Home ›› 14 Dec 2022 ›› Opinion
(Part-II)
Soil forms from fresh parent material through various chemical and physical weathering processes and SOM is incorporated into soil through decomposition of plant residues and other biomass. Although these natural soil building processes regenerate the soil, the rate of soil formation is very slow. For this reason, soil should be considered a nonrenewable resource to be conserved with care for generations to come. The rate of soil formation is hard to determine and highly variable, based on the five factors of soil formation. Scientists have calculated that 0.025 to 0.125 mm of soil is produced each year from natural soil forming processes. Because of the time required to generate new soil, it is imperative that agricultural practices utilize best management practices (BMPs) to prevent soil erosion. The soil which is first eroded is typically the organic and nutrient enriched surface layer which is highly beneficial for plant growth. Thus, the primary on-site outcome is reduced crop yield as only the less fertile subsurface layers remain. Soil erosion also pollutes adjacent streams and waterways with sediment, nutrients, and agrochemicals creating serious off-site impacts.
Historically, conventional agriculture has accelerated soil erosion to rates that exceed that of soil formation. Erosion is often accelerated by agricultural practices that leave the soil without adequate plant cover and therefore exposed to raindrop splash and surface runoff or wind. Throughout human history, soil erosion has affected the ability of societies to produce an adequate food supply. Implementation of agricultural best management practices (BMPs), and through the practice of conservation agriculture, the rate of soil loss can be reduced to approximately equal the rate of soil formation. In addition to soil erosion, intensive land use has resulted in deforestation, water shortages, and rapidly increasing desertification of vast areas of the globe, all of which threaten the sustainability of our agricultural systems.
Sustainable Soil Management to Maintain Soil Health
It is evident that, in order to maintain and increase food production, efforts to prevent soil degradation must become a top priority of our global society. Current population models predict a global population of between 8 and 10 billion in the next 50 years and a two-fold increase in food demand. If mismanagement of soil resources continues to diminish the fertility of the soil and the amount of productive arable land, then we will have lost a precious and essential pillar of sustainable agriculture. Sustainable agriculture is an approach to farming that focuses on production of food in a manner that can be maintained with minimal degradation of ecosystems and natural resources. This sustainable approach to agriculture strives to protect environmental resources, including soil, and provide economic profitability while maintaining social equity. The concept of sustainable agriculture is often misinterpreted to mean that chemical fertilizers and pesticides should never be used. This notion is incorrect, as sustainable agriculture should embrace those practices that provide the most beneficial services for agroecosystems and encourage long-term production of food supplies in a cultural context of the region. It cannot be overstressed that sustainable practices should not only consider crop production and profit, but must include land management strategies that reduce soil erosion and protect water resources. By embracing certain modern-day technologies, proven BMPs, and learning from the past, our society will be able to continue to conserve soil resources and produce food supplies sufficient to meet current and future population demands.
Soil Improvement through Regenerative Agriculture
Regenerative agriculture is a conservation and rehabilitation approach to food and farming systems. It focuses on topsoil regeneration, increasing biodiversity, improving the water cycle, enhancing ecosystem services, supporting bio-sequestration, increasing resilience to climate change, and strengthening the health and vitality of farm soil.
Regenerative agriculture is a growing movement in agriculture as the need to improve or maintain the quality of topsoil has come to the fore. Soil health has a vital impact on not only improving the quality and quantity of the food produced, but also healthy soil makes the plants more resilient against extreme weather and pests. Taking care of the soil can reduce the level of inputs required for a given amount of quality produce.
As part of this regenerative agriculture or Regenerative farming approach, some farms adopt a “no-till” or “reduced till” approach to soil management with the idea being to reduce the amount of disruption to the soil. There is evidence that reduced tilling provides many benefits such as reduced soil erosion, Improved soil structure, helps build soil organic matter and so on. Also it reduces the cost of labor, fuel and equipment that would otherwise go into the tilling process.
Regenerative agriculture is not a specific practice itself. Rather, proponents of regenerative agriculture use a variety of sustainable agriculture techniques in combination. Practices include recycling as much farm waste as possible and adding composted material from sources outside the farm. Regenerative agriculture on small farms and gardens is often based on philosophies like permaculture, agroecology, agroforestry, restoration ecology, key line design, and holistic management. Large farms tend to be less philosophy driven and often use "no-till" and/or "reduced till" practices.
Regenerative agriculture looks to not only stop damaging our ecosystem but actually improve it, all while continuing to produce our food, fiber, and fuels. Regenerative Agriculture does not have a single, agreed-upon definition. However, most people would agree that it focuses on improving soil health by moving carbon from our atmosphere back into our soils using a variety of agricultural management practices that work in alignment with natural systems.
These are not “new” practices. Indigenous cultures have been interacting with nature in a restorative, reciprocal manner for thousands of years. We have the opportunity to blend indigenous wisdom with science and rapidly transform the way we practice agriculture around the globe, creating an abundant future instead of one of scarcity. We need to remember that we are nature and not separate from it, and how we treat nature has profound effects upon our society and the earth. As soil health improves, input requirements may decrease, and crop yields may increase as soils are more resilient against extreme weather and harbor fewer pests and pathogens. Most plans to mitigate climate change focus on "reducing greenhouse gas emissions." Regenerative agriculture, i.e. the capture of atmospheric carbon dioxide by growing plants that move that carbon dioxide into the soil, is pretty nearly the only currently-functioning technology available for drawing down greenhouse gases that are already in the atmosphere, mostly through the cultivation and nurturing of forests and permanent perennial pastures and grasslands. Regenerative practices that can reduce erosion and even build topsoil by improving the amount of carbon stored in the soil can have a significant impact on a farmer’s bottom line.
Farmers know they can make more money by improving yield, improving quality, raising prices, and reducing production costs, but how can any or all of these be accomplished by regenerative practices? A deeper understanding of how soil functions within the ecosystem are critical to becoming more profitable. Regenerative agriculture practices focus on improving soil health and biodiversity, by protecting the soil from erosion and increasing the number of carbohydrates (food) that get pumped into the soil via plant exudates. Because healthy soil can infiltrate and store more water, farmers can still get yields even when there are droughts and they can save money on irrigation costs.
Healthy soil makes more nutrients available to plants, which means less money needs to be spent on fertilizers. Healthy soils lead to healthier plants, which means farmers are less likely to need expensive insecticides, herbicides, pesticides, fungicides, etc. Healthier plants should have healthier yields of more nutrient-dense food. Healthier plants also have longer shelf lives, and typically look and taste better, which can all help a farmer, earn higher prices for their product. Reducing tillage while improving soil health can also reduce equipment, labor, and fuel costs. Farmers can actually improve their soil health each year while improving their bottom line. However, change is possible with the help of emerging production technologies, offering more plant-based alternatives, and smarter supply chains. Communication, intelligent use of data and informed engagement with consumers are at least as important. This requires a change of mindset, government and private sectors with purpose will be ready to handle it.
(Concluded)
The writer is Executive Director of Cotton Development Board
