甘肃西部平原区地下水同位素特征及更新性

Isotopic characteristics of groundwater and its renewal in the plain area of western Gansu.

大量同位素资料研究表明,甘肃西部黑河流域南部平原区地下水补给和更新的特征是,具有非均一性和有限性;潜水较年轻又更新快,承压水较老又更新慢;东部地下水更新较快,西部更新较慢;祁连山前戈壁带地下水更新较快,细土平原更新较慢;近河道带地下水更新速率大,远离河道则小。上述特征与出山地表径流量及其补给源属性密切相关。因此,结合地下水更新特征,充分利用祁连山前戈壁带较强的入渗条件和调蓄功能,与地表水联合优化调控,有利于该区水资源可持续利用。

A wealth of isotope date indicate the following: the groundwater recharge and renewal in the plain area in the southern part of the Heihe River basin are nonuniform and limited; the phreatic water is younger and renewed more rapidly than confined groundwater; the groundwater in the eastern area of the middle reaches is renewed more rapidly than in the western area; groundwater in the gobi zone in the front of the Qilian Mountains is renewed more rapidly than that in the fine soil plain; and groundwater near the riverbed is renewed more rapidly than that far from the riverbed. The above-mentioned characteristics are closely related to the surface runoff out of the mountains and the attribute of the recharge resource of groundwater. Therefore it is beneficial to groundwater resources sustainable utilization to make full use of the strong infiltration and groundwater regulating and storing functions of the gobi zone in the piedmont plain of the Qilian Mountains, combined with the groundwater renewal characteristics and surface water regulation.