TY - JOUR
T1 - Two options to explain the ammonia gap in The Netherlands
AU - Erisman, Jan Willem
AU - Mosquera, Julio
AU - Hensen, Arjan
PY - 2001/4
Y1 - 2001/4
N2 - This paper addresses two hypothesis that try to explain the difference observed between the estimated NH3 emission levels in The Netherlands and those indicated by atmospheric measurements, the so called 'ammonia gap': the role of SO2 emissions regulating ambient NH3 concentrations through co-deposition, and long-term NH3 emissions after slurry injection. It was found that throughfall measurements of NH4+ could not be used as indicator for changes in NH3 emissions. The throughfall deposition of NH4+ is in close equilibrium to SO42- and NO3- and is thus regulated by the equilibrium of ambient NH3 and NH4+ in wet deposition and canopy water layers. When SO2 emissions decrease, the amount of available SO42- decreases, which imposes a limit on the deposition of (NH4)2SO4. Long-term emissions of NH3 after application of manure were monitored using a new technique, which continuously measures the concentration of NH3 in a cross-section of the emission plume downwind of the source. The emissions could be registered for 3 weeks after application of manure. The results indicate that the long-term emissions only contribute 1-2% to the total emission level. Both the effect of SO2 on the NH3 deposition levels and the long-term emission fluxes are not enough to explain the observed ammonia gap. It seems that several counteracting effects, some of them emerging from the new emission reduction regulations, contribute to the ammonia gap. An integrated approach to abate ammonia emissions is, therefore, needed. The implementation and regulation of production ceilings for reactive nitrogen might be a good option. © 2001 Elsevier Science Ltd.
AB - This paper addresses two hypothesis that try to explain the difference observed between the estimated NH3 emission levels in The Netherlands and those indicated by atmospheric measurements, the so called 'ammonia gap': the role of SO2 emissions regulating ambient NH3 concentrations through co-deposition, and long-term NH3 emissions after slurry injection. It was found that throughfall measurements of NH4+ could not be used as indicator for changes in NH3 emissions. The throughfall deposition of NH4+ is in close equilibrium to SO42- and NO3- and is thus regulated by the equilibrium of ambient NH3 and NH4+ in wet deposition and canopy water layers. When SO2 emissions decrease, the amount of available SO42- decreases, which imposes a limit on the deposition of (NH4)2SO4. Long-term emissions of NH3 after application of manure were monitored using a new technique, which continuously measures the concentration of NH3 in a cross-section of the emission plume downwind of the source. The emissions could be registered for 3 weeks after application of manure. The results indicate that the long-term emissions only contribute 1-2% to the total emission level. Both the effect of SO2 on the NH3 deposition levels and the long-term emission fluxes are not enough to explain the observed ammonia gap. It seems that several counteracting effects, some of them emerging from the new emission reduction regulations, contribute to the ammonia gap. An integrated approach to abate ammonia emissions is, therefore, needed. The implementation and regulation of production ceilings for reactive nitrogen might be a good option. © 2001 Elsevier Science Ltd.
UR - http://www.scopus.com/inward/record.url?scp=0038759964&partnerID=8YFLogxK
U2 - 10.1016/S1462-9011(00)00115-5
DO - 10.1016/S1462-9011(00)00115-5
M3 - Article
SN - 1462-9011
VL - 4
SP - 97
EP - 105
JO - Environmental Science and Policy
JF - Environmental Science and Policy
IS - 2-3
ER -