摘要
运用环境同位素和水化学技术,通过现场测试和室内分析,研究了银川平原不同水体的氢、氧同位素和基本水化学参数特征,结果表明：银川平原各水体δ^（18）、δD值基本分布在当地降水线和黄河水δD-δ^（18）关系线下方,由于湖水受到强烈的蒸发作用,与其他各地表水相比同位素组成明显偏正,但其氘盈余（负值）远低于全球降水线;同位素特征显示,地表水和地下水均接受黄河水补给,其中河水、渠水和部分地下水的同位素组成一致,表明地表水与地下水之间水力联系十分密切;研究区地下水δ^（17）-δ^（18）拟合线[ln（δ^（17）＋1）=0.524ln（δ^（18）＋1）＋0.000 94]和全球降水线[ln（δ^（17）＋1）=0.528ln（δ^（18）＋1）＋0.000 33]相近,但（17）O盈余大于海水;银川平原各水体均呈碱性,水体的化学类型主要有HCO3-Na、HCO3-Ca·Mg,阳离子以Na＋为主,阴离子以HCO3-为主。Gibbs图显示各水体离子组成主要与岩石风化、蒸发结晶有关。
Hydrochemical technology and environmental isotopes were used to analyze the hydrogen and oxygen isotopes and hydrochemical properties of water samples from the Yinchuan Plain. The research showed that the δD and δ^（18 ）O values of stream systems in the plain were distributed below the local meteoric water line（ LMWL） and theδD-δ^（18 ）O relationship line of Yellow River water. Compared with other kinds of surface water,the isotopic composition of lake water was more positive,and the d-excess（ negative） was far lower than that of global meteoric water line（ GMWL） due to the strong evaporation. According to the isotopic characteristics,both surface water and groundwater were recharged by the Yellow River. The consistent isotopic composition of river water,canal water and groundwater indicated that the hydraulic connection between surface water and groundwater was very close. The correlation between δ^（17 ）O and δ^（18 ）O followed an equation of ln（ δ^（17 ）O ＋ 1） = 0. 524 ln（ δ^（18 ）O ＋ 1） ＋ 0. 000 94,which was similar to the global meteoric water line [ln（ δ^（17 ）O ＋ 1） = 0. 528 ln（ δ^（18 ）O ＋ 1） ＋ 0. 000 33],but the^（17 ）O-excess was higher than that of seawater. The waters in the Yinchuan Plain are alkaline. The conductivity of lake water was the highest,then that of groundwater,and that of river water was the lowest. The chemical types of the waters included mainly HCO3-Na and HCO3-Ca·Mg,and the main cation and anion were Na~＋and HCO3^-,respectively.The Gibbs plot revealed that the chemical compositions of the water samples were mainly affected by rock weathering and evaporation. The hydrogen and oxygen isotopes and hydrochemical data indicated that the water hydraulic connection between surface water and groundwater was strong.
作者
范广群
张德忠
张建明
桑文翠
赵力强
FAN Guang-qun;ZHANG De-zhong;ZHANG Jian-ming;SANG Wen-cui;ZHAO Li-qiang(College of Resources and Environmental Sciences,Lanzhou University,Lanzhou 730000,Gansu,China;Gansu Province Institute of Geological Environment Monitoring,Lanzhou 730000,Gansu,China)
出处
《干旱区研究》
CSCD
北大核心
2018年第5期1040-1049,共10页
Arid Zone Research
基金
国家自然科学基金(41201197)
中央高校基本科研业务费专项基金(lzujbky-2014-211)资助
关键词
水体
氢、氧同位素
水化学
黄河水
17^O盈余
银川平原
water body
hydrogen and oxygen isotope
hydrochemistry
Yellow River water
17^O-excess
Yinchuan Plain
