摘要
为揭示太湖流域降雨和湖水酸根阴离子长期变化特征及环境意义,通过历史数据收集和采样分析,对太湖流域降雨和湖水中的SO_4^(2-)、NO_3^-变化特征和来源进行了研究.结果表明:自1990s以来太湖流域降雨中SO_4^(2-)呈显著下降趋势,年平均下降率为0.28 mg/(L·a); NO_3^-浓度却呈显著上升趋势,年平均增长率为0.05 mg/(L·a),降雨中氮污染呈现加重的趋势.与之相反,湖水中SO_4^(2-)呈显著上升趋势,年平均增长率为1.24 mg/(L·a); NO_3^-浓度却呈显著下降趋势,年平均下降率为0.02 mg/(L·a). 30年以来,太湖水体SO_4^(2-)/NO_3^-比值不断升高,远高于降水SO_4^(2-)/NO_3^-比值.研究认为:流域SO2排放引起的酸沉降是湖水SO_4^(2-)浓度增长的最重要原因,但氮氧化物排放并未引起湖水NO_3^-浓度升高,说明太湖流域对大气沉降的氮氧化物有滞留作用,而太湖水体是流域大气沉降硫酸盐的重要汇.综合治理太湖流域酸性物质排放对防止太湖水体酸化和治理富营养化都具有重要意义.
To explore long-term trends of acid anions in the rain water in Lake Taihu watershed,the lake water and their environmental implications,the variation characteristics,sources and the relationships of SO4^2-,NO3^-in the rain water and the lake water were studied via historical data collection and sampling analysis.The results indicated that SO4^2-in the rainwater showed a significant decreasing trend since 1990s with an annual average decrease rate of 0.28 mg/(L·a),and the NO3^-showed a significant increasing trend with an annual average increase rate of 0.05 mg/(L·a),which suggests an aggravating trend of nitrogen pollution in the rain water.In contrast,SO4^2-in the lake water showed a significant increasing trend with an annual average increase rate of 1.24 mg/(L·a),and the NO3^-showed a significant decreasing trend with an annual average decrease rate of 0.02 mg/(L·a).During the past 30 years,the ratio of SO4^2-/NO3^-in Lake Taihu water continuously increased,much higher than that of the rain water.The research indicated that the acid deposition caused by SO2 emissions in the watershed was mainly responsible for the increased concentration of SO4^2-in the lake water.However,the nitrogen oxides emissions did not cause an increase concentration of NO3^-in the lake water,indicating that Lake Taihu watershed plays a significant role in the retention of nitrogen deposition,while the lake water is an important sink for sulfate deposition.The regional nitrogen deposition has an important impact on Lake Taihu water eutrophication.It is of great significance to prevent the acidification and eutrophication in Lake Taihu via comprehensive management of acid emissions in Lake Taihu watershed.
作者
赵健
代丹
王瑞
郝晨林
何成达
于涛
ZHAO Jian;DAI Dan;WANG Rui;HAO Chenlin;HE Chengda;YU Tao(Chinese Research Academy of Environmental Sciences,Beijing 100012,P.R.China;College of Water Sciences,Beijing Normal University,Beijing 100875,P.R.China;College of Environmental Science and Technology,Yangzhou University,Yangzhou 225217,P.R.China)
出处
《湖泊科学》
EI
CAS
CSCD
北大核心
2019年第1期88-98,共11页
Journal of Lake Sciences
基金
国家水体污染控制与治理科技重大专项(2018ZX07208001
2017ZX07301003)
中国环境科学研究院环境基准与风险评估国家重点实验室基金项目(SKLECRA2016OFP11
SKLECRA2017OFP01)联合资助
关键词
酸根阴离子
酸沉降
富营养化
降雨
太湖
Acid anions
acid deposition
eutrophication
rainwater
Lake Taihu