摘要
湖泊水质是研究湖泊变化及其对气候变化响应的重要指标.分析了藏南羊卓雍错流域主要湖泊的水化学指标概况、水化学组成、矿化度时空分布及其驱动,并在此基础上对各湖泊的水质现状进行了评价.研究表明:流域内各湖泊水化学性质虽有一定的相似性,但矿化度等水化学指标浓度存在显著差异,各湖泊水化学组成亦差异显著.羊卓雍错和巴纠错均为硫酸盐类-镁组,沉错为硫酸盐类-钠组,普莫雍错和空姆错则分别为重碳酸盐类-镁组和重碳酸盐类-钙组.各湖泊矿化度差异较大的主要原因在于其补给来源不同,以降水补给为主的湖泊矿化度远高于以冰雪融水补给为主的湖泊.与全球气候变暖相对应,各湖泊矿化度变化反映了气候变化的影响,而水电站运行对羊卓雍错水体化学性质变化有所贡献.目前,羊卓雍错、普莫雍错水质为劣V类,空姆错、沉错、巴纠错水质为V类.深入探讨该流域水质对气候变化的响应,亟需更长时间序列的数据支持.为此,必须继续在该流域长期开展全方位的水化学观测与水质监测、评价工作.
Alpine lakes on the Tibetan Plateau are regarded as an important and sensitive indicator of global and regional climate change.As the basic prerequisite for researching lake variation and its response to climate change,the basic chemical parameters,hydrochemical type,mineralization change and its causes,and water quality evaluation are explored for the five major lakes（i.e.,Yamzhog Yumco,Kongmu Co,Chen Co,Bajiu Co and Puma Yumco） in Yamzhog Yumco basin in South Tibetan Region.The results are summarized as follows.Firstly,the concentrations of certain chemical parameters（e.g.,mineralization,major ions） are different remarkably among the five lakes.The water chemical properties of the five lakes,however,still have some similarities.With high alkalinity,the lake water in the basin contains low concentration of dissolved oxygen（DO）,fluoride,total phosphorus and total nitrogen,and trace amounts of selenium and other heavy metal ions.Secondly,the significant differences of hydrochemical types are also disclosed for the five lakes.The preponderant anion and cation of lake water in both of Yamzhog Yumco and Bajiu Co are SO2-4-Mg2＋,and in Chen Co,Kongmu Co and Puma Yumco are SO2-4-Na＋,HCO-3-Ca2＋,HCO-3-Mg2＋,respectively.Thirdly,there are disparate supply sources that cause obvious difference of mineral concentrations for the five lakes.The mineral concentration of Yamzhog Yumco,Bajiu Co and Chen Co supplied mainly by rainfall is much greater than that of Kongmu Co and Puma Yumco supplied by glacier and snow melt water.With global warming,the mineral concentration change of the lake water is influenced mainly by climate change in the sparsely populated alpine regions.Besides,the operation of Yamzhog Yumco Power Station has a negative impact on the lake water chemical property to some extent.At last,the water qualities of all the five lakes in the basin are evaluated to be unsatisfactory owing to high pH and low DO.In addition,it is the high mineralization that makes the lake water of Yamzhog Yumco,Chen Co and Bajiu Co neither drunk by local herdsmen and farmers residing nearby the alpine lakes,nor supplied for industrial and agricultural production.Lake water chemical parameter monitoring and water quality evaluation should be carried out continuously in the future,which will be beneficial to the investigation on water quality response to climate change in the alpine regions.
出处
《冰川冻土》
CSCD
北大核心
2012年第4期950-958,共9页
Journal of Glaciology and Geocryology
基金
国家自然科学基金项目(40871044
41171062)资助
关键词
高寒湖泊
水化学组成
矿化度
水质评价
羊卓雍错流域
alpine lakes； hydrochemical compositions； mineralization； water quality evaluation； Yamzhog Yumco basin；
