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青海湖湖水季节性和空间上的变化特征对青海湖沉积物中自生碳酸盐形成过程及环境意义的理解、湖泊的演变趋势具有重要的指导意义.本文通过沉积物捕获器采集了为期一年每月一次的青海湖季节性的湖水,并采集了青海湖和周围子湖空间分布上的湖水样品.对季节性样品阳离子的分析显示,青海湖湖水中的阳离子在旱季(12月至次年4月)达到最高值,在雨季逐渐降低.湖水的Ca^2+和Mg^2+从2-3月份逐步降低,表明自生碳酸盐开始沉淀,并且在雨季来临时沉淀持续大量发生.而在雨季后期,则可能发生含Mg碳酸盐的部分溶解.空间分布的样品分析显示,青海湖可能经历了太阳湖和月牙湖的水化学阶段,在未来的演变过程中,湖水的Ca^2+和Sr^2+受自生碳酸盐沉淀的控制而保持基本稳定,Mg^2+、Na+、K+则将持续增加,其水化学将朝着当前海晏湾,并进一步朝尕海湖水的方向演变.本文的研究还进一步暗示了在长时间尺度上自生碳酸盐形成对气候变化的可能响应. “,”Seasonal and spatial variation characteristics of lake water within the Lake Qinghai catchment are of significance for understanding precipitation process and environmental significance of authigenic carbonates and the lake's evolution trend. In this study, seasonal lake waters were collected once a month over a whole year period by a sediment trap in Lake Qinghai, and spatial samples were collected in Lake Qinghai and its satellite lakes. The analyses for seasonal samples showed that the cations reached the highest values during the dry season (December to next April), and decreased during the rainy season. Ca-and/or Mg-carbonate precipitation started from February to March, and such precipitation process would reach maximum during the rainy season, resulting in stable concentrations of Ca^2+ and Mg^2+. During the late rainy season, partial dissolution of Mg-containing carbonates might also happened. The analyses for spatial water samples showed that Ca^2+ and Sr^2+ concentrations of lake water would be basically stable owing to precipitation of authigenic carbonates, whereas Mg^2+ , Na + , and K + would continue to accumulate in the future evolution processes of Lake Qinghai. Its water chemistry will change towards that of Haiyan-wan Lake and further towards that of Gahai Lake. This study further reveals the potential response of authigenic carbonate precipitation to climate change over a longer time scale.