Atmospheric nitrogen deposition in Yangtze River Delta:insights gained from the nitrogen content and isotopic composition of the moss Haplocladium microphyllum  

石生苔藓能指示长三角大气氮湿沉降量及其来源吗?

作　　者：CHEN Zhili HUANG Tao FAN Rong YANG Hao YANG Yanju HUANG Changchun 

机构地区：[1]School of Geography Science,Nanjing Normal University,Nanjing,China [2]Institute of Surface-Earth System Science,Tianjin University,Tianjin,China [3]Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application,Nanjing Normal University,Nanjing,China [4]Ministry of Education,Key Laboratory of Virtual Geographic Environment,Nanjing,China [5]State Key Laboratory Cultivation Base of Geographical Environment Evolution,Nanjing,China [6]College of Environmental Science and Engineering,Yangzhou University,Yangzhou,China

出　　处：《Atmospheric and Oceanic Science Letters》2020年第3期202-209,共8页大气和海洋科学快报（英文版）

基　　金：This study was funded by the National Natural Science Foundation of China[grant numbers 41571324,41673108,41701329,and 41771380];the National Program on Key Basic Research Project(973 Program)[grant number 2014CB953800];the Natural Science Foundation of the Jiangsu Higher Education Institutions of China[grant number 16KJD170001];the Natural Science Foundation of Hainan Province,China[grant number 317190];the CAGS Research Fund[grant numbers YYWF201637,201724].

摘　　要：Simple and inexpensive estimation of the rates and sources of atmospheric nitrogen(N)deposition is critical for its effective mitigation in a region with different land-use types.In this study,the N content and N isotopic composition(δ15N)of moss(Haplocladium microphyllum)tissues and precipitation at six sites with three land-use types(urban,suburban,and rural)were measured in the Yangtze River Delta.A significant linear relationship between moss N content and wet N deposition,and a consistent decrease trend for moss N content and wet N deposition from urban to suburban to rural areas were observed.More negativeδ15N of suburban and rural mosses indicated N mainly released from agriculture and effluent,while the less negativeδ15N of urban mosses were mainly influenced by fossil fuel combustion and traffic emissions.Although the negative mossδ15N indicates that reduced N dominates wet N deposition,there was no significant correlation between mossδ15N and the ratio of ammonium to nitrate(NH4+/NO3−).These results reveal that the moss N content andδ15N can be used as a complementary tool for estimating the rates and sources of wet N deposition in a region with different land-use types.简单有效地估算大气氮沉降量及其来源至关重要。本研究同时收集长三角市区,郊区,农村的雨水和附近的石生细叶小羽藓,分析苔藓氮含量与氮湿沉降量以及苔藓和雨水的氮同位素(δ15N)。结果显示:苔藓氮含量与氮湿沉降量显著相关,均呈市区>郊区>农村趋势。苔藓δ15N表明郊区和农村大气氮湿沉降主要来自农业和人畜废水释放,而市区还受煤炭燃烧和机动车排放影响。该研究表明石生苔藓氮含量和δ15N能用来指示长三角大气氮湿沉降量及其来源,以弥补传统氮沉降监测数据的缺乏和费时费力的缺点。

关 键 词：Epilithic mosses nitrogen content nitrogen isotope atmospheric wet nitrogen deposition sources 

分 类 号：X51[环境科学与工程—环境工程]