西藏雅鲁藏布江流域生态系统重金属迁移及风险评估

西藏具有高海拔、高寒等独特的自然环境，关于该区域生态系统中重金属的迁移富集的研究甚少。随着经济的发展，藏区目前矿业企业发展迅速，近年来，采矿及冶炼企业所导致的重金属污染引起了公众的关注。西藏雅鲁藏布江流域（一江四河）是中国16大成矿区之一，同时也是西藏的政治经济文化中心，地域上包括拉萨、日喀则、山南、林芝的全部和那曲、昌都的部分县区，流域居民达200多万。该流域水体重金属污染不仅影响着该流域脆弱的生态系统，更影响着200多万居民的饮水安全，而且影响着整个西藏地区的经济建设、社会和谐和国家生态安全。本项目将依托申请人所在单位地利，将西藏"一江四河"流域高海拔高寒生态西宫作为研究对象，选择合适的研究地点，利用现代仪器分析技术对流域生态系统中的重金属赋存状况，迁移富集进行研究，并根据研究结果，选择不同区域合适的重金属生物指示物，结合各方面因素，对所研究生态系统进行重金属暴露风险评估及污染源解析。

Tibetan Plateau lies north of the Himalayas and it is one the coldest and most remote regions in the world. The study on the transport of heavy metals in this area is relatively scarce. With the rapid development of the mining industries, the corresponding heavy metal pollutions in Tibet are concerned. As the political, economic and cultural center of Tibet Autonomous Region, the valley of Brahmaputra (Yarlung Zangbo) River and its four branches is one of sixteen biggest mine area in China. The ecosystem safety in this area is not only related to the water safety of more than 2,000,000 residents of the valley, but also to the Tibet autonomous region's economic construction, social harmony, and national ecological safety. The purpose of the project is to study the distributions, patterns, transport, and bioaccumulations of heavy metals in this area, further to select appropriate bioindicators to monitor the heavy metal pollutions, and finally to identify the possible point sources and assess the risk of the selected areas.