Restoring soil health in the age of climate change

Renewing and restoring soil health is integral to efforts to address food security challenges and ensure the revitalisation of our planet. When one looks at what one eats and how it is grown, we find extensive evidence of damage to both the soil and the larger environment. This points to an urgent need to change the way we produce and consume food. Only then will we be able to address global challenges such as climate change, soil health, the agrarian crisis, biodiversity loss, and water scarcity and make progress towards achieving the Sustainable Development Goals (SDGs).

Declining soil fertility continues to hinder agricultural production, prompting an evaluation of the strategies used by the farmers. Large tracts of agricultural land are losing fertility due to misuse or overdependence. Experts expect a 40 per cent loss of agricultural land in the next 50–60 years, by which time there will be about a 30 per cent increase in the world population. It is not too late to make a difference. Through ‘transformative change’, nature can still be conserved, restored, and used sustainably. Here are some stories from the field that have the power to suggest that positive outcomes are possible if we act on time.

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In the 1970s, Sarvadaman Patel, of Gujarat, was keen to implement his learnings from his Master’s degree in agronomy from the University of Wisconsin Madison (USA) in India and took the brave decision of returning to India to pursue farming. Over time, he noticed the negative consequences of chemical farming on his property and started looking for alternatives. Peter Proctor, considered the father of biodynamic farming, helped Sarvadaman Patel farm his land according to biodynamic principles. The transformation process was very slow, and it took him nearly 12 years of following the ground cropping techniques and mulching the soil to increase the soil organic matter content to about 1.42 per cent.

The quality of the soil has improved, and his produce also stays fresh longer. Every 0.5 per cent corresponded to an approximately fourfold increase in water absorption. His farm’s fertility steadily increased since the native breeds of cattle he maintained gave him a steady supply of dung to make good compost. Many crops, including cluster beans, sorghum, sunhemp, and cowpea, grown regularly in his field increase the nitrogen-fixing capacity of the soil. Green manuring crops are recommended on vacant lands to prevent soil carbon from escaping. Applying leaf litter helped increase the soil’s organic matter content. The waste from producing biogas, called bioslurry, is also used as fertiliser since it has a great capacity to sequester carbon. Each patch of land has a different microclimate, and land preparations need to be done differently with great thought and cost-effective techniques according to the crops grown during the season.

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Babuji Janakirajan of Coimbatore observed the adverse effects of chemicals on his coconut farm and noticed the soil was unpromising, with very little topsoil remaining and the organic matter being less than 0.5 per cent. Based on his observations, he felt an urgent need to do things differently. He followed nature’s path and introduced a wide diversity of plants, thereby restoring the mix of flora, fauna, pollinators, and microorganisms back to his farm. He has been consistent with his efforts to bring back forest-type ecosystems, with 350 coconut trees and 1,500 other species of timber and fruit trees on his land. He successfully reestablished nutrient recycling and conservation of water. Trenches were dug where water and chopped tree branches were recycled. The forest-type floor had heavy mulching. Six years since adopting transformation practises, his coconut farms have yielded in abundance, along with the other fruit trees, without disturbing or damaging the soil.

Sivakumar of Chennai encourages farmers to grow green manuring crops like legume crops, which can help revive soil fertility, improve soil structure, improve aeration, reduce pests and diseases, suppress weeds, and thereby increase the yield by 10-15 per cent and lower the fertiliser use of nitrogen. Green manuring crops are of short duration, fast growing and have high nutrient accumulation abilities. On the two-acre mango farm in Chennai, he has been raising green manuring crops like Crotalaria in the May-June season. The strategy involved here is to incorporate it into the soil by using a rotovator. After the monsoon showers in August, legumes like redgram and urad are regularly sown. Once the plants are harvested, they are then incorporated into the soil. These transformation practises are still done to upkeep the soil’s vigour and vitality. The results of the regular soil tests are proof that the soil is healthier and richer in organic matter content.

All these transformations show a critical need to move away from an input-heavy, yield-based food production system and return to locally adaptable crops growing in fertile soil, and these are truly inspiring. There needs to be critical analysis of the soil, credible sources to recommend bio-input recommendations to farmers for different regions and different crops, and awareness sessions too, since many are unsure regarding the credibility of their source. This signals an urgent need for systemic collaboration with institutions and research organisations to bridge the knowledge gap. Trials offering a piece of land on the campus of the ICAR institutes to farmers to conduct trials and creating a common platform for learning and sharing knowledge would be a great opportunity to understand the transformation better with the scientific fraternity.

Healthy ecosystems are crucial for sustenance on this planet. Even the act of producing food has had an impact on a range of aspects of the environment, particularly climate, biodiversity, soil health, water availability, and water quality. Our focus should be to work in diverse ways to achieve sustainable, equitable, and secure food systems for our continued survival on this planet along with the innumerable other species. A return to the local, sustainable agriculture-based restoration of our soils is inevitable to maintain the environment’s capacity to tackle biodiversity and nutrient issues at source but also to recreate the broken links of interspecies harmony that hold us together. Now is a good time to remember that “the EARTH does not belong to man, but man BELONGS to the earth.”

(The writer is the editor of Agriculture World)