丹江口水库淅川库区大气氨氮干沉降特征及源解析  

Analysis of characteristics and sources of dry atmospheric ammonia nitrogen deposition in the Xichuan area of Danjiangkou reservoir

作　　者：肖春艳[1] 陈飞宏 陈晓舒 赵同谦[1] 郭晓明[1] 胡情情 XIAO Chunyan;CHEN Feihong;CHEN Xiaoshu;ZHAO Tongqian;GUO Xiaoming;HU Qingqing(Department of Resources and Environment,Henan Polytechnic University,Jiaozuo,454003,China)

机构地区：[1]河南理工大学资源环境学院,焦作454003

出　　处：《环境化学》2023年第6期1856-1866,共11页Environmental Chemistry

基　　金：国家自然科学基金(U1704241,42007175);中原科技创新领军人才项目(194200510010);高等学校基本科研业务费(NSFRF200326)资助.

摘　　要：为了解丹江口水库淅川库区大气干沉降中氨氮的沉降特征和主要来源,于2019年9月—2020年8月对库区周边设置的5个大气监测点进行干沉降样品采集,测定并分析了样品中氨氮浓度及其氮同位素,基于贝叶斯混合模型量化了氨氮的主要来源.结果表明,库区大气干沉降中氨氮月均浓度为0.96 mg·L^(-1),全年大气干沉降中氨氮沉降通量为11.77 kg·hm^(-2),δ^(15)N-NH_(4)^(+)值月均值为-9.20‰.干沉降中氨氮沉降通量、浓度和δ^(15)N-NH_(4)^(+)值的季节差异显著,均表现出夏季最高、春季和秋季次之、冬季最低的变化规律,主要与夏季高温和氮肥施用有关.运用稳定同位素模型(SIAR)分析发现,库区干沉降中氨氮的主要污染源为农业源,贡献率为60%,其中化肥释放源和畜禽排放源贡献率分别为36%和24%.夏季农业源贡献率最高,其中64%来源于化肥释放,进一步证实了夏季高温以及氮肥的大量施用是影响库区干沉降中氨氮的主要因素.研究结果为探索库区水体氮污染控制途径提供理论基础和数据支撑.In order to know the characteristics and sources of dry atmospheric ammonia nitrogen deposition in the Xichuan area of Danjiangkou reservoir,the dry deposition samples were collected at the five atmospheric deposition monitoring sites around the reservoir from September 2019 to August 2020.The concentrations andδ^(15)N values of ammonia nitrogen were determined,and the fractional contributions of potential ammonia nitrogen sources were quantitatively calculated using a Bayesian mixing model.The results showed that the monthly averaged concentration of ammonia nitrogen was 0.96 mg·L^(-1),the annual flux of ammonia nitrogen dry deposition was 11.77 kg·hm^(-2),and the monthly averaged value ofδ^(15)N-NH_(4)^(+)was-9.20‰in the dry deposition samples.Significant seasonal differences in the fluxes of ammonia nitrogen dry deposition,concentrations andδ^(15)N values of ammonia nitrogen were found,showing the following order:summer>spring>autumn>winter,which was mainly due to the application of chemical nitrogen fertilizers and high temperature in summer.The fractional contributions of chemical nitrogen fertilizer and livestock wastes were 36%and 24%,respectively,indicating that agricultural release contributed most.In summer,the fractional contribution of agricultural release was the largest,accounting for 64%,which further confirmed that ammonia nitrogen in dry atmospheric deposition primarily was controlled by high temperatures in summer and massive application of chemical nitrogen fertilizers.The results of this study may provide the theoretical and data support in controlling nitrogen pollution into the reservoir.

关 键 词：氨氮 干沉降 氮同位素 源解析 丹江口水库 

分 类 号：X51[环境科学与工程—环境工程]