菏泽市农业源氨排放特征研究

Study on characteristics of agricultural ammonia emission in Heze City

农业源是空气中氨的主要来源,对空气质量有着重要影响,开展农业源氨排放特征研究可以为制定氨减排策略、消除其对生态环境的潜在风险、改善空气质量提供科学依据。在收集菏泽市五类主要农业源氨排放活动水平数据的基础上,采用排放因子法计算了该地区2016—2020年农业源氨排放量,分析了其排放特征及与PM_(2.5)的关系,并按趋势照常模式预测了菏泽市2025年氨排放量。结果表明,十三五期间菏泽市农业源氨排放量呈逐年下降趋势,但均大于10万t·a^(-1),2020年排放量最低,为11.82万t·a^(-1),较2016年下降28.9%。畜禽养殖源和氮肥源对氨排放量贡献最大,两者的氨排放量占农业源氨排放量的90%以上。相关性分析表明,农业源氨排放强度与空气PM_(2.5)浓度呈正相关关系,相关系数达到0.793,说明农业源氨排放强度是PM_(2.5)浓度重要影响因素之一。在趋势照常模式下,2025年菏泽市农业源氨排放量预测为13.76万t·a^(-1),明显高于2020年水平,建议尽快采取农业源氨排放控制措施以防止空气质量恶化。

Ammonia in atmosphere mainly originates from agricultural activities and has an important effect on air quality.Study on characteristics of agricultural ammonia emissions can provide a scientific basis for formulating ammonia emission reduction strategies,eliminating the potential risk to ecosystem and improving air quality.Based on activity data of five agricultural ammonia emission sources from 2016 to 2020 in Heze city,the amounts of ammonia emission was estimated by use of emission factor method,the ammonia emission characteristics and the correlation between ammonia emission intensity and PM_(2.5) concentration were analyzed.The amount of ammonia emission in 2025 was predicted under business-as-usual scenario.The result showed that the amounts of agricultural ammonia emission in Heze from 2016 to 2020 were higher than 100,000 t·a^(-1),and showed a trend of decreasing year by year.The lowest ammonia emission was 118,200 t·a^(-1) in 2020,with a decrease of 28.9%than that in 2016.Livestock breeding and nitrogen fertilizer were identified as the main ammonia emission sources,which contributed more than 90%of total ammonia emission.Correlation analysis showed ammonia emission intensity had a positive correlation with PM_(2.5) concentration and the correlation coefficient was 0.793 which proved ammonia emission intensity was one of important factors of influencing PM_(2.5) concentration.Under business-as-usual scenario,the amount of agricultural ammonia emission was estimated as 137,600 t·a^(-1),and significantly higher than that in 2020.So control measures of agricultural ammonia emission were advised to taken as soon as possible to prevent deterioration of air quality.