RESUMO
Based on the best available activity data at a city level from top down and bottom up methods, a 2013-based emission inventory of NH3 was established for the Henan Province using an emission factors method. The 3 km×3 km spatial gridded distribution was carried out by using GIS technology. The results showed that the total amount of atmospheric NH3 emission in Henan Province in 2013 was 1035.3 kt, and the average emission intensity reached levels of 6.4 t/km2. Livestock and nitrogen fertilizer applications were the top two emission sources, accounting for 52.71% and 31.53% of the total emissions, respectively. Beef, laying hen, and goats were the main contributors in the livestock category, accounting for 34.98%, 16.63%, and 14.02% of the total emissions, respectively. There were different characteristics between emission source contributions and emission intensities in each city. Nanyang, Zhoukou, Shangqiu, and Zhumadian were the prefecture-level cities with large emissions, accounting for 11.53%, 9.84%, 9.62%, and 9.57% of the total amount in Henan Province, respectively. The NH3 emission intensities of Puyang and Louhe were larger than those of other cities, reaching up to 10.7 t·km-2 and 10.2 t·km-2, respectively. The spatial distribution revealed that emissions in the middle eastern region were relatively higher; whereas, the western region emissions were relatively low. The areas with high emissions were concentrated in the plains and densely populated areas.