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Soil Erosion Problems and Solutions

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Using Filter Fabric for Erosion Control

Filter fabrics, also known as geotextiles, are a type of fabric used to help prevent soil erosion and encourage plant growth. While many water filter fabrics are made out of synthetic materials, coir geotextiles have been rising in popularity.

Coir is a fiber extracted from the husk of a coconut shell. It’s tough, bacteria- and fungus-resistant, and biodegradable, making it a perfect material to use in gardening and erosion control applications. As it can be woven into a variety of different thicknesses and strengths, coir filter fabrics are easily customizable to your specific erosion control needs.

Benefits of Filter Fabrics

Land erosion is an international issue, impacting everyone from farmers to homeowners to businesses. With both significant droughts and major flooding causing erosion, it’s more important than ever to be prepared to protect your land.

Filter fabrics allow water to pass through while preventing sediment from flowing downhill or leeching into the water. By preventing dirt, stones, and other deposits from shifting, filter fabrics provide a stable area for plant life to germinate and grow. As plant life takes root, your need for filter fabrics will lessen; plants will provide natural erosion control.

Woven vs. Non-Woven Filter Fabrics

When choosing your filter fabric, it’s essential to select the fabric that would work best for your specific needs. Coir filter fabrics, for example, come in both non-woven mats and woven netting.

Different types of sediment call for different types of filter fabrics. Woven netting is best if you’re dealing with fine sediments, such as sand, or if you need something that can provide a lot of stability. Woven mesh is also great for suppressing weed growth in gardens.

Non-woven mats have a much higher flow-through rate but may allow small sediments to pass through. However, if you’re only dealing with larger sediment and have high water flow, a non-woven coir mat is likely your best option. Non-woven filter fabrics are also great for wrapping pipes or lining trench-style drains.

Using Coir as a Filter Fabric

It can be challenging to decide between synthetic filter fabrics and natural filter fabrics, especially as there’s more information about synthetic fabrics on the market. However, we strongly recommend using biodegradable materials like coir for many reasons:

  • Highly resistant to bacteria and fungus.
  • Not harmful to wildlife or domesticated animals.
  • Sustainable and natural.
  • Eco-friendly and requires little to no cleanup – will naturally decompose.
  • Available in a variety of strengths.

Coir filter fabrics have many benefits over more traditional filter fabrics, and may also be more cost-effective, depending on your needs. They can help filter water while preventing the displacement of dirt, seeds, and other vital parts of your landscape, and work equally well on slopes or flat lands such as gardens or drains. Whether you want to provide additional protection for a construction project or are trying to prevent further erosion issues on your property, coir filter fabrics are an excellent place to start.

Best Uses for Geotextile Fabric

Geotextile fabric is a type of material commonly used in construction and erosion control projects to improve the characteristics of the soil being worked with. This allows construction to take place in locations which might not otherwise be accessible.

Traditionally, geotextile fabrics are made of synthetic materials or combined with asphalt or other non-porous materials to increase their strength and filtration abilities. Non-woven geotextile fabrics are most commonly used to prevent groundwater pollution from construction projects and are also most commonly combined with asphalt, rubber, or other materials.

Geotextile Fabric Uses

Geotextile fabrics have several applied uses:

  • Protection – Geotextile fabrics are ideal for protecting easily eroded locations, including beaches. Their versatility means they can even be placed underwater if necessary, preventing erosion from wave currents.
  • Reinforcement – Heavier-density geotextiles can be used to reinforce weak or loose soil in construction sites or areas where the land cannot support agricultural growth on its own.
  • Filtration – One of the most common uses of geotextile fabric is filtration; that is, allowing water to pass through while keeping sediments from polluting natural water sources.
  • Separation – Most commonly seen in road construction, geotextile fabric is used to keep different types of soil from mixing. For example, a geotextile fabric layer may be placed between a coarse aggregate and a finer sub-grade aggregate, keeping the two separate and ensuring the stability of both.
  • Drainage – Another widespread use of geotextile fabrics is drainage. This is different from filtration, as geotextile fabrics used for drainage catch rainwater or other naturally produced water and diffuse it into the soil. This can help prevent flooding.

Using Coir as a Geotextile Fabric

Recent research into using coir, the fibrous part of a coconut’s husk, as a geotextile has shown promising results. Coir fiber is relatively strong and maintains water saturation, which can be essential in drier climates. It’s also cost-effective; the high supply of coir compared to the demand makes coir geotextile fabrics relatively inexpensive.

