[Inventory and Distribution Characteristics of Anthropogenic Ammonia Emissions in Zhejiang Province from 2008 to 2018].

As ammonia is the main component of PM _2.5 , long time series of ammonia emission characteristics are an important basis for studying the historical causes of PM _2.5 pollution. In this study, the activity data of various anthropogenic ammonia emissions from 11 cities were collected in Zhejiang. The anthropogenic ammonia emissions inventory in Zhejiang was established using emission factors, and then a 1 km×1 km spatial grid distribution was carried out using ArcGIS software. The results showed that from 2008 to 2018, the ammonia emissions from anthropogenic sources in Zhejiang exhibited a downward trend, with an average annual decline rate of approximately 3.97%. The ammonia emissions were 108.52 kt in 2018, and the emission intensity was 1.03 t·km ^-2 , in which there was 90.02 kt from agricultural sources and 18.50 kt from non-agricultural sources. The ammonia emissions of Hangzhou, Jiaxing, and Wenzhou were higher than those of the other cities, accounting for 14.72%, 11.86%, and 11.80% of the total ammonia emissions, respectively. The spatial distribution characteristics showed that ammonia emissions were mainly distributed in the northern part of Zhejiang, showing an emission trend of "high in the north and low in the south." Uncertainty analysis showed that the simulated average value of ammonia emissions was 108.37 kt, and the uncertainty range in the 95% confidence interval was -5.40%-5.60%.