Source: French to English Tester Published on: 2026-05-12
Source: The Conversation – in French– By Céline Granjou, research director, Inrae
Long considered solely in terms of their fertility, soils are now being rediscovered for their role as carbon sinks. In other words, their ability to sequester carbon makes them key contributors to the fight against climate change. A sociological study conducted with scientists, politicians, and local public actors highlights this climatic redefinition of soils and its concrete consequences.
While the climatic role of forests as carbon sinks has been known since the 1990s, that of soils is less so. Yet, soils contain three times more carbon and play a key rolein its overall cycle. At the COP21 in Paris in 2015, the French government launched the initiative4 per 1000in order to encourage female and male farmersTo sequester carbon in soils.
By increasing thesoil carbon stocks, the approach aimed to offset fossil emissions whileimproving soil quality. But the capacity of soils to sequester carbon requiresthe adoption of specific agricultural practicesÂ: implementation of plant cover crops, reduction of tillage, planting of hedges or trees, as well as the return to the soil of crop residues such as straw. The preservation of wetlands, forests, and meadows, whose soils are particularly rich in carbon, also helps to mitigate climate change.
How do these various carbon sequestration practices alter soil designs? The team fromANR Posca projectconducted a large sociological survey to answer this question. In the end, more than 250 in-depth interviews with scientists, public decision-makers, local government officials, and agricultural stakeholders.
This survey shows that the rise of sequestration practicesis accompanied by a climatic redefinition of soils. Long considered primarily from the perspective of agricultural fertility, soils are now also seen as carbon sinks. And this, across a wide range of social worlds: scientific research, but also national agricultural policies and territories.
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Trapping carbon in the soil: what agriculture can do
Research to consider soils in light of the climate
Scientists have been working on soil carbon for several decades, often understood in terms of organic matter or humus. This carbonis indeed essential in soil fertility. But since the early 1990s, part of their research has now focused on the description and modelingthe role that soil carbon plays in climate change.
The researchers notably adapted their research questions to investigate the processes that allow for the stabilization of carbon in soils. This made it possible to develop models representing these mechanisms, with the goal of contributing to the improvement of climate scenarios. They also created new monitoring infrastructures for carbon stocks in soils at the national scale, andnew collaborations established with climate sciences.
Climate issues have also led soil scientists to produce new expert studies, both within the framework of the Intergovernmental Panel on Climate Change (IPCC) at the international level, and also at the national level, to estimate the potential for carbon storage in soils. These shifts in their work provide support elements for public policies and economic developments related to carbon sequestration.
Researchers have thus transformed their research agendas and practices to produce knowledge that they consider useful in the fight against climate change. But this has not been without creating new tensions within this discipline, notably around the question ofthe non-permanence of carbon in soils.
Carbon credits for agricultural soils that store
New climatic conceptions of soils are also conveyed by the 4 per 1000 initiative, since its publication at the end of 2015 by the Ministry of Agriculture. This initiative takes its name from the calculation that increasing the overall stock of carbon contained in soils by about 0.4% every year would make it possible to compensatethe annual increase in greenhouse gas emissions.
More recently, a study coordinated by Inrae made it possible tospecify the sequestration potential of national soils. This accounts for about 40% of greenhouse gas emissions from the agricultural sector in France – that is, 6.5% of total national emissions. Admittedly, this is far from compensating for all national greenhouse gas emissions, but it remains a welcome contribution to the mitigation effort that the government wishes to encourage.
This promise of sequestration is all the more emphasized today as it allows the agricultural sector to be repositioned as a solution to climate change, at a time when it is heavily criticized – even though the sector remains a net emitter of greenhouse gases.
The French government has thus launched itslow carbon label(LBC) end of 2018. Certification framework for emission reductions and sequestration practices, it aims, among other things, to reward the efforts of farmers who adopt new virtuous practices. It notably allows certifying the number of tons of sequestered carbon, so that farmers can sell the corresponding carbon credits to companies or local authorities. The principle is that of the carbon market: these buyers will, in turn, be able to claimto a contribution to the effort to mitigate climate change.
The low carbon label helps promote a vision of agricultural soils as carbon sinks that can be optimized through changes in farming practices. However, its impact remains currently limited, because the projects under itultimately mobilize very little carbon sequestration, but rather emission reduction practices.
Communities that quantify the carbon in their soils
Since 2016, new legislation also requires municipalities with more than 20,000 inhabitants to assess the carbon sequestration potential of forests and soils. They must thus design aterritorial air energy climate plan(PCAET) which measures, among other things, the amount of carbon contained in soils and details possible strategies to increase these stocks. However, the regulation remains silent on the means and tools useful for quantifying and managing soil carbon stocks.
In this context, local authorities use various tools to quantify soil carbon. Since soil analyses are lengthy and costly to carry out, these tools generally rely on data and numerical models that predict the evolution of carbon stocks based on different management scenarios.
Ademe has, for example, developed the toolAldo, which allows local government officials and consulting firms to easily obtaincarbon stock values.
Agro-Transfert, an agricultural research and development organization, also created the toolSimeos-AMG. Originally intended to help farmers maintain fertile soils rich in organic matter, it is now used by agricultural professionals to understand the carbon impact of their practices, as well as by certain local administrations to design their territorial climate-air-energy plan. Soil carbon thus becomes a new subject of public action in the territories.
Towards a climatic redefinition of soils
Our research thus highlighted how soils are being redefined in light of climate issues, whether in the worlds of scientific research, national agricultural policies, or local territories. Our results show that this climate-related transformation of soils is now concretely reflected through new practices, commitments, and unprecedented instruments that are developing.
Soils are not moreover reduced to the role of simple carbon reservoirs to be optimized. The survey reveals that many actors, particularly scientists, remind that this carbon to be sequestered can be released back into the atmosphere, especially if the agricultural sequestration practices are notmaintained in the long term.
As a result, it is crucial to embed these changes in the long term. This is all the more important given that these practices are also aligned with gains in soil fertility and quality, the main concerns they had addressed until now. The climatic redefinition of soils thus connects climate mitigation issues with the concerns of maintaining agricultural fertility and conserving soil quality.
Céline Granjou received funding from the National Research Agency for the project ANR-20-CE26-0016
Antoine Doré received funding from the National Research Agency.
Hélène Guillemot received funding from the ANR for the POSCA project.
Laure Manach received funding from the National Research Agency and the TTI.5 Foundation.
Léo Magnin received funding from the National Research Agency (ANR) as part of the POSCA project.
Robin Leclerc received funding from the ANR
Stéphanie Barral received funding from the National Research Agency.
–ref. How have soils become a climate issue? The perspective of sociology –https://theconversation.com/how-soils-have-become-a-climate-issue-the-sociological-perspective-281474