Joint research project "Regional Greenhouse Gas Fluxes in Systems with Grass-Clover and Wheat Crop Sequence"
Organic farming integrates clover and grass mixtures into crop sequences to increase soil fertility. The symbiotic N fixation provides N fertilisation to subsequent crops.
There is a lack of data regarding the impact grass-clover cropping on nitrous oxide (N2O) emission from crop ssequences. The project aimed to derive N2O emission factors for grass-clover and wheat crop sequences. Emission factors are used to estimate N2O emission in dependence on nitrogen input.
Specific project aims were measurement and modelling of N2O fluxes in the central part of the organic farming crop sequences: grass-clover, incorporation of grass-clover and the following wheat in comparison to conventional cropping of winter wheat. Farm specific methods of grass-clover incorporation were investigated and compared regarding their effect on crop yield an potential for mitigation of N2O emission.
The project is geared towards agricultural praxis and consulting. Results will improve the German emission inventories and the Thünen institute's consulting of policy makers.
4 field trials were established in different regions of Germany, comprising rotations with grass-clover followed by wheat in different treatments. Fluxes of nitrous oxide and several soil and environmental parameters were measured for two years.
see the publications for results
10.2010 - 5.2013
Project status: finished