12 Different Types of Soil Erosion
Soil erosion is a serious environmental problem that negatively affects agriculture, water quality, and ecosystem stability. It takes place when the top layer of soil is removed human activities such as deforestation and poor land management, as well as by natural forces like wind and water. It’s important to understand the different types of soil erosion so that we can develop strategies to prevent it.
Table of Contents
What Is Soil Erosion?
Soil erosion is the movement of soil by water, wind, ice, or gravity, and may be accelerated by human activities like agriculture and construction. This condition has severe consequences on ecosystems and human societies, equally. In general, soil erosion affects soil fertility, agricultural productivity, water quality, and overall environmental health.
Topsoil is the most fertile layer of soil, which is rich in organic matter and nutrients. The loss of topsoil lowers the soil’s ability to support plant growth, which can lead to food insecurity and poor crop yields. Also, soil erosion contributes to water pollution, since eroded soil can contain pesticides, fertilizers, and other contaminants that contaminate water and harm aquatic life.
This erosion also contributes to global climate change. A soil erosion can carry away fine particles like clay and silt as well as soil organic carbon (SOC). When this carbon is exposed, it releases gases like carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), ultimately contributing to greenhouse gas emissions. These gases are contributing factors to global warming and climate change.
A damaged soil structure also can’t hold water or nutrients. This slows down plant growth, so less carbon is absorbed by plants. It’s a never-ending cycle of erosion and carbon release that’s damaging our planet.
Now, we will look at the different types of soil erosion in detail.
Types of Soil Erosion
There are various kinds of soil erosion everywhere. The most common types of soil erosion are splash erosion, sheet erosion, rill erosion, gully erosion, tunnel erosion, bank erosion, wind erosion, glacial erosion, thermal erosion, chemical erosion, biological erosion, and saltwater erosion. Let’s take a look at them in more detail:
Splash Erosion
Splash erosion occurs when raindrops hit the soil surface with enough force to break up soil particles, causing them to splash and disperse. When raindrops fall, they hit the ground at high speeds, acting like little hammers, breaking and scattering soil particles. When raindrops that are bigger in size, they have more energy and displace more soil, so their energy depends on size and speed. On flat ground, particles are splashed in all directions. On slopes, more particles move downhill, which speeds up soil particle transport.
Splash erosion contributes substantially to soil degradation. By breaking down soil structure, it makes water harder to absorb, leading to more runoff and erosion. When this happens, topsoil is at risk, crops are less productive, and water bodies are sedimented, which can adversely affect water quality and aquatic habitats.
It’s important to keep the ground covered to prevent splash erosion. Raindrops will not directly hit the soil when it’s covered with vegetation, mulch, or other related coverings.
Also Check: Different Layers of the Earth.
Sheet Erosion
Sheet erosion takes place when rain hits the ground and the water flow gradually removes thin layers of soil. When rainfall forces soil particles out, water runs off the surface and carries them away. Every time it rains, this process repeats, slowly taking away more soil. Since the top layer of soil is removed in such small amounts over time, the changes are not immediately noticeable. It can take a while before the effects are clearly visible, which makes it a hidden form of soil erosion.
There are a lot of nutrients and organic matter in the topsoil, and in the absence of it, soil fertility decreases, which makes it more difficult for plants to get nutrients. Poor soil quality also reduces agricultural productivity, which leads to lower crop yields and less food.
Plants and grass protect soil particles from raindrop impacts (act as ground cover) and reduce surface water flow, preventing soil particles from being washed away. Soil disturbance can also be minimized through reduced tillage or no-till farming, which helps keep soil structure and reduces erosion.
Rill Erosion
Rill erosion happens when rainwater gathers and flows in certain paths, forming tiny channels called rills. They form when surface runoff gets strong enough during heavy rains to cut out small paths in the soil. Rill erosion takes away a large amount of soil quickly and is quite noticeable, instead of taking off a thin layer like sheet erosion.
