By Vikramjiet Roy,
Soil degradation is gradually becoming a major challenge in the world, and one of the biggest drivers of it is the erosion of topsoil. Soil degradation might just be coming to a tipping point if immediate action is not undertaken to contain the damage. Slow to develop, the problem could well have a domino effect, with multiple consequences at various levels.
The Challenge of Soil Erosion
Soil degradation and erosion are adding to the food, water and energy crisis. Soil is the source of 95% of the food that we consume. Hence, it can be said that almost all the bioenergy on the planet is rooted in the finite source called topsoil. It also impedes the scope of water infiltration and storage into soil, leading to water scarcity and waterlogging.
Furthermore, with soil supporting less vegetation and forestry, it will have a disastrous impact on our ecology, will hasten global warming and climate change, and will prove to be a huge impediment in global efforts for ecological restoration. Just how much soil erosion contributes to soil degradation in India can be understood from the fact that about 119.2 million hectare area in the country is impacted by soil erosion. It is estimated that soil erosion happens at the rate of 16.35 tonnes per hectare in India.
Understanding the Causes
It is commonly perceived that the long coastlines or river shores might be dragging the topsoil along. It must be noted that not always rivers and channels exert constant hydraulic forces on soil surfaces. While rivers do contribute to soil erosion and 29% of soil erosion is caused by sea, most of the soil erosion or topsoil movement, around 61%, is caused by other means, such as strong winds, heavy rains, and human activities. A range of human activities including deforestation as well as agricultural and infrastructural development malpractices contribute to the problem.
Transcontinental and national initiatives to promote soil conservation have gradually emerged as a regular focus area. Most initiatives focus on creating awareness, education, and policy advocacy on the subject. The ongoing Conscious Planet – Save Soil movement is a global environmental campaign, aiming to address the soil crisis by bringing together people from around the world to stand up for Soil Health, and supporting leaders of all nations to institute national policies and actions toward increasing the organic content in cultivable Soil.
Why Is Forestation Not Enough?
Although forestation or vegetation growth is largely effective, it is not highly reliable. This is because it would take considerably a longer time to get the kind of dense forestation that prevents soil erosion in the first place. Also, 100% vegetation cover across terrains is difficult to achieve. In hilly terrains, it is also highly unsuccessful. Vegetation may not survive and provide enough strength to the soil for a number of factors.
Nevertheless, forestation and vegetation growth should be employed aggressively for their many benefits and advantages in preventing climate change. There’s another alternative approach as well. Looking at the problem of soil erosion from the lens of sustainable growth and infrastructural development of an economy can provide us with sound engineering solutions suited for various terrains. Contrary to popular perception, the new-age engineering technologies can help roll out sustainable and infrastructure development measures for the conservation of soil.
Leverage Sustainable Engineering to Control Soil Erosion
In most soil erosion scenarios, unstable slope act as a key facilitator for the movement of soil powered by agents like flowing water or wind. There are some good engineering methods that can ensure erosion control. Slope protection is one of the effective measures to control erosion and contain the impact of erosion forces. Solutions such as erosion control mats(Geo mats) can be customized as per the needs of the terrain to suit the slope and make them effective against erosive forces.
Geomats are also known as Rolled Erosion Control Protection (RECPs) mats which are biodegradable mats (biomats) and synthetic mats. While biomats ensure immediate protection to vulnerable slopes to the effects of erosion such as wind, rain, and surface run-off, geomats are an effective solution for superficial erosion protection caused by the impact of raindrops and rills. One of the quickest and most efficient methods of building up vegetation is Hydroseeding. It’s a technique used on barren soil surfaces for soil adjustments and is effective in tackling soil erosion, controlling dust, and regrowing vegetation. This technique can be used standalone or in combination with geomats.
Tailor-made engineering solutions like MacWeb, a cellular containment system designed to deliver erosion control are used to secure a layer of topsoil and promote the growth of vegetation on surfaces that would otherwise not sustain grass or plants (e.g. steep or “rocky” slopes).
For Hydraulic and erosion protection works, mattresses crafted like a cage and engineered from mechanically woven double twisted steel wire mesh are effective in controlling and preventing erosion on the river banks. These mattresses are made from high quality steel wire, which is heavily galvanised to provide corrosion protection. An additional protective polymeric coating is also applied which is used in aggressive environments, or where a longer design life is required.
Modern engineering can provide better solutions to several challenges faced by mankind. With a massive landmass and various terrains, using scientific innovation and superior engineering approaches will help India protect its land by controlling soil erosion. These methods are not a replacement of traditional approaches toward mitigating the loss of topsoil. Rather, they can be simultaneously implemented to rollout a long-term solution for this age-old problem.
(The author is Managing Director, Maccaferri India. Views expressed are personal and do not reflect the official position or policy of the FinancialExpress.com.)