Emissies naar lucht uit de landbouw in 2017 : Berekeningen met het model NEMA

Agricultural activities are in the Netherlands a major source of gaseous emission as ammonia (NH3), nitrogen oxide (NO),nitrous oxide (N2O), methane (CH4) and non-methane volatile organic compounds (NMVOC) and particulate matter (PM10 andPM2.5). The emissions in 2017 were calculated using the National Emission Model for Agriculture (NEMA). The method calculatesthe NH3 emission from livestock manure based on the total ammonia nitrogen (TAN) content in manure. In 2017 NH3 emissionsfrom livestock manure, fertilizer and other sources in agriculture, from hobby farms, private parties and manure application onnature areas amounted to 120.5 million kg NH3, 3.9 million kg more than in 2016. Nitrogen excretion increased due to a largerfeed requirement for dairy cows and higher nitrogen levels in roughage. N2O emissions in 2017 were 21.3 million kg, slightlyabove the level of 2016 (20.7 million kg). The NO emission in 2017 amounted to 23.1 million kg compared to 22.5 million kg in2016. The CH4 emission decreased due to the shrinking of the dairy herd from 508 to 503 million kg. NMVOC emissionsamounted to 98 million kg in 2017 compared to 99 million kg in 2016. Emissions of particulate matter PM10 and PM2.5, 6.2 and0.6 million kg respectively, hardly changed compared to 2016. Some figures in the time series 1990-2016 were revised onbasis of new insights. NH3 emissions from livestock manure in the Netherlands dropped by two thirds since 1990, mainly as aresult of lower nitrogen excretion rates by livestock and low emission manure application. Emissions of N2O and NO alsodecreased over the same period, but less strongly (38% and 31% respectively), due to higher emissions from manure injectioninto the soil and the shift from poultry housing systems with slurry manure towards solid manure systems. CH4 emissions reducedby 14% between 1990 and 2017, caused by a decrease in livestock numbers and increased feed efficiency of dairy cattle.