The rills can easily remove large amounts of soil, reducing the soil depth overall. Most of the soil that gets carried away is nutrient-rich, thus soil quality suffers and crops grow poorly. It can even make the land more prone to further erosion and instability when channels are created by rill erosion. Plants also have trouble growing in the remaining, less fertile soil.
If the land is less steep, water will flow slower, reducing the chance of rills. You can also slow down water flow by keeping plants or grass on the soil. If you plow along the land’s contours instead of up and down slopes, water flow slows and reduces concentrations in one place.
Also Read: What is Soil Profile and How is Soil Formed?
Gully Erosion
This type of soil erosion happens when tiny channels (rills) turn into much bigger channels (gullies), which can’t be repaired with traditional farming techniques. When water flows in one spot, it can create big channels in the soil. Gully formation occurs when the flow of water becomes concentrated. A concentrated flow can happen because of high rainfall, water flowing from nearby areas, or water gathering in specific areas, like vehicle tracks or furrows (a plough’s narrow trench).
Whenever a gully forms, it can keep growing with each new rain, causing soil loss and changes to the landscape. Gullies are a lot larger than rills and can be challenging to farm. It can damage or destroy crops because it loses soil. Overall, it makes fields difficult to manage.
Planting cover crops can help your soil retain moisture, reduce runoff, and improve the soil structure. Building terraces and planting grass in water channels can help catch and redirect water. The soil will stay in place and water will flow slower. Regularly check and fix any damage to terraces and grassed waterways to prevent gullies from forming.
Tunnel Erosion
This type of erosion happens below the ground, when water creates hidden channels that carry soil away with it. You normally don’t notice tunnel erosion until it causes major problems, most notably sudden ground collapse.
It takes place when water finds a way to enter the soil through weak parts, such as cracks or old decayed roots. As water flows through these paths, soil particles are gradually removed, making the tunnels grow larger, and causing the ground above to become unstable. And eventually, the tunnels become too big and can’t support the ground above, causing it to collapse, which results in sinkholes.
Sinkholes are large holes that suddenly appear in the ground when the surface collapses. They happen due to natural erosion or human activities such as drilling and mining. Sinkholes can pose a threat to people, livestock, and farm equipment.
Overall soil structure is weakened by tunnel erosion. There’s less stability in the soil and it may also hold less water, which means plants won’t be able to grow well.
Groundcover keeps soil in place and stops water from entering vulnerable areas. You can also use gypsum to modify soil properties. It can reduce the spread of clay particles, helping to keep the soil more stable and less likely to create tunnels.
Bank Erosion
Bank erosion takes place when soil at the edges of rivers or streams gets carried away by water. While this erosion can occur naturally along rivers, it can also be triggered by heavy rain and also by human activities like cutting down trees and constructing buildings near rivers.
How Does It Happen?
Fluvial Erosion: Flowing water directly washes away soil particles from riverbanks. How much soil is eroded depends on how fast water flows and how hard soil is.
Mass Failure: It happens when the soil’s weight exceeds its strength, causing it to collapse into a river. River banks are more likely to collapse if they’re weakened by fluvial erosion.
It can result in land loss. This kind of soil erosion can wash away valuable land. There’s a possibility that roads, bridges, and homes around rivers will be damaged or destroyed because of bank erosion. It can also affect water quality (dirty water) and harm aquatic life (fish and other creatures) if there’s more soil in the water.
You can reduce this erosion by planting locally grown vegetation along riverbanks. The use of soil bioengineering techniques like using living plants such as willows rooted in the soil also stabilizes the soil both immediately and over the long run. Also, installing and using structures such as riprap (rocks) and gabions (wire cages filled with rocks). They help protect the banks by absorbing and deflecting water.
Wind Erosion
Wind erosion takes place when strong winds blow away loose soil particles. It mostly happens in dry, uncovered areas with little vegetation. Since here, the soil is loose and unprotected, areas with little rain are most affected.
When the wind blows, soil particles are broken up and detached from the soil’s surface. Detached soil particles are lifted into the air and transported over long distances by the wind. Even the tiniest particles can travel hundreds of miles. Land degradation and soil loss happen when the particles settle back to the ground, often far from where they started.