One of the most substantial benefits of coir as a geotextile fabric is its eco-friendly nature. As a biodegradable geotextile, it adds nutrients to the soil naturally over time while simultaneously encouraging plant growth. It’s resistant to rot, fungus, and bacteria that may otherwise damage or kill plant life, whether it be in your garden or as part of a comprehensive erosion control program.

When used in civil engineering projects, coir geotextile fabrics have been shown to have high durability and strength, resisting compression and adding value to the soil. Coir geotextiles have been used as part of the foundation of both paved and unpaved roads in India, and have also seen great success in slope erosion control and topsoil retention.

Whether you’re using coir on a personal level; for example, to keep your garden healthy and encourage moisture retention, or are hoping for a more eco-friendly alternative to the synthetic geotextiles that are currently available, we highly recommend exploring possible options for coir geotextile fabrics.

What is Land Degradation?

What is land degradation? Land degradation is a negative change in the quality of land, usually induced by a mixture of natural and man-made causes.

It affects the land’s topsoil, the vegetation that grows on it, and the nearby water sources. It is a global issue with millions of people being affected, even forcing them to relocate in some cases.

What Causes Land Degradation

In most cases, the main causes of land degradation are linked to one or more human activities. Deforestation is one of the most common activities that cause the degradation of land.

Forests play a big part in keeping the soil fertile by constantly feeding it with nutrients from fallen leaves and fruit, as well as from animal droppings. They also keep the soil’s structure in place with the help of the trees’ roots.

Therefore, cutting down a part of a forest is a clear path to land degradation.

Another major man-made cause of land degradation and development of unfertile soils is the overuse of pesticides and fertilizers. Although they have become indispensable to raising rich crops, excessive use is known to gravely deteriorate the affected land.

Certain natural nutrients within the soil become imbalanced as a result of overuse of fertilizers, with a negative long-term effect on the land. Good farming practices will always seek to balance the short-term gain of eliminating pests and growing bigger crops with the long-term downside of land degradation.

Overgrazing is another significant cause of land degradation. It usually occurs when livestock is fed on a limited patch of land and the grass and other vegetation in the area are not able to regenerate at a sufficient rate.

The resulting lack of vegetation deprives the land of much-needed nutrients, the result being the degradation of the soil. It is a major issue, especially in Africa, where the long-term grazing of livestock on small patches of land leads to rapid land degradation.

Salination is also a significant cause of land degradation. It’s defined by the increase of salt concentration in the soil; it can be either man-induced or a natural phenomenon.

A high salt concentration in water used for irrigation, excessive use of alkaline fertilizers, inadequate soil drainage, or simply the wind blowing the salt in areas near the sea are causes of land salination that leads to land degradation.

 “Land Degradation: Creation and Destruction,” by Douglas L. Johnson and Laurence A. Lewis, states that the main naturally induced causes of land degradation are wind and water erosion.

Wind erosion occurs in areas with little or no vegetation and sandy soil, so strong winds carrying soil particles deteriorate the land. Water erosion is the displacement of land either by water in motion or by heavy rains. It’s often caused by human actions like deforestation, but it can also occur naturally in situations such as heavy rain, causing soil displacement on a steep slope of land. 

Land Degradation Effects

The main effects of land degradation can be soil erosion, salinization, acidification, and alkalization of the land, and finally desertification. Land desertification is the most severe stage of land degradation. It means that a piece of land has lost all its vegetation, wildlife, and all its water supplies — it basically has been turned into a desert.

The first steps in recognizing the effects that land degradation has on the planet are understanding its causes and effects. Sadly, the effects can be felt all over the world. The countries that are most affected are usually the poorest, and the lack of crops and farmable land can lead to massive food shortages.

Also, as crops become less efficient, water sources also dry up, often leading to the mass migration of people to more hospitable lands.

The downward spiral caused by land degradation can lead to major socio-economic issues. As food and water become scarce, competition for the remaining resources increases.

In poor countries and isolated regions, this competition can often lead to a monopoly on vital resources, resulting in violent attempts to overturn such a monopoly.

Experts on land management Ephraim Nkonya, Alisher Mirzabaev, and Joachim von Braun, argue in their book, “Economics of Land Degradation and Improvement – A Global Assessment for Sustainable Development,” that degradation is also a significant health hazard to the populations in the affected areas.

Due to the relatively low standard of living in most such areas, the lack of food and water will often lead to malnutrition, as well as diseases caused by the lack of clean water and the resulting poor hygiene. If the population migrates, the risk spreads out, as certain infectious diseases can be carried by the migrating population to new lands.

