基于氢氧稳定同位素的艾比湖流域地表水与地下水转化关系

Transformation Between Surface Water and Groundwater in Ebinur Lake Basin Based on Hydrogen and Oxygen Stable Isotopes

地表水和地下水是水资源主要组成部分,研究干旱区地表水和地下水相互转化过程,对水资源的合理开发利用与评价具有重要的理论意义。选取艾比湖流域地表水和地下水为研究对象,分析其稳定同位素组成特征和分布规律,探讨不同水体间补给关系。结果表明:(1)艾比湖流域大气降水δ^(2)H和δ^(18)O表现出显著的季节变化特征,全年表现为冬季贫化夏季富集的现象。(2)湖水δ^(2)H和δ^(18)O值明显高于河水,反映湖水强烈的蒸发浓缩作用。博尔塔拉河和精河水的δ^(2)H和δ^(18)O值从上游到下游总体趋于富集,在山区、绿洲和平原表现出不同的同位素组成。地下水同位素值上游山区最低,中间平原次之,艾比湖周边最高。(3)博尔塔拉河上游地下水与河水交换比例较大,为63.0%;中下游河水和地下水之间交换比例较低,分别为5.0%~33.0%和2.5%~26.0%。精河深层地下水由浅层地下水和河水共同补给,比例分别为73.3%和26.7%。艾比湖周边,潜水流受到阻隔出露成泉水,与河水共同补给湖水。该研究揭示了艾比湖流域地表水和地下水相互转化关系,可为流域的水资源管理和生态环境建设提供科学支撑。

Surface water and groundwater are the main components of water resources.It is of great theoretical significance to study the mutual transformation process of surface water and groundwater in arid areas for the rational development,utilization,and evaluation of water resources.Based on surface water and groundwater in Ebinur Lake basin,the stable isotope composition characteristics,distribution law,and the recharge relations of different water types were discussed.Results showed that:(1)The δ^(2)H and δ^(18)O values of precipitation in the Ebinur Lake basin showed significant seasonal variation,presenting dilution in winter and enrichment in summer through the whole year.(2)In the Ebinur Lake basin,the stable isotopes values of lake were significantly higher than that of river,which reflects the strong water evaporation concentration of lake.In Bortala river and Jinghe river,the δ^(2)H and δ^(18)O from upstream to downstream tended to enrichment,but it showed different features among the areas of mountain,oasis and plains.The δ^(2)H and δ^(18)O of groundwater presented the minimum in mountainous part,the middle in plains,and the highest surrounding the Ebinur Lake.(3)In Bortala river,the exchange proportion of groundwater and river water in the upper reaches was large,which was 63.0%.The exchange ratios in the middle and lower reaches were relatively low,which were 5.0% to 33.0% and 2.5% to 26.0%,respectively.In Jinghe river,the deep groundwater was replenished by shallow groundwater and river water,the recharge ratios were 73.3% and 26.7%,respectively.In the vicinity of Ebinur Lake,the diving flow was cut off and exposed to spring water,which supplies the lake with the river water.The study revealed the exchange relationship between surface water and groundwater in Ebinur Lake basin,which can provide scientific support for water resource management and ecological environment construction of the Ebinur Lake basin.