中国水体硝酸盐氮氧双稳定同位素溯源研究进展  

Review of Dual Stable Isotope Technique for Nitrate Source Identification in Surface-and Groundwater in China

作　　者：徐志伟[1,2] 张心昱[1] 于贵瑞[1] 孙晓敏[1] 温学发[1] 

机构地区：[1]中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室,北京100101 [2]中国科学院大学,北京100049

出　　处：《环境科学》2014年第8期3230-3238,共9页Environmental Science

基　　金：中国科学院知识创新工程重要方向项目(KZCX2-EW-310);国家自然科学基金项目(41171153);中国科学院地理科学与资源研究所自主部署创新项目(201003006)

摘　　要：由于人类活动影响,水体硝酸盐(NO-3)污染已经成为世界范围内的环境问题.结合NO-3中δ15N、δ18O双稳定同位素技术、其他环境同位素以及化学分析技术,可以定量评价地表水、地下水、降水中NO-3不同来源贡献率、硝化/反硝化过程,为水体NO-3污染治理提供了有利依据.本文综述了国内外NO-3中δ15N、δ18O分析测试技术、NO-3污染源δ15N、δ18O特征值、应用δ15N、δ18O进行地表水、地下水溯源研究进展.目前,国内已经成功应用离子交换-AgNO3法和细菌反硝化法开展水体NO-3污染来源的同位素示踪研究.综合分析NO-3污染源中δ15N表明,我国粪肥及污水NO-3的δ15N为3‰～17‰,土壤中NO-3的δ15N为3‰～8‰、大气降水中NO-3的δ15N为-9‰～9‰、化肥中NO-3的δ15N为-2‰～4‰,化肥中NH+4的δ15N为-4‰～2‰.对地表水、地下水中的NO-3溯源研究表明,污水、粪肥已经成为我国水体NO-3污染的重要来源,中国的城市污水、农业水产养殖对地表水水体NO-3污染带来了严重的影响.未来应结合长期监测、δ15N和δ18O双同位素技术和水化学分析技术,提高NO-3不同来源的比例、季节动态定量评价水平,为我国水环境管理提供有效依据.Water nitrate（NO3^-） contamination is a world-wide environmental problem under the effects of intensive human activities.Sources identification of NO3^-contamination in water is important for better management of water quality. Dual stable isotope data of nitrate nitrogen（δ^15） and nitrate oxygen（δ^18） combined with other stable isotopes and chemical analysis data have been frequently used to identify NO3^-sources,differentiate percentage of the different NO3^-sources and assess the nitrification/denitrification processes of surface water,groundwater and precipitation,respectively. This review summarized the analysis technique of nitrate δ^15 and δ^18 in domestic and abroad,assessed typical values of δ^15,δ^18 from different NO3^- sources and evaluated the progress in application of dual stable isotope of δ^15 and δ^18 technique to trace NO3^-sources in surface- and ground-water. Both ion exchange-AgNO3 and bacteria denitrifying methods have been successfully used in tracing water nitrate sources nationwide. The comprehensive metadata analysis of nitrate sources showed that the δ^15 values of sewage and manure,soil,precipitation,fertilizer ranged from 3‰ to 17‰,3‰ to 8‰,- 9‰ to 9‰,- 2‰ to 4‰,respectively. And the δ^15 values of ammonium fertilizer ranged from- 4‰ to 2‰. According to the stable isotope technique,sewage and manure were identified as the major nitrate sources of surface- and ground-water in China This indicated that municipal sewage and aquaculture exerted serious influence on the nitrate pollution of surface water. In the future,longterm monitoring,dual stable isotope fingerprinting and hydro-chemical analysis should be applied together to quantitatively differentiate contribution of nitrate sources,and to assess seasonal dynamic of nitrate sources. It will provide useful scientific basis for water environmental management of China.

关 键 词：硝酸盐氮同位素(δ^15N) 硝酸盐氧同位素(δ^18O) 分析方法 来源 贡献率 反硝化过程 

分 类 号：X52[环境科学与工程—环境工程]