Agricultural ammonia emission inventory and characteristics analysis of typical cities in Huanghuai Plain: take Bozhou City as an example

Bozhou City is a typical city in Huanghuai Plain, and agriculture is the largest source of ammonia emission. In order to further understand the agricultural ammonia emission characteristics of typical cities in Huanghuai Plain, based on the activity data and emission factors of six types of agricultural sources including livestock and poultry breeding, nitrogen fertilizer application, nitrogen-fixing plants, soil background, straw compost and human manure, the ammonia emission inventory of agricultural sources in Bozhou City from 2011 to 2018 was established to analyze the emission structure, spatial patterns, historical trends and their uncertainties. The results showed that the total ammonia emissions from agricultural sources in Bozhou City in 2018 were 27 529.19 t/a, of which livestock and poultry breeding and nitrogen fertilizer application were the two major sources of agricultural ammonia emissions, accounting for 68.81% and 16.85%, respectively. The emissions were concentrated in Lixin County and Qiaocheng District, accounting for 28.9% and 27.8% of the total emissions of Bozhou City, respectively. The total agricultural ammonia emissions of Bozhou City rose slightly from 35 097.97 t/a in 2011 to 38 441.13 t/a in 2014; from 2015 to 2017, there was little change; and in 2018, it decreased to 27 529.19 t/a. Among various types of sources, ammonia emissions of straw compost and soil background showed a slight increase from 2011 to 2018, while livestock and poultry breeding, nitrogen fertilizer application, nitrogen-fixing plants, and human manure showed a decreasing trend. In addition, the uncertainty range of Bozhou agricultural ammonia emission inventory from 2011 to 2018 was between -22% and 26%, which was small.