Why is the content of this map important?
SOC plays a vital role in landscapes, affecting soil fertility, many ecosystem services and carbon budgets. Studies on carbon budget indicate that European cropland is currently balanced, with net fluxes ranging from small carbon sources to small sinks. However, global warming is expected to accelerate the SOC decomposition and thus increase carbon emissions from agricultural land.
Which sectors are affected by this result?
Soil organic carbon is the foundation of healthy soil and an asset for food production. It is expected that rising temperatures will lead to thinning of SOC in agricultural land and will negatively impact the soil production function. This may have a negative effect on all cropland-based sectors.
What is shown on the maps?
The simulations with the EURO-CORDEX climate change scenarios indicate a decline in SOC for most of Europe, particularly for northern and south-eastern regions, with a decline by more than 15% compared to the reference period. Higher crop residue and manure inputs may lessen the overall decreasing trend in Western Europe. The projected values of temperature in cold northern climates are increasing, which is going to increase the SOC decomposition and thus reduce the SOC stocks on arable land significantly. The simulations indicate that the losses in SOC under conventional management can be offset by conservative residue and tillage management*) in many regions. Conservative management also reduces soil erosion by more than 20% in most European regions, thus contributing to carbon protection and mitigating climate change.
Details and further information:
*) Conservative residue and tillage management (e.g. reduced tillage and no-till) implies managing the amount and distribution of crop residues on the soil surface year round while minimizing the soil-disturbing operations. It is commonly used to protect soil quality and SOC stock, control soil erosion, and reduce energy use. The methods are also known as mulch tillage or conservation tillage.
The EPIC model was used to simulate soil organic carbon in the upper 0-30 cm. It was driven by the ensemble of the five mandatory climate simulations. Hence, the ensemble consists of 5 simulations in total.
Juraj Balkovic
International Institute for Applied Systems Analysis (IIASA), Austria