The soil beneath our feet holds enormous, yet often overlooked, potential for addressing the climate crisis. In its natural state, soil stores extraordinarily large amounts of carbon. As a result of the intensification of However, with the rapid development of agriculture and ongoing climate change, we face a real risk that this key carbon sink will become another source of dangerous emissions. The concept of the so-called „"carbon farming" aims to prevent this scenario, and the European Union is already gradually creating the necessary legal framework, but experts warn that we still face many scientific, economic and certification challenges.

The Land Paradox: From Repository to Emitter

The importance of maintaining healthy soils has long been absent from the broader political discourse and has only recently received increased attention, particularly in the context of achieving global climate goals. This shift is fully justified. Healthy soils can bind two to four times more carbon than the entire atmosphere and vegetation combined., making them a critical tool for keeping global warming below two degrees Celsius.

But the benefits extend far beyond carbon storage alone. As Alfred Hartemink, a professor of soil science at the University of Wisconsin-Madison, explains: „Soil is at the intersection of all the major environmental challenges, such as climate, biodiversity, food and water security.“ In general, A high proportion of soil organic carbon (SOC) directly correlates with increased soil quality and its better resistance to external stressors.

On the other hand, intensive agricultural practices and climate change are putting enormous pressure on the soil and draining it of stored carbon. Carsten Müller, professor of soil science at TU Berlin, illustrates this historical and current development as follows: „Ever since humans transitioned from hunter-gatherers to settled agriculture and livestock farming, we have been losing carbon from our soils.“ Our agricultural practices and cropping systems caused the initial losses, but the situation is now extremely complicated by anthropogenic climate change. Increasingly frequent catastrophic events such as large-scale forest fires not only nullify the soil’s function as a storage site, but also lead to massive carbon releases. Rising temperatures and prolonged droughts are also accelerating the decomposition of organic matter in the soil, which in the worst case scenario will turn the soil into a net source of CO2 emissions.

The complexity of measuring soil carbon

While measuring atmospheric CO2 concentrations is scientifically relatively straightforward, determining the carbon sequestration capacity of soils is extremely challenging. Soils are spatially very heterogeneous; even small areas can exhibit huge differences in vegetation, structure, and nutrient levels. Therefore, individual samples are rarely fully representative.

Another obstacle is soil management itself. Practices such as tillage, sowing and fertilizing cause constant fluctuations in carbon content. Müller points out that tillage, for example, creates different soil densities – freshly ploughed soil is loose, while later in the year it settles, which changes its volume. Calculating the exact relationship between weight and different soil volumes is very difficult. The data therefore depends on the location, method, and also the time of sampling during the annual cycle. Although existing measurement methods are reliable, they are too laborious and expensive to apply over large areas.

Connecting research with practice: MRV4SOC project

The project addresses this problem MRV4SOC, which is funded by the European Union and aims to create a robust, transparent and cost-effective monitoring, reporting and verification (MRV) system for soil organic carbon. Project coordinator Marta Giménez Gómez explains their innovative approach: „The project aims to design… a Tier 3 approach to capture the dynamics of soil organic carbon storage. This means that we use process models.“.

By combining in-situ (field) measurements with remote sensing data and modeling, scientists can scale up assessments over large areas without having to physically measure every single location. The system is currently being tested in 15 diverse locations – from agricultural and forest land to peatlands, taking into account ecosystem health, climate data and historical land use.

Politics, markets and certification limits

These scientific advances come at a critical time. The EU Regulation on Carbon Removal and Carbon Farming (CRCF) came into force at the end of 2024, creating a voluntary legal framework for the certification of carbon removal and storage. The aim is to incentivise farmers to manage their land sustainably through tradable carbon credits.

However, experts warn of the limits of this „soil solution.“ A fundamental obstacle is the permanence of the carbon stored in this way. Marta Giménez Gómez points out that „Weather extremes and long-term climate change… may cause a reversal of the positive effects achieved through carbon farming practices“. Moreover, the storage capacity of soil is finite and other greenhouse gases, such as nitrous oxide (N2O), which has a much higher global warming potential than CO2, must also be taken into account.

From an economic perspective, farmers face high volatility in carbon price, significant monitoring costs and excessive bureaucracy. Paradoxically, a system that rewards additional carbon storage also risks financially disadvantageing farmers who have been implementing sustainable practices for years. The success of the system also depends on farmers’ willingness to overcome the technical complexity of the procedures and market uncertainty.

Protection against greenwashing and a holistic approach

A key aspect of certification is protection against greenwashing. If corporations are using credits to offset their emissions instead of actually reducing them, there needs to be bulletproof data. „"Extraordinary claims require extraordinary evidence,"“ Hartemink emphasizes the need for verifiable and transparent soil models.

Ultimately, focusing solely on the amount of carbon stored is too narrow. Professor Müller points out that what is far more crucial is the overall function of soil carbon for fertility, water retention and climate. Carbon is only one component of total organic matter, and efforts to increase it directly support other critical functions, including biodiversity. A sustainable approach must therefore harmoniously integrate economic incentives and certification with overall soil health, which should become an absolute pillar of our fight against climate change. JRi&CO2AI