Research Project TRUESOIL – 2022 to 2025
True SOC sequestration: understanding trade-offs and dynamic interactions between SOC stocks and GHG emissions for climate-smart agrisoil management
Carbon sequestration in soils is an effective way to remove carbon dioxide (CO2) from the atmosphere and mitigate climate change. In addition, increased soil organic matter is associated with multiple benefits for ecosystem functioning including crop productivity and food securing, water retention and flood/erosion control, nutrient cycling and pollution and soil biodiversity.Agricultural soils are globally depleted in soil organic carbon (OC) and therefore, they exhibit a high potential for carbon sequestration under appropriate management practices. Several agroecological management practices aim to increase or retain soil OC through increased carbon inputs (e.g. organic amendments and plant litter), alternative cropping systems (e.g. continuous cover crop) and/or measures to reduce soil OC losses (e.g. reduced or no tillage and adaptive grazing). However, the same practices might increase greenhouse gas (GHG) emissions such as CO2, nitrous oxide (N2O) and methane (CH4), restricting their effectiveness to mitigate climate change. To date, we still lack an understanding on the mechanisms and drivers behind increased GHG emissions and their interactions with OC sequestration under different soil and climatic conditions, partly because little is known about how abiotic and biotic factors control the extent to which soils can store OC. Quantifying negative side-effects of increased soil OC sequestration on GHG emissions is necessary to develop appropriate management options that reduce GHGs while increasing soil OC stocks.
In agricultural soils, the interactions and trade-offs between agroecological practices, carbon sequestration and GHGs emissions are controlled by various biotic and abiotic factors, including vegetation and soil properties and climatic conditions. This leads to a mosaic of potential systems and outcomes which restricts the development of appropriate management guidelines that reduce GHGs while increasing OC stocks. To tackle this, we need large-scale studies that simultaneously quantify soil carbon sequestration and GHG emissions under distinct environmental conditions while accounting for a large number of parameters in the plant, soil and microbial system.
TRUESOIL’s main goal is to assess how agricultural management influences soil carbon sequestration and GHG emissions from agroecosystems with distinct vegetation, soil properties and climates. Under field conditions, we will elucidate the role of different abiotic and biotic factors in OC storage and the extent to which these factors impact on GHG emissions, in particular N2O, given its high warming potential and large uncertainty in flux estimates. Many carbon-sequestering management interventions are known, or have the potential, to modify soil N cycling leading to enhanced N2O emissions.
Within the TRUESOIL project, scientists from 13 universities and research institutes from around the globe will bring their expertise and collaborate to improve our understanding on trade-offs between soil organic carbon stocks and GHG emissions for climate-smart agricultural soil management. The project will form a network of field experiments that are managed according to local practices, where trade-offs between C sequestration and GHG emissions will be studied under ambient and reduced rainfall. Additional laboratory incubations will be performed to answer deeper scientific questions on the soil-microbial system. Using the unique data acquired, TRUESOIL will use the Denitrification Decomposition model to investigate carbon and nitrogen cycling under future climate scenarios. Because of the large span in terms of pedoclimatic and geographic conditions studied in the project, TRUESOIL will deliver recommendations about management practices that are relevant for practitioners in the partner countries and will provide scientific support for policy development at the European and global levels.
| Partner | University | Country |
| Dr. Ana Meijide | University of Göttingen | Germany |
| University of Helsinki | Finland | |
| National Research Institute for Agriculture | France | |
| University College Dublin | Ireland | |
| University of Chile | Chile | |
| Instituto Nacional de Tecnología | Argentina | |
| Universidad de Granada | Spain | |
| Norwegian University of Life Sciences | Norway | |
| University of Aveiro | Portugal | |
| University of Otago | New Zealand | |
| Université Catholique de Louvain | Belgium | |
| Jimma University Ethiopia | Ethiopia | |
| Universitas Negeri Makassari | Indonesia | |
