Emission factors for methane and nitrous oxide from manure management and mitigation options

Under the United Nations Framework Convention on Climate Change (UNFCCC), the Kyoto-protocol is aimed at reducing the emission of greenhouse gases. Therefore, members report their greenhouse gas (GHG) emissions every year in a National Inventory Report (NIR). For agriculture the Netherlands identify three sources of GHG: enteric fermentation (methane), manure management (methane and nitrous oxide) and agricultural soils (nitrous oxide). The Dutch NIR reported that in 2009 23% of the agricultural GHG was caused by manure management. The methane-emission factors for manure management were assessed by a Tier 2 approach, the nitrous-oxide-emission factors were IPCC 2000-defaults. Between 2008 and 2010 an extensive measuring programme was carried out resulting in emission factors for housing systems of methane and nitrous oxide. Overall it appeared that emission factors of methane were higher than reported in the NIR, and emission factors of nitrous oxide were lower. This study investigates the consequence of those emission factors for the total emission of GHG from livestock housing and manure storage and the perspective of implementation of mitigation measures.