Agricultural Ammonia Emission Inventory and Characteristics in Yancheng City from 2013 to 2021
Ammonia is an important precursor for secondary generation of PM2.5,which is widely present in the atmospheric environment.Agricultural activities are the main sources of ammonia emissions;thus,establishing a city-scale and county-level agricultural ammonia emission inventory has great significance for improving the accuracy of air quality models and fine-tuning emission reduction measures.Using field investigations and statistical data,a comprehensive ammonia emission inventory of agricultural sources from 2013 to 2021 in Yancheng was established based on the emission factor method.Furthermore,the annual variation,distribution characteristics,and reduction contribution of ammonia emissions from all sources were analyzed.The spatial allocation method for livestock and poultry was improved by integrating detailed activity level data,such as the registration information of industrial and commercial enterprises,as well as land-use datasets.This study showed that 1)the total ammonia emissions from agricultural sources were 87.58 kt in 2021,with nitrogen fertilizer application and livestock and poultry accounting for 63.1%and 31.6%,respectively.In addition,urea and poultry were the dominant emission sources,with proportions of 86.2%and 69.8%,respectively.2)From 2013 to 2021,the total agricultural ammonia emissions in Yancheng decreased by an annual average rate of 2.8%,which was consistent and slightly higher than the average for Jiangsu Province(where Yancheng is located).The emission intensity per unit area decreased 24.1%from 6.52 t·km-2 to 4.94 t·km-2.Compared with typical cities in key provinces,the agricultural ammonia emission intensity in Yancheng was at an average level but was relatively higher than that in cities in the Yangtze River Delta region.3)Substantial regional differences in agricultural ammonia emissions exist between districts and counties.Dongtai,Dafeng,Sheyang,Binhai,and Funing contributed 75.2%of the total emissions from Yancheng.The emission intensities of Funing,Jianhu,Dongtai,and Binhai were higher than citywide averages.4)From the perspective of emission reduction,among all types of ammonia emission sources,livestock,poultry,and nitrogen fertilizer application had the highest cumulative emission reduction contributions(69.0%and 31.6%,respectively).Since 2016,ammonia emissions from livestock and poultry have decreased by more than 6.0%over five consecutive years.To a certain extent,this was an important reason for the trend in total ammonia emissions from agricultural sources in Yancheng,turning from constant to downward.Future studies should focus on Dongtai,Binhai,and Funing.Ammonia emission control should focus on poultry,urea,and other high-emission sources,as well as fecal storage and treatment,breeding enclosures,and other key agricultural practices.
ammonia emissionemission inventoryagricultural sourcenitrogen fertilizerlivestock and poultryemission reductioncity-scale
万方数据
维普