The loose structure of sandy or loamy soils makes them more prone to wind erosion. Dry soils are more prone to wind erosion because they lack moisture cohesion.
The process leads to desertification and reduced makes it hard to grow things. When the top layer of soil gets blown away, the soil loses its fertility. Dust from wind erosion can cause problems for human health and making it harder to see. A windstorm of sand can physically damage crops through blowing and burying them under layers of sand.
Maintaining vegetation cover and planting cover crops reduce wind erosion by stabilizing the soil. As plants hold the soil in place and keep it protected. You can also reduce wind speed and protect soil by building barriers: Trees, shrubs, and artificial structures slow down the wind.
Also Read: Soil Pollution: Causes, Effects, and Prevention.
Glacial Erosion
When glaciers move over land, they scrape, pluck, and erode the terrain they traverse. Therefore, glaciers, which are large masses of moving ice, wear away soil and rocks.
There are several ways glaciers do this, such as abrasion, plucking, and quarrying. In abrasion, glaciers scrape the ground. In plucking, glaciers grab rocks. And in quarrying, they remove bigger rocks.
There are a lot of landforms created by these actions, like U-shaped valleys, cirques, hanging valleys, sharp ridges (ridges), pointed peaks (horns), and hills called roche montagnenés. Glacial erosion changes landscapes significantly, forming mountainous regions and preserving evidence of glacial movements.
Thermal Erosion
Thermal erosion takes place when the permanently frozen ground (permafrost) melts because of warmer temperatures or heat from human activities. In cold regions, this melting can cause the ground to collapse and erode.
Natural events like wildfires, climate change, and human activities like building roads and mining can all melt permafrost. There are many effects associated with the melting of permafrost, including landslides and damage to buildings and roads. Also, melting can cause more soil erosion, which can wash away fertile land.
By monitoring permafrost temperatures, building insulated buildings, and keeping vegetation, we can prevent thermal erosion.
Chemical Erosion
Chemical erosion happens by altering soil and rocks’ composition because of some chemical reaction. This includes acidification, where acid rain deteriorates minerals; leaching, where water washes nutrients out; and dissolution, where minerals are dissolved in water.
Impacts from chemical erosion include soil degradation, which reduces soil fertility; water pollution, which hurts the ecosystem and health; and damage to structures like buildings. Plantation of vegetation, liming soil, and minimizing the use of harmful chemicals can help prevent the erosion of chemicals.
Biological Soil Erosion
Biological soil erosion is a continuous process that involves the activity of living organisms: animals, plants, fungi, and bacteria that act to mix and mineralize soil. The loosening and digging of the soil by animals or the breakage of the soil structure by plant roots and microorganisms decomposing matter are some of the processes that can change its structure.
Such erosion assists the recycling of nutrients essential for plants. On the other hand, it may make the soil loose and hence easily carried off by water or wind. The effectiveness of this soil cover is enhanced by increasing vegetation, minimizing soil disturbance, and reinforcing the soil by adding organic matter.
Saltwater Erosion
Saltwater erosion is caused when saltwater moves into areas that are near the coast, affecting the soil and water quality in an adverse way. Mainly, their causes are rising sea levels, storms, and over-extraction of groundwater. Indulgence of saltwater over freshwater creates saltiness in the land and breaks its structure with harm to tiny organisms.
This widens the challenge to grow crops, especially those intolerants to high salt levels. Salty waters contaminate freshwater sources, making them undrinkable and unacceptable for watering plants. We can beat this condition by checking the salt level in the soil and that of the water, putting a barrier to keep the salty water out, wisely using underground water, and planting crops that grow in salty conditions.
Also Read: How to Prevent Soil Degradation?
Conclusion
In the end, we have discussed different types of soil erosion, like wind, rill, gully, etc. Its a serious problem that affects environment and our land. The best way to protect our soil is to plant more trees, use better farming methods, and reduce activities that destroy it. If we’re aware of how soil erosion affects the earth and its environment, we can work together to preserve the soil for our future generations.