By Harry Cooper
Wind erosion is a type of erosion much like water erosion or splash erosion. It is a natural process for that helps shape rocks and other natural features in the environment.
Wind erosion occurs as wind moves tiny sand and dirt particles across the landscape. The process is slow and gradual, but over time it can move massive amounts of earth.
There are several different natural features on the landscape shaped by the wind. These features are called aeolian features.
Some aeolian features are less permanent and constantly shifting, such as desert sand dunes and coastal dunes. However, others are shaped by the wind over long periods of time, such as loesses, ventifacts, and yardangs.
Is Wind Erosion A Natural Process?
Wind erosion is normally a natural process. However human interference has exacerbated erosion in many parts of the world.
Harmful agricultural practices such as overgrazing and land clearing has led to severe wind erosion. This erosion has caused dangerous dust storms, decreases in agricultural productivity, and an overall decrease in air and water quality.
Increased wind erosion is just one of the many environmental consequences of extensive human land use. If we want to solve issues such as wind erosion, we need to find ways to farm and use land with minimal disturbance to the natural landscape.
How Wind Erosion Works
There are a variety of factors that contribute to wind erosion. The size of soil particles, soil moisture, wind speed, and ground cover all affect how intense and impactful wind erosion will be. The strength of the erosion is also used to divide wind erosion into different categories.
Types of Wind Erosion
Surface creep is the weakest kind of erosion caused by wind. This kind of erosion consists of soil particles usually 0.5 mm to 2 mm being dislodged and moving across the Earth’s surface without being suspended in the air, and traveling usually no more than a few meters.
Saltation consists of the movement of loose particles between 0.05 mm and 0.5 mm. During saltation, particles bounce along a surface material and often break down into smaller particles.
The most intensive type of wind erosion is suspension. Suspension involves incredibly fine particles of soil, sand, and clay being lifted into the air and often traveling several kilometers or forming dust storms.
Human Activity Affecting Wind Erosion
Wind erosion is a part of the natural forces that shape our world. For thousands of years wind has helped cycle nutrients, make landforms, and move Earth.
However, while wind erosion may be a natural process, human activity has made many kinds of erosion an ecological problem. One of the more predominant of these human activities is agriculture.
Agriculture and Erosion
Human populations have grown exponentially in the last couple of centuries. This has created an increasing need for food and agriculture.
This has caused humans to convert more and more land for farming. However as land is converted for agricultural use, it becomes more vulnerable to soil erosion.
As land is converted for farming, natural environments such as forests and grasslands are removed, and soil is tilled to make way for planting crops. This process removes roots, nutrients, and microorganisms from the soil making it much less complex.
Without its complex structure, the soil becomes loose and dry. This creates the perfect conditions for soil erosion, and makes natural erosion processes that much more intensive.
This alteration of the land has enabled wind to cause erosion at a much larger scale. It is estimated that human activity has caused a huge amount, almost half of Earth’s topsoil to be lost within the past 150 years.
Impacts of Wind Erosion
When wind erosion gets out of hand it can have a variety of negative impacts. These impacts not only affect the environment, but have consequences for all living organisms and humans as well.
One of the most immediate affects of wind erosion is an increase of soil particles in the air. This can manifest as harsh dust storms, travelling long distances, when there are high winds, or a general increase in air borne dust, soil and other particles in regular wind conditions.
Dust storms are large clouds of sand and dust particles that sweep across the landscape at high speeds. This damages plants and commercial crops with their abrasive dust particles.
Dust storms can also be economically harmful. This is due to their ability to cause environmental damage which disrupts transportation and damages infrastructure.
More dust and sand particles in the air also decreases general air quality. People living in areas with more particles in the air are at greater risk of developing asthma and other lung related health problems.
In addition to polluting the air, wind erosion also causes water pollution. When soil particles in the air get deposited in water it causes a serious decrease in water quality.
An influx of soil particles in water can clog streams and even powerful rivers. This interferes with the natural flow of water and disrupts the water cycle
Soil deposited into water bodies can also carry an excess amount of pollutants into the water. This can make it undrinkable for humans and unlivable for aquatic animals.
Along with these negative affects, wind erosion can also impact agriculture by stripping away layers of fertile soil. Thus, excess farming not only causes wind erosion, but is also impacted by it, creating an environmentally devastating feedback loop.
Preventing Wind Erosion
Wind erosion is most severe in places where soil is uncovered, loose, and dry. This allows for particles to be easily moved by the wind.
One of the best ways to prevent areas from having these conditions is by growing plants. By keeping an area covered in vegetation the soil is protected from the wind and held together by complex root systems.
While one could argue that farming is a good way to keep an area covered in vegetation, that is not necessarily the case. Farming requires a lot of tilling and soil disturbance which promotes soil erosion.
A recent study out of Northern China analyzed the best ways to prevent wind erosion. What it found was that the best way to prevent wind erosion is to leave the land alone.
Leaving an area untouched by human interference allows for plants to grow without human caused soil disturbance. This creates a sturdier soil that is more resistant to erosion.
While leaving the land to grow undisturbed would be ideal, we still need a certain amount of agricultural land to grow our food. But while farming may be counterproductive to preventing erosion, there are a variety of no till farming techniques that leave soil less disturbed and help prevent erosion.
Religion and Wind Erosion
Perhaps one of the best strategies for preventing erosion can be found in the Bible:
Six years you shall sow your land and gather in its yield; but in the seventh you shall let it rest and lie fallow. Let the needy among your people eat of it, and what they leave let the wild beasts eat. You shall do the same with your vineyards and your olive groves. (Exodus 23:10-11)
Letting the land lie fallow periodically gives the Earth the chance to heal. Just like we need to time to rest on the weekend, at night and on vacations, the Earth also needs time to heal. May we give the Earth the time she needs to heal, before she will take it for herself.
* Featured image source
