氚同位素在黑河流域水循环研究中的应用  

APPLICATION OF RADIOACTIVE TRITUIUM ISOTOPE IN STUDYING WATER CYCLE OF THE HEIHE RIVER BASIN

作　　者：赵良菊[1] 阮云峰[1,2] 肖洪浪[1] 周茅先[1] 程国栋[3] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所中国科学院内陆河流域生态水文重点实验室,兰州730000 [2]中国科学院大学,北京100049 [3]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,兰州730000

出　　处：《第四纪研究》2014年第5期959-972,共14页Quaternary Sciences

基　　金：国家自然科学基金项目(批准号:91325102,41171167,91025016和91125025)资助

摘　　要：通过对黑河流域不同水体如降水、河水、深井(>80m)、浅井(<80m)及泉水的氚(T)含量的测定,结合文献资料和国际原子能机构数据,对流域不同水体氚(T)含量的空间分布特征进行了分析,并对黑河流域浅层和深层地下水的补给来源、年龄及其更新时间进行了研究。结果表明:1)黑河上游、中游及下游河水T含量分别为50.0TU,33.3TU及20.9TU,呈逐渐降低趋势;上游和中游降水T含量变化也呈相似的规律,说明黑河流域河水来自黑河源区降水,且河水从上游到下游流动过程中与地下水进行转换。尤其是在临泽到正义峡段,河水的平均T含量为31.9TU,说明张掖和临泽灌溉抽提的地下水对河水有补给作用。2)黑河上游和中游山前平原的深层地下水T含量大于30.0TU,补给年龄小于50a;中游盆地及下游深层地下水T含量低于10.0TU,地下水年龄在50a以上,为次现代水,更新速度慢。3)黑河上游地下水和河道附近区域的浅层地下水的T含量高于30.0TU,补给年龄低于50a;远离河道浅层地下水T含量低于10.0TU,补给年龄大于50a。说明黑河源区降水是上游地下水的补给源,出山径流是黑河干流附近浅层地下水的主要补给源,地下水补给年龄低于50a,更新期短;远离河道区域的浅层地下水T含量低于10.0TU,为次现代水,更新速度慢。本研究结果对合理科学地利用黑河流域水资源具有借鉴意义。Based on the measurement of tritium concentration （T） in different water pools （133 samples） such as precipitation,river water and groundwater （deep ground water,＞80m; shallow groundwater,＜80m） of the Heihe River basin （37°45′～42°40′N,96°42′～ 102°04′E） and the data sets from published references （235 samples） and data of GNIP of IAEA,we explored the spatial distributions of T concentration of different water pools,and discussed the recharge source,rate and age of deep and shallow groundwater of the Heihe River basin.The results showed that：（1） The T concentrations in river water of the upper,middle and lower reaches are 50.0TU,33.3TU and 20.9TU,respectively,showing a decreasing trend.The T concentration of precipitation of upper and middle reaches revealed similar trends,indicating the river water mainly came from rainfall in upper reaches and there was exchange between river water and groundwater from the movement water flow.Especially in the region between Linze and Zhengyixia,the T concentration in river water was 31.9TU,suggesting the recharge to river occurred by the irrigation used the groundwater in Zhangye and Linze.（2） The T concentration of deep groundwater of the upper and middle reaches was above 30.0TU,and the recharge ages are less than 50a.The T concentration of deep groundwater of basin in middle reaches and lower reaches were lower than 10.0TU,suggesting that the age of groundwater beyond 50a and recharge rate was very slow.（3） The T concentrations of groundwater of upper reaches and shallow groundwater near to the river channel were above 30.0TU,indicating that the recharge ages of groundwater were less than 50a,and the renewal rate were high.The low T concentrations （lower than 10.0TU） of the shallow groundwater far from the river were found,revealing the age of shallow groundwater in these regions were recharged before 1950s with low renewal rate.Our results provide significant scientific instructions for reasonable management of the wa

关 键 词：黑河流域 氚同位素 地下水补给源 地下水年龄 

分 类 号：P641.3[天文地球—地质矿产勘探]