How to Prevent Land Degradation

In order to prevent or reverse the effects of land degradation, a series of policies and management practices must be implemented. In areas where the degradation process is at its initial stages, it’s crucial that prevention practices are quickly put in place.

Prevention is significantly less expensive than trying to reverse the effects of land degradation. That’s why the first step in preventing land degradation is to properly inform the people in an endangered area about both the causes and effects of the phenomenon and also about the great danger of desertification.

As in most situations, properly preventing land desertification is a matter of avoiding the causes. Natural causes such as heavy rain or strong winds obviously cannot be avoided, but according to a report by the United Nations’ Economic and Social Commission for Western Asia on land degradation assessment and prevention, the man-made causes need to be better managed or eliminated in order to avoid land degradation. 

Deforestation must be kept to a minimum and always be followed by reforestation, in order to keep the land well bound and rich with the nutrients it needs.

Sustainable farming also needs to be practiced, with good management of the levels of pesticides and fertilizers used, as well as avoiding soil depletion because of overgrazing by livestock. 

Land degradation is an issue that should concern every country and every community. Although we have significantly evolved from a technological point of view, our survival still heavily relies on the quality of our lands, and that is especially true in poorer regions.

The decrease in soil quality not only affects agriculture but also creates a ripple effect of major socio-economic implications that affect the entire planet.

List of sources:

“Land Degradation: Creation and Destruction,”  Douglas L. Johnson, Laurence A. Lewis

“Economics of Land Degradation and Improvement – A Global Assessment for Sustainable Development,”  Ephraim Nkonya, Alisher Mirzabaev, Joachim von Braun

Land degradation assessment and prevention, United Nations Economic and Social Commission for Western Asia

Understanding Soil Stabilization

Soil stabilization is a term that denotes the physical, mechanical, biological, chemical, or combined method of changing natural soil for a specific purpose.

Soil may need to be stabilized in order to increase its weight-bearing capabilities or improve its tensile strength. Understanding the various types of permanent and temporary soil stabilization methods is essential for improving load-bearing capacities to support building foundations, road pavements, and other engineered structures.

The Importance of Soil Stabilization

Natural soil doesn’t always have the properties necessary to support construction projects. Unless the soil is stable enough to support a road or building, the structure can easily be washed away by flowing water, especially during a flood or torrential rainfall.

Soil that hasn’t been stabilized tends to contain larger particles than stabilized soil. These larger particles allow the soil to sink, which can result in literal sinkholes due to the soil’s inability to bear the weight of traffic.

With stabilized soil, the particles are crushed into smaller sizes, resulting in a compact soil that holds up well to manmade structures.

Types of Soil Stabilization

There are many materials and methods utilized in stabilizing soil, including:

  • Electricity.
  • Geotextiles.
  • Cement.
  • Lime.
  • Bitumen (asphalt).
  • Chemicals.

Electrical Stabilization

When electricity is used in soil stabilization, a direct current is sent through the soil in order to drain and discharge water. Draining the soil strengthens it, lowers the soil’s water table, creates an anti-seepage curtain, and provides stability to slopes, allowing construction to take place in slide-prone areas, trenches, pits, and quarries.

Electro-osmosis, however, is only used in soil stabilization when no other method is suitable. That’s because the process requires highly sophisticated and specialized equipment along with a high amount of electricity to achieve the desired result.

Geotextile Stabilization

Various types of geotextiles are frequently used in soil stabilization efforts. High-quality geotextiles like coir have been used to control soil erosion, support roads, improve drainage, and promote quick vegetation.

If you’re looking for a natural, eco-friendly method to stabilize soil, these versatile, permeable soil stabilization products are effective, low-cost options. Coir is a geosynthetic made from coconut fiber that can be synthesized for specific applications, allowing it to meet a variety of requirements.

Soil Cement Stabilization

Cement is often used as a low-cost means of preparing foundations for parking areas, highways, residential streets, and airport runways. The technique involves mixing soil with cement and water to form a strong soil-cement. Also known as a cement-treated aggregate base or cement-stabilized base, soil-cement can involve any type of soil and gravel rock combination.

Prior to construction, it’s important to perform laboratory tests to establish the soil’s water requirements, cement content, and compaction.

Testing ensures the soil-cement stabilization mixture has enough durability and strength to last. Soil-cement is made in a central mixing plant or on-site depending on the project, but there are always four steps involved:

  • Spreading cement.
  • Mixing.
  • Compaction.
  • Curing.

Curing is important for preventing water evaporation and ensuring maximum strength. In most cases, a light coating of bituminous material is used to prevent moisture loss.

