SmartMaN2agement

Ammonia (NH3) and nitrous oxide (N2O) are the most important gaseous nitrogen losses in agriculture, along with molecular nitrogen (N2). Leached nitrate (NO3) may induce groundwater contamination and/or surface water eutrophication. Intensively managed croplands are the most important source of leached nitrate. Denitrification is source of N losses in agriculture. It consists of the formation of N2O, a greenhouse gas which has a global warming potential 298 times higher than CO2. Most of the N2O emissions take place in soils and are related with agricultural activities. The focus of the presented project is on the reduction of N2O and NH3 emissions as well as N leaching through predictable, informed and site-adapted management in crop production. The overall aim of the project is to quantify the N losses in multiple sites in Germany and to assess the effects of agricultural management strategies (crop rotation, cover crops, fertilization) on the loss by combining field experiments and process based models. The objectives of the presented project are 1) to better understand the C/N cycle and the factors influencing the losses using a modeling approach 2) generation of a large data set from multiple sites to calibrate and validate the model, 3) to simulate management scenarios (crop rotations, cover crops, organic and inorganic fertilization) and their effects on N losses in order to quantify the effectiveness of mitigation measures in a site-specific manner and under various weather conditions, and 4) To demonstrate the effect of different soil management strategies on the reduction of the Nitrous gas emission and to enable model-based recommendations for climate-friendly nitrogen management. In the model-based approach presented, the SIMPLACE model platform is used to create process-based simulation models that simulate daily nutrient turnover in the soil, nitrate input into groundwater, N2O emissions as a function of soil properties, and plant growth and N uptake. The regionalization is based on existing soil characteristics from the Thünen Institute's German soil inventory and extrapolated weather data. The results allow quantification of nitrogen emissions and the effect of ammonia and nitrous oxide mitigation measures as well as the effects of various measures on nitrogen efficiency and yield.

Dr. Sabine Seidel

Sofia Hadir

Prof. Dr. Nicolas Brüggemann, Forschungszentrum Jülich IBG-3
Dr. Norman Gentsch, Leibniz Universität Hannover
Prof.Dr. Miriam Athmann, Universität Kassel
Prof. Dr. Timo Kautz, Humboldt-Universität zu Berlin