the Grand Canyon, as the Colorado River cut deep and wide through the rock over millions of years, and glacial erosion carved Yosemite National Park’s iconic landscape. (The difference between weathering and erosion is that in the process of weathering, materials are worn away but not transported. And erosion is the opposite of deposition, when natural forces leave earthen materials behind.)
What are the causes of erosion?
Climate is also a major driver of erosion. Changes in rainfall and water levels can shift soil, extreme fluctuations in temperature can make topsoil more vulnerable to erosion, and prolonged droughts can prevent plants from growing, leaving soil further exposed.
Why is soil erosion increasing?
Larger wildfires: A recent study by the U.S. Geological Survey found that soil erosion is expected to increase as more wildfires destroy landscapes; areas with less vegetation and groundcover are more prone to erosion by wind and water. In 2017, California experienced one of its worst wildfire seasons followed by heavy rains across parts of the state. The combination resulted in deadly mudslides.
What factors affect the rate of soil erosion?
The rate of soil erosion depends on many factors, including the soil’s makeup, vegetation, and the intensity of wind and rain. Because our own activities can also influence the speed of soil erosion, we have the power (and the responsibility) to solve one of the planet’s greatest environmental challenges.
What is the most underappreciated natural resource?
But what about the dirt? It seems soil is one of the planet’s most underappreciated natural resources. Yet healthy soil is the foundation for agriculture; it also plays a vital role in protecting the air we breathe, the water we drink, the food we eat—and even our climate.
When was soil erosion declared a national threat?
In April 1935 , Congress declared soil erosion “a national menace” and established the Soil Conservation Service—known today as the Natural Resources Conservation Service (NRCS)—within the U.S. Department of Agriculture to instruct farmers on how to prevent erosion.
Why is there no vegetation in the land?
Since there’s no vegetation to absorb the water, hold dirt in place, or break up the energy of falling raindrops, a rainstorm leads to increased runoff and erosion.
Where does the word erosion come from?
The word erosion comes from the Latin word "erosionem" which means "a gnawing away."
What are some examples of erosion?
They break up particles along the river bottom and carry them downstream. One example of river erosion is the Grand Canyon which was formed by the Colorado River. Waves - Ocean waves can cause the coastline to erode.
How does gravity affect erosion?
Gravity - The force of gravity can cause erosion by pulling rocks and other particles down the side of a mountain or cliff. Gravity can cause landslides which can significantly erode an area. Temperature - Changes in temperature caused by the Sun heating up a rock can cause the rock to expand and crack.
How does wind erode?
Wind is a major type of erosion, especially in dry areas. Wind can erode by picking up and carrying loose particles and dust away (called deflation). It can also erode when these flying particles strike the land and break off more particles (called abrasion). Erosion by Glaciers.
What causes erosion of the coastline?
Waves - Ocean waves can cause the coastline to erode. The shear energy and force of the waves causes pieces of rock and coastline to break off changing the coastline over time. Floods - Large floods can cause erosion to happen very quickly acting like powerful rivers. Erosion by Wind.
How has human activity increased the rate of erosion in many areas?
Human activity has increased the rate of erosion in many areas. This happens through farming, ranching, cutting down forests, and the building of roads and cities. Human activity has caused about one million acres of topsoil to erode each year. Erosion Control.
What are the giant rivers of ice that slowly move carving out valleys and shaping mountains?
Glaciers are giant rivers of ice that slowly move carving out valleys and shaping mountains. You can go here to learn more about glaciers . Living organisms - Small animals, insects, and worms can add to erosion by breaking up the soil so it is easier for the wind and water to carry away.
What diseases can cause colon erosion?
Colon erosions can result from many other diseases, including ischemic colitis (IC), Behcet’s disease, eosinophilic colitis, and pseudomembranous colitis. Share on Facebook Share on Twitter Share on Pinterest Email Print. Pagination. 1.
Where do you find a colon ulcer?
Ulcers caused by Crohn’s disease often crop up on the side of your colon near the mesentery, the tissue that holds your intestines to the inner wall of your abdomen.
What causes ulcers in the colon?
Colon ulcers have many causes. Where the ulcers are located in your colon may help diagnose the cause. Crohn’s disease and ulcerative colitis (UC). Both Crohn’s and UC are types of inflammatory bowel disease (IBD), an inflammation of your colon. These diseases can cause erosions or ulcers in your colon tissue.
What is the term for a small sore on the lining of the colon?
Colon erosions are small, shallow sores or ulcers on the lining of your colon, or large intestine. They’re often surrounded by a ring of red, inflamed tissue. They can also be irregular in shape, like long, ragged marks. You may hear these called rake ulcers or bear claw ulcers. While they don’t always cause long-term problems, ...
Overview
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 Earth's crust, and then transports it to another location where it is deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as physical or mechanical erosion…
Physical processes
Factors affecting erosion rates
The amount and intensity of precipitation is the main climatic factor governing soil erosion by water. The relationship is particularly strong if heavy rainfall occurs at times when, or in locations where, the soil's surface is not well protected by vegetation. This might be during periods when agricultural activities leave the soil bare, or in semi-arid regions where vegetation is naturally sparse. Wind erosion requires strong winds, particularly during times of drought when vegetatio…
Erosion at various scales
Mountain ranges are known to take many millions of years to erode to the degree they effectively cease to exist. Scholars Pitman and Golovchenko estimate that it takes probably more than 450 million years to erode a mountain mass similar to the Himalaya into an almost-flat peneplain if there are no major sea-level changes. Erosion of mountains massifs can create a pattern of equally high summits called summit accordance. It has been argued that extension during post-orogenic colla…
See also
• Bridge scour – Removal of sediment from around bridge abutments or piers by the movement of water
• Cellular confinement – Confinement system used in construction and geotechnical engineering
• Groundwater sapping
Further reading
• Boardman, John; Poesen, Jean, eds. (2007). Soil Erosion in Europe. Chichester: John Wiley & Sons. ISBN 978-0-470-85911-7.
• Montgomery, David (2008). Dirt: The Erosion of Civilizations (1st ed.). University of California Press. ISBN 978-0-520-25806-8.
• Montgomery, D.R. (8 August 2007). "Soil erosion and agricultural sustainability". Proceedings of the National Academy of Sciences. 104 (33): 13268–13272. Bibcode:
• Boardman, John; Poesen, Jean, eds. (2007). Soil Erosion in Europe. Chichester: John Wiley & Sons. ISBN 978-0-470-85911-7.
• Montgomery, David (2008). Dirt: The Erosion of Civilizations (1st ed.). University of California Press. ISBN 978-0-520-25806-8.
• Montgomery, D.R. (8 August 2007). "Soil erosion and agricultural sustainability". Proceedings of the National Academy of Sciences. 104 (33): 13268–13272. Bibcode:2007PNAS..10413268M. doi:10.1073/pnas.0611508104. PMC 1…
External links
• The Soil Erosion Site
• International Erosion Control Association
• Soil Erosion Data in the European Soil Portal
• USDA National Soil Erosion Laboratory