[A 2013-based Atmospheric Ammonia Emission Inventory and Its Characteristic of Spatial Distribution in Henan...

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.