Options to reduce greenhouse gas emissions from enteric fermentation and manure handling in dairy farming – An analysis based on farm network data

Summary

In the project ‘Climate effects and Sustainability of Organic and Conventional Farming Systems’ dairy farms in Germany were analysed for their greenhouse gas (GHG) emissions based on the whole process chain (Hülsbergen and Rahmann, 2013). This article focuses on the main GHG from dairy production. The most important source is methane (CH4) from enteric fermentation of the cows. Second important are the GHG from livestock manure: CH4, nitrous oxide (N2O) and indirect N2O-emissions (N2Oindirect) by ammonia (NH3) deposition on soils. They are determined by manure composition, manure management in stables and storage and by excreta of grazing animals dropped on pasture. The results from organic and conventional dairy farms are presented. A view on limits of modelling approaches based on practical farm data is given. Some practical advices for farm management to produce climate friendlier milk are concluded.