OPINION: Soil - the unseen solution to food security and climate change

sexta-feira, maio 31, 2019

Joao Campari is Global Food Practice Leader at WWF International.

Feeding a growing global population and limiting the impacts of climate change are interwoven problems. We often hear of how stopping deforestation, changing how we eat and how we power our world, and reducing food waste, can improve the situation. But one thing that has not yet received due attention is preserving the health of our soils. Fertile soils act not only as a carbon store but are a necessity for sustainable agriculture. As 200 experts, policymakers and civil society representatives gather in Nairobi this week to discuss the importance of soils and rehabilitation as part of Global Soil Week, preserving and enhancing the quality of our soils is a must as we seek to solve some of the greatest challenge of our time.

Our soils contain two to three times more carbon than the atmosphere. This carbon-rich organic material helps retain water and essential nutrients for growing plants. Such agricultural productivity is closely correlated with the health of soils, for which sufficient organic matter is the main indicator. Stable and productive soils directly foster the resilience of farmers to cope with the effects of disruption in the climate - they are clearly important for human nutrition.

Yet our soils are suffering at an unprecedented rate. The Global Soil Biodiversity Atlas maps the potential threats to soil biodiversity across the globe. Unsurprisingly, the areas with highest risk are those with greatest exposure to human activities, including intensive agriculture.

Since the start of the industrial revolution, soil cultivation and the depletion of soil organic carbon has resulted in the release of as much as 4.4 billion tonnes of CO2 per year. It has been caused by, among other things, excessive tillage, lack of crop rotation and intensive agricultural inputs. In general, 50 to 70 per cent of soil carbon stocks have been lost in cultivated soils. Not only does this loss of carbon exacerbate climate change, it means a vanishing home for numerous species. A quarter of all life on earth can be found beneath our feet. Soil biodiversity encompasses microorganisms and microfauna as well as species like ants, termites, earthworms and moles. These underground organisms influence the physical structure and chemical composition of soils; they are essential for enabling and regulating critical ecosystem processes such as carbon sequestration, greenhouse gas emissions, and the uptake of nutrients by plants. Soil biodiversity is not only key to sustaining food production and other ecosystem services but also to detoxify polluted soils, suppress soil-borne diseases and contribute to the nutritional quality of food.

An increase in soil carbon stocks can be achieved by adopting agro-ecological practices, including nourishing soils with manure and compost, planting legumes and trees, and collecting water at the feet of plants.

In several countries, WWF is working with local farming communities to implement such practices and improve the health of their soils. For instance in India, where organic systems have been introduced to rehabilitate soils and enhance ecosystem services; and in Paraguay where the greenhouse gas emissions in beef and soy production are being reduced by improving soil health in the Chaco.

The challenge and imperative is to now implement such practices and improve soil health at scale. There are 570 million farms in the world and more than 3 billion people living in rural areas who could implement these practices. Education programs and technical upskilling initiatives will help farmers, but governments and financers must make it easy for them to be implemented. Policy measures must be established to encourage such agro-ecological practices, removing incentives for unsustainable practices, while financers must also begin to prioritize investing in agricultural projects which enhance soil health. To do so, a stream of bankable projects will need to be identified, which will require the collaboration of both the private and public sectors.

Beneath our feet rather than in front of our eyes, soils are too often disregarded and underappreciated. Now is the time for them to be truly valued. Healthy soils are fundamental for food security, limiting temperature rises and preserving biodiversity. Treated poorly, they will erode and dry, before literally blowing away in the wind. The consequences would be dire. We must restore the health of our soils to preserve our food system and, thankfully, sustainable agriculture practices themselves are a core solution.

Page: Thomson Reuters Foundation News