Main research question
Which trade-offs and synergies of soil management options appear in representative European pedo-climatic conditions when we wish to increase soil carbon storage? That is the main question of SOMMIT, an internal research project of the European Joint Programme EJP SOIL. More specifically we want to assess the nature (quality), and the dose of the applied organic matter inputs, how (application method), when and where (pedo-climatic conditions) organic matter is applied and the impact on soil carbon sequestration and the trade-offs including soil N2O and CH4 fluxes and N leaching. We will propose indicators for evaluating the impact of soil management strategies performance in major farming systems across pedo-climatic regions in Europe, while ensuring effective stakeholder involvement.
The SOMMIT approach is bigger than the curren research focus often found regarding carbon sequestration: while we may have a good understanding of the effect of specific soil management strategies on either carbon sequestration or non-CO2 GHG fluxes, integrated investigations are still scarce, with only a few studies addressing trade-offs comprehensively. Therefore, with an integrated and interdisciplinary approach we will address the main pedo-climatic conditions and farming systems in Europe, through 1) synthesis and meta-analysis of available literature and data; 2) novel measurements on key long-term experiments; and 3) simulation of long-term agro-ecological system responses to contrasting management options. Moreover, obtained data will be synthesized through a fuzzy-expert system which will allow for 4) evidence-based identification of optimal strategies for mitigation of trade-offs, and 5) effective stakeholder involvement. SOMMIT uses this procedure for the most common European agricultural systems in various European pedo-climatological zones.
Within the context of climate change there is increasing focus on agricultural practices which contribute to soil carbon sequestration to mitigate rising atmospheric CO2 levels. While it is known that these soil management strategies can also affect soil N2O and CH4 fluxes and N losses through leaching, data and knowledge are still fragmented. With SOMMIT we expect to provide scientific support for a Europe-wide policy approach to the resulting trade-offs given the high global warming potential of N2O. Mitigation effects of agricultural practices enhancing carbon sequestration can largely be offset if N2O emissions increase. Contrastingly, soil management strategies enhancing carbon sequestration and reducing non-CO2 greenhouse gas emissions might imply a “double-win” situation, resulting in effective synergetic mitigation of climate change.