How Caring for Our Soils Helps Fight Climate Change
This post was written by Katrin Glatzel, a policy and research officer at Agriculture for Impact. There, she leads the research and writing of the Montpellier Panel Reports and Briefing Papers, as well as the team’s research work around sustainable intensification.
As the International Year of Soils comes to an end, the Sustainable Development Goals (SDGs) have been passed and COP21 is wrapping up in Paris, it is time to reflect on the role soils can play in future development agendas.
The decision made at the Rio+20 conference to develop a set of SDGs and the agreement “to strive to achieve a land degradation-neutral world in the context of sustainable development” created momentum to discuss the role soils play in the global sustainable development agenda. It also initiated discussions concerning the need to develop clear soil and land indicators, necessary implementation mechanisms, supporting governance instruments, and the role of public participation.
This is now, at least partially, reflected and anchored in SDG goal #15, “Sustainably manage forests, combat desertification, halt and reverse land degradation, halt biodiversity loss.” Furthermore, the French government’s “4 per 1000” initiative, submitted in spring 2015, is aimed at making agriculture a solution in addressing climate change while advancing food and nutrition security. Specifically, it is based on the premise of sequestering atmospheric carbon in the world’s soils at the rate of 0.4 percent a year.
Smallholder farmers are part of the solution
The “4 per 1000” initiative seeks to compensate for the total annual carbon emissions of more than 9Gt (that’s gigatons!) through a global program. Agronomic techniques, such as those under the heading of Sustainable Intensification, can help deliver carbon sequestration at an average rate of four-thousands of the carbon stock in the soil. This means that smallholder farmers can be (and are) part of the solution to climate change through their willingness to adopt new agricultural practices that bring multiple benefits in the short and long terms. This willingness must be appropriately encouraged; it requires strong political leadership and substantial investment in infrastructure, education and training, and the provision of new technologies.
Improved land management can help farmers adapt and has important co-benefits for mitigation.
Improved land management practices will not only make farmers more resilient in the face of weather shocks and climatic stresses—it will also significantly contribute to benefits for mitigation of climate change. Globally, the soil contains about 1500Gt of organic carbon, more than double the amount of carbon in the atmosphere and three times that in plants, animals and micro-organisms combined. The cumulative historic loss from ploughing and mining the soil’s humus is between 50Gt and 78Gt. However, carbon sequestration (adding more organic matter to the soil than decays) can help minimize greenhouse gas emissions. Agroforestry systems, for example, can capture carbon in the range of 2-4 tons per hectare per year—an order of magnitude higher than conservation farming.
In practice, effective sequestration depends on the technologies, the soil texture and structure, climatic conditions, the farming system and associated practices of soil management. While there are many successful small-scale projects, taking sequestration to scale can be rather challenging. There are difficulties in measuring both the pre-existing carbon in the soil and ongoing levels. As a consequence, technical skills are essential but often limited. There are also likely to be significant institutional barriers linked to issues such as determining land rights, monitoring and ensuring compliance and, finally, paying farmers for sequestering carbon in their soil—payment for ecosystem services (PES).
Setting the right incentives
Farmers can and will undertake actions that have co-benefits for mitigation, but they need to be provided with the right incentives such as PES, land rights, improved knowledge and training. Payments to farmers or landowners to better manage their land or watersheds, to conserve biodiversity or to sequester carbon have been shown to help conserve and restore forest areas and aquifers.
For example, in order to improve soil quality and to support local livelihoods, Niger has embraced a set of wide-ranging approaches that has helped restore arable land and increase farmers’ capacity to withstand droughts. With no incentive to maintain trees on their property—and with families to feed—farmers in need of agricultural land regularly removed trees and other natural vegetation across the country. This led to worsening soil erosion and reduced soil fertility and yields, which pushed farmers to cultivate ever more marginal lands. By the late 1960s, farmers became extremely vulnerable to droughts.
After independence, international NGOs and donors began to promote simple, low-cost soil and water conservation techniques combined with agroforestry to support local livelihoods. Around the same time, Niger’s government reassessed its governance of rural land and natural resources. New laws and regulations strengthened local rights to benefit from trees, while the Forest Service was transformed from a paramilitary institution that punished farmers for cutting trees into an extension service that helped them adopt simple tree management processes. As a result, farmers began nurturing underground roots and tree stumps in their barren fields. Today, smallholder farmers have revitalized more than 5 million hectares of land. The trees that grow have enriched the soil and provide food, fodder, fuel wood and other goods. Crop yields and incomes have increased too. Moreover, the increased carbon in the trees and in the soil serves to reduce greenhouse gas emissions.
According the Montpellier Panel, a group of European and African experts in the fields of agriculture, ecology and food security, soil is the cornerstone of food security and agricultural development. Its care, restoration, enhancement and conservation should become a major global priority. Along with food, water and energy security, sustainable land management should be a focus area within the post-2015 global development agenda that commits and builds on the Rio+20 target of Zero Net Land Degradation. Donors and governments must therefore commit resources dedicated to sustainable land and soil management practices. Let us hope that as global leaders work over the coming years to implement the SDGs and a new international climate agreement they will remember that soil is not just an ordinary matter, but holds the key to improving agricultural productivity, thereby increasing the resilience of millions of vulnerable smallholder farmers while making significant contributions to co-benefits for mitigation.