中文摘要：

蒙新高原位于干旱/半干旱气候区,区内湖泊众多,但多为盐湖和咸水湖.近年来,由于湖泊咸化、萎缩甚至干涸的过程加快,区内多数湖泊水资源严重短缺,湖泊及其流域的生态环境遭遇巨大破坏.本文选取蒙新地区11个淡水和微咸水湖泊,通过对不同区域和不同类型的湖泊水质状况分析和对比研究,揭示蒙新地区湖泊水质现状及其变化特征与原因.结果表明,新疆地区湖泊类型多样,湖水阴、阳离子涵盖了各种水化学类型,而内蒙湖泊均为钠组-氯化物型.不同湖泊间湖水离子浓度和矿化度差异较大,湖水交换是蒙新地区湖泊水体矿化度的主要影响因素;与1988年相比,哈纳斯湖、阜康天池和赛里木湖等山地湖泊矿化度无明显变化或呈下降趋势,反映了区域气候变化特征;柴窝堡湖和红碱淖湖水矿化度快速升高,而达里诺尔水体矿化度增幅较小,其差异反映了修筑水库、地下水开采等人类活动在湖泊水环境变化中的不同作用.近50年来,乌伦古湖、博斯腾湖、吉力湖和乌梁素海水体矿化度波动升高,尤其近年来矿化度升高趋势加快,反映了流域内工农业等人类活动增强而导致入湖污染物增加以及气候干旱引起湖水浓缩两个方面所产生的叠加效应.

英文摘要：

Lakes are abundant in the arid/semi-arid region of Inner Mongolia-Xinjiang Plateau,but many of them are salt lakes and saline lakes so that the lake water resources are poor.In recent years,most lakes in the region have quickly becoming salty,area withered and dry,which greatly damaged the ecological environments of the lakes and their catchments.Eleven fresh and slight saline lakes in this region were chosen to investigate.Based on the analysis of the water quality status and their discrepancy,the characteristics and reasons of the water quality variety were explored.Our results showed that Na＋ and SO2-4 were the dominant ions within the lake water of Inner Mongolia,while the lake water in Xinjiang were dominant by multiple ions.The ions and total disolved solid concentrations （TDS） of lake water were different with the water exchange variety.TDSs of lakes surround by mountains,including Lake Kanasi,Fukangtianchi and Sailimu Lake,were stable between 1988 and 2008,which reflected the climate change of the region.The TDSs of Lake Caiwopu and Lake Hongjiannao increased quickly while that of Dalinuo increased slowly,which were impacted by anthropic activates including reservoir building and groundwater exploitation.During the past fifty years,fluctuations of the TDS concentrations in Lake Wulungu,Lake Bosten,Lake Jili and Lake Ulansuhai raised and increased recently because of climatic drying and the development of industry and agriculture.