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利用自然界中广泛分布的环境同位素进行湖泊水体演化过程分析已经成为现代湖泊科学的重要研究方向.通过采集内蒙古达里诺尔湖(简称“达里湖”)2013年1月份的湖冰、湖水,2012年夏季湖水与湖区大气降水等,共分析了77个样品中稳定氢(H)、氧(O)同位素值的变化情况,在此基础上对达里湖水体稳定H、O同位素组成变化及其对结冰过程的响应进行了详细分析,结果显示:(1)伴随结冰过程的完成,各站点深层冰体(厚度~65cm)中δD、δ~(18) O值比表层冰体(厚度~15cm)中的值出现不同幅度的偏重.而冰下水体中δD、δ~(18) O平均值则比冰体中的平均值分别偏轻约13.85‰、2.23‰.在冰层形成的快速与稳定阶段,δD、δ~(18) O值的变化幅度也存在差异.同时,冬季外源水体的输入对各站点间同位素值差异的影响比夏季更明显;(2)夏季湖水、冬季湖水与湖冰的同位素值均落在全球大气降水线与湖区大气降水线之外,显示湖泊冰封之前,蒸发对湖泊水体同位素偏移存在一定程度的影响;而冬季湖水与湖冰的同位素值基本位于同一斜率区间,且全部落在夏季湖水同位素值的右侧,显示两者之间并不存在明显的蒸发分馏作用,造成上述现象的因素只能归结于结冰过程.
The analysis of lake water evolution using the widely distributed environmental isotopes in nature has become an important research direction of modern lake science.By collecting the lake ice and lake water of Dalinuoer Lake in Inner Mongolia in January 2013, , The summer precipitation in summer 2012 and the atmospheric precipitation in the lake area. The changes of stable hydrogen (H) and oxygen (O) isotopes in 77 samples were analyzed. Based on this, the stable H and O isotopic compositions The results show that: (1) With the completion of the icing process, the δD and δ ~ (18) O values of the deep ice body (thickness ~ 65cm) (Thickness ~ 15cm), while δD and δ ~ (18) O in ice bodies are slightly less than the average values of ice body, about 13.85 ‰ and 2.23 ‰, respectively. In the ice layer In the rapid and stable stages of formation, the δD and δ ~ (18) O values also vary in magnitude, and the input of exogenous water in winter has more obvious effect on the differences of isotopic values among sites than in summer. (2) , The isotopic values of winter lake and lake ice all fall within the global atmospheric precipitation line Before the lake was frozen, the evaporation had a certain degree of influence on the isotopic shifts of lake water. However, the isotopic values of winter lake and lake ice were basically in the same slope range, and all of them landed on the isotopic values of summer lake water On the right, it shows that there is no obvious evaporative fractionation between the two. The factors that cause the above phenomenon can only be attributed to the icing process.