Direct and indirect nitrous oxide emissions from the TERENO field sites
The central aim of this project, conducted in the frame of the Helmholtz portfolio theme Water Science Network for the Future, is to quantify N2O emissions that evolve either directly from fertilizer or atmospheric nitrogen (direct emissions) or indirectly from nitrogen losses via leaching and runoff (indirect emissions). The work comprises field experiments at the three TERENO sites run by the IBG-3 (http://www.tereno.net), i.e. a crop field, a fertilized grassland and a forest site as unfertilized reference equipped with highly instrumented lysimeters, where nitrate and DON leaching is already being monitored. Nitrous oxide emissions will be measured with automated and manual chambers with subsequent N2O analysis in the lab. Additional 15N-labeling experiments will be conducted at selected lysimeters to follow and quantify the loss pathways of nitrogen as a function of environmental parameters (temperature, precipitation, vegetation cover). The work will be complemented by laboratory incubation studies and modeling of matter fluxes and nitrogen dynamics.
Dr. Daniel Weymann