西宁市农牧源氨排放清单及其分布特征

Agricultural Ammonia Emission Inventory and Its Distribution in Xining City

以西宁市为研究区域,通过实地调研获得西宁市农牧源活动水平数据,利用排放因子法编制了西宁市2018年农牧源氨排放清单.分析了西宁市农牧源氨排放特征,利用ArcGIS进行3 km×3 km的空间网格化分配,利用蒙特卡罗模拟对畜禽养殖和氮肥施用氨排放清单进行不确定性分析.结果表明,西宁市2018年农牧源氨排放总量为4644.58 t.其中,氮肥施用和畜禽养殖的氨年排放总量分别为1664.84 t和2979.75 t,分别占西宁市农牧源氨排放总量的35.84%和64.16%.空间分布的结果表明,西宁市农牧源氨排放主要来自大通县、湟源县和湟中区,分别占西宁市农牧源氨排放总量的40.10%、30.66%和28.05%.从月份分配来看,畜禽养殖氨排放无月份差异,氮肥施用氨排放集中在6月和7月,排放量分别为799.96 t和768.48 t,分别占全年排放量的48.05%和46.16%.蒙特卡罗模拟结果表明,在95%置信区间下,西宁市农牧源氨排放不确定性较低,为-24.38%~26.71%.

Based on the field research activity level,the emission inventory of agricultural ammonia in Xining City in 2018 was established using the emission factor method.The emission characteristics of agricultural ammonia in Xining City were analyzed,a spatial grid distribution of 3 km×3 km was carried out by ArcGIS,and an uncertainty analysis of the ammonia emission inventory of livestock and poultry breeding and nitrogen fertilizer application was carried out via Monte Carlo simulation.The results showed that the total amount of ammonia emissions from agricultural sources in Xining City in 2018 was 4644.58 t.Among them,the total annual ammonia emissions from nitrogen fertilizer application and livestock and poultry farming were 1664.84 t and 2979.75 t,respectively,accounting for 35.84%and 64.16%of the total ammonia emissions from agricultural sources in Xining City.The spatial distribution results showed that the agricultural source ammonia emissions of Xining City mainly came from Datong County,Huangyuan County,and Huangzhong County,which accounted for 40.10%,30.66%,and 28.05%of the total agricultural source ammonia emissions of Xining City,respectively.From the perspective of monthly distribution,no monthly difference in ammonia emissions was found in livestock and poultry farming.The ammonia emissions from nitrogen fertilizer application mainly existed in June(799.96 t)and July(768.48 t),accounting for 48.05%and 46.16%of the annual emissions.Monte Carlo simulation results showed that under a 95%confidence interval,the uncertainties of ammonia emissions from nitrogen fertilizer application agricultural source ammonia were low,ranging from-24.38%to 26.71%.