Spatial and sectorial disaggregation of N2O emissions from agriculture in Belgium.

Abstract

In this study N2O emissions from agriculture in Belgium have been split up per agro-pedological region and calculated per farm type. The N2O emissions were calculated according to the `Revised 1996 IPCC guidelines for national greenhouse gas inventories'. Input data were weighed averages of the N balance of a large number of farms per agro-pedological region and per farm type. As such, the input data represent a theoretical farm in each agro-pedological region and for each distinguished farm type. In a first part, N2O emissions were calculated for 10 agro-pedological regions in Belgium. The yearly N2O emissions varied between 225 and 462 kg N2O-N. The highest N2O emissions (around 400 kg N2O-N yr−1) were found in regions with fertile soils, dominated by crop production or a combination of crop production and cattle breeding. The lowest emissions (around 250 kg N2O-N yr−1) were found in regions with extensive cattle breeding. N2O emissions of 300 ± 15 kg N2O-N yr−1 were found in regions with less extensive cattle breeding or in regions with combinations of cattle, pig and poultry breeding. The N2O emission per ha varied between 6 and 14 kg N2O-N yr−1. In a second part, N2O emissions were calculated for 12 different farm types. The yearly N2O emissions varied between 273 and 512 kg N2O-N. The highest emissions were found on farms with crop production or a combination of crop production and cattle breeding. The lowest emissions were found on farms specialised in only one activity of animal breeding. Specialised pig farms and farms with combinations of cattle caused the greatest threat with respect to N2O releases from agriculture. Their N2O emission per ha was 18–40 kg N2O-N yr−1, which was significantly higher than the average N2O release (10 kg N2O-N yr−1 ha−1) for the other farm types.