Lime Soil Stabilization

Mixing lime with soil can significantly improve construction sites. When the right amount of lime is added to a reactive soil, the soil stabilizes and gains strength through a process called pozzolanic reaction. This chemical reaction converts a silica-rich soil with no cementing properties into a calcium silicate with excellent cementing properties.

In fact, the pozzolanic reaction was the main reaction involved in creating Roman concrete, which was used to build not only ancient roads but also impressive structures like the Pantheon.

Today, lime continues to be used as a trusted method of stabilizing soil via pozzolanic activity. The key is using a reactive soil along with a good mix design protocol to improve the soil’s strength and long-term durability.

Bituminous Soil Stabilization

Bitumen is a black viscous mixture used mainly in roofing and road surfacing. Most people know it as asphalt. The concept of bituminous stabilization is similar to soil-cement. Essentially, a controlled amount of bituminous material is added to soil and mixed to increase its load-bearing capacity and make it water-resistant.

Bitumen is sticky by nature, which helps it hold the compacted soil particles together. The result is a strong layer that prevents groundwater from being absorbed. As such, bitumen is excellent for waterproofing. 

Chemical Soil Stabilization

Chemical soil stabilization involves altering the soil’s properties via chemicals like chrome lignin, polymers, sodium chloride, sodium silicate, calcium chloride, and other chemicals. Chemical reactions can cause the soil’s structure to change, removing space between the particles and making it more compact, leaving no room for air or water to penetrate it.

Polymer soil stabilization is a popular chemical technique for geotechnical engineering, agricultural, and construction projects. Adding various polymers to soil can reinforce roadbeds, reduce erosion, support soil structure, increase soil shear strength, and improve water retention.

Soil Stabilization Equipment

Once you know which soil stabilization method to use, you’ll need to invest in the right equipment. Soil stabilization machines are designed with different approaches in mind, and each technique requires different equipment and machinery to get the job done. While your needs may vary, these are some of the most widely used soil stabilization machines.

Integrated Mixers

On sites where dust may pose an issue, an integrated mixer spreads a controlled amount of lime, cement, or other material directly in front of a mixing drum. The binding agent is immediately mixed with the site’s soil, eliminating dust issues and creating a stabilized soil on the spot.

Spreaders

Spreader units are either self-propelled or tractor-towed, but their purpose is to spread all sorts of dry binding agents. Although they’re often called cement spreaders, they can spread large quantities of fly ash, lime, cement, and similar materials with minimal dust.

Cold Planers

Cold planer machines are a low-cost option designed to grind asphalt. Also known as asphalt milling machines, cold planers feature rotating drums that remove and grind surface asphalt. The pavement can then be loaded on a conveyor and removed from the site or mixed with soil.

Reinforcing the soil provides the perfect foundation for a variety of engineering feats. When you choose the proper soil stabilization technique, you can rest assured your construction project will stand the test of time.

Sources:

https://www.civil-engg-world.com/2008/12/electrical-stabilization-of-soil.html

https://www.popsci.com/roman-concrete-can-withstand-seawater

http://article.sciencepublishinggroup.com/pdf/10.11648.j.ijtet.20170302.12.pdf

http://scholarsmine.mst.edu/cgi/viewcontent.cgi?article=3360&context=icchge

https://crrc.unh.edu/sites/crrc.unh.edu/files/media/docs/Workshops/liquid_asphalt/concawe_bitumen.pdf

https://www.mdpi.com/2073-4360/10/3/287/htm

http://asphaltzipper.com/how-it-works/road-repairs/soil-stabilization

https://www.wirtgen.de/en/technologies/application/recycling-soil-stabilization/soil-stabilization/bodenstabilisierung.php

http://precisioncoldplaninginc.com/services/soil-stabilization

The Causes and Effects of Soil Erosion

Soil erosion is a type of soil degradation that naturally occurs on all land. There are many causes of soil erosion, most of them being the same as other forms of erosion: namely water, ice, wind, and gravity. The effects of soil erosion can include the loss of fertile land to floods or water pollution, among others.

What Causes Soil Erosion?

According to geoscientist R. P. C. Morgan, soil erosion is usually caused by a mixture of events that naturally occur as well as the influence of human activity, having affected regions such as those bordering the Mediterranean Sea or China for millennia.

The largest cause of soil erosion cannot be linked to a single major event or activity. So which of the following events most contributes to soil erosion? There’s no straight answer, and each situation is different. 

Soil erosion is one of the side effects of heavy rain. Massive amounts of water can displace the top part of the soil, dispersing materials such as fine sand particles, organic matter, and silt. If the phenomenon continues over a longer period of time, even heavier sand and gravel particles will be displaced.

