Mitigation measures of crop cultivation to reduce climate-impacting emissions from denitrification

The joint project 'Measures to reduce direct and indirect climate-impacting emissions caused by denitrification in agricultural soils - MinDen' addresses the topics of reducing nitrous oxide emissions and improving nitrogen efficiency through modeling, the evaluation of possible mitigation measures and the evaluation of denitrification on spatial scale. Gaseous emissions from denitrification cause N losses relevant to crop cultivation and cause direct N2O emissions from crop cultivation. Climate protection measures in crop production in the areas of fertilization, soil cultivation and crop rotation have hardly been researched with regard to the role of denitrification. Crop management that optimizes N efficiency and minimizes N emissions at the same time has therefore not yet been reliably defined. The overall objective of the present project is to identify practicable crop management measures to minimize N2 and N2O emissions from denitrification for arable cropping systems in Germany by improving the knowledge on denitrification-related N losses through field and laboratory studies and using it for parameterization, validation and application of simulation models. Our objectives are as follows: Regionalization of N losses due to denitrification in Germany based on existing models Determination of the effect of crop protection measures on N2 and N2O losses on field scale Testing of mitigation options on the model, laboratory and field scale, taking into account the topsoil and subsoil for different soils Further development of denitrification models to improve the mapping of mitigation measures using existing and new field data Testing of mitigation options for Germany using the improved models, taking into account yield, economic efficiency, technology requirements, N2O emissions, N efficiency, fertilizer requirements, NH3 emissions and nitrate leaching. We provide an overview of the approach and the current status of the joint project, which started at the beginning of 2023.