The most obvious and dramatic soil movement and erosion occur during short and intense thunderstorms. However, less intense but steady rainfall usually has the same effect, although it’s not as obvious.

Heavy farming is another major cause of soil erosion. Working the land by raising crops and through other agricultural activities will reduce the soil’s overall structure and the levels of organic matter within it, leaving it more vulnerable to the effects of heavy rain.

Tilling is the most significant farming-related factor in soil erosion, as the constant softening of the soil will enable erosion. An article published in Science Direct, “Evolution of the Plow Over 10,000 Years and the Rationale for No-Till Farming,” shows that farms where tilling is not used as a farming practice or is used sporadically, the chances of soil erosion significantly drop. 

Another major contributor to soil erosion is the physical shape of a particular piece of land. If the land is on an incline, the slope will facilitate the fast movement of water during rainfalls, oversaturating the soil and greatly contributing to its erosion.

Vegetation helps keep the structure of soils, so the lack of plants and crops on a piece of land is known to contribute to the acceleration of soil erosion. If an area of land is naturally less populated with plants, it can be seen as a clue regarding that particular area’s predisposition for erosion.

Wind is also known to greatly reduce soil quality and cause erosion, especially when paired with another erosion-facilitating factor. Light winds, however, do not do any damage to the soil structure. The types of soils most affected by wind are light and sandy soils, which can be easily lifted and transported onto other plains.

Facts About Human Soil Erosion

Human soil erosion is an ever-increasing factor in the overall erosion and degradation of land. Here are the most important human soil erosion facts:

  • According to recent studies, human activity causes as much as ten times more soil erosion than all the Earth’s natural processes combined. 
  • Studies made by University of Michigan geologist Bruce Wilkinson show that soil erosion caused by humans is by no means a new phenomenon. In fact, human influence on soil degradation, in general, can be traced back to the beginning of the first millennium. It is estimated that natural erosion affects about 60 feet of land every million years, while soil erosion in agricultural-heavy parts of the United States is estimated at 1,500 feet per million years, largely due to human influence. Other parts of the world show even higher erosion rates.
  • The effects of deforestation on soil erosion are also massive. Removal of trees without reforestation affects the planet in a number of ways and soil erosion definitely is one of them. First, trees provide the soil with valuable dead organic material, through leaves, animal droppings, and fruit that falls to the ground; all of these help the soil retain its shape. Also, deforestation exposes the soil to rainfall and its resulting effects on the soil. The tree roots also contribute to the overall structure of the soil, further linking deforestation and erosion.

How Does Soil Erosion Affect Streams and Rivers?

The effects of soil erosion stretch beyond the affected lands; they also damage streams and rivers. An article published in the Journal of Hydrology, “An Analysis of the Processes of Riverbank Erosion,” by J.M. Hooke, describes how land displacement causes increased sedimentation and pollution in running waters, clogging them and greatly affecting all the flora and fauna in the area, such as fish and other species.

It also limits the ability of affected rivers and streams to absorb larger amounts of water, increasing the chances of a flood during rains. The narrowing of river canals can also make boat navigation impossible. Soil erosion behind seawalls is also a major issue, as it can cause a seawall to fail, leading to property damage. 

Soil Erosion Effects

The effects of soil erosion can range from mild to catastrophic. The biggest effect is definitely the loss of topsoil, the fertile part of the land that can be used to grow plants. This alone can cause food shortages and famine in many parts of the world.

It also leads to further erosion, as the water won’t be as easily dispersed beneath the top part of the soil. Also, the lack of crops will reduce the organic nutrients in the soil, even more, leaving it barren for the long term.

Another major issue caused by soil erosion is possible water contamination and pollution. Since the water can’t be effectively absorbed by the land, runoffs will occur and carry fertilizer or pesticide with them.

The contaminated water can do further damage to the environment by poisoning and killing fish in nearby lakes and rivers. It also can make its way into sources of drinking water, becoming a real threat to the health of nearby populations.

Soil erosion is not a new problem for humankind, but it’s definitely a pressing one. Through careful farming and crop management, water control and drainage, as well as properly educating individuals about the dangers of soil erosion, the problem can gradually be eradicated and more fertile land will become available.

List of sources:

“Soil Erosion and Conservation,” R. P. C. Morgan

“Evolution of the Plow over 10,000 Years and the Rationale for No-Till Farming,” R. La, D.C. Reicosky, J.D. Hanson, Science Direct

“An Analysis of the Processes of Riverbank Erosion,” J.M. Hooke, Journal of Hydrology