石羊河流域水资源开发利用与补给之间的协调性评判

在甘肃省石羊河流域历史水资源开发利用情况简述基础上,结合城镇化进程,提出目前武威市的农业用水来源于祁连山山前水库拦蓄地表水,景电二期延伸工程向民勤所调黄河水及部分地方开采地下水;工业、生活用水均取自地下水,水量供给与天然补给上已处于严重失调状态。就城市地下水源地保护区划分而言,以传统的地下水开采影响半径为基本依据所进行的现代地下水源地保护区划分是不合理、不够科学的,应当在地下水补给、径流、排泄条件分析基础上,将水源地上游整个流域划定为保护区,以永久性解决城市地下水供水中存在的水源地安全问题。另外,针对石羊河流域重点治理规划中的调水方案,比较科学、合理的做法是：应从石羊河流域地下水文地质条件出发,遵循第四世地质历史时期形成的地下水补给、径流、排泄通道,在全流域实施压减灌溉面积、减少地下水开采量的同时,将景电二期延伸工程所调黄河水与祁连山山前部分水库地表水部分地或全部地从石羊河上游———武威盆地上游区域通过灌溉或其它方式下渗,补给进入地下水系统中,最终达到六河水系及下游地下水位停止下降,石羊河下游民勤盆地地下水位持续回升的综合治理规划目标,而不是将水直接调入下游民勤盆地。

EVALUATING BALANCES BETWEEN WATER RESOURCES DEVELOPMENT AND SUPPLEMENT IN SHIYANGHE WATERSHED

Based on the history of water resources development and utilization in the Shiyanghe River Basin, combined with the urbanization process, we conclude that the agricultural water source of Wuwei city come from surface water in the reservoirs before Qilian Mountains, the tune of water of the Jingtai phase-two-extension project in the Yellow River and some local exploitation of groundwater; industrial and domestic water all come from groundwater, that water supplying and the natural supply of water source has been a serious imbalance. To the division for city groundwater protection area, we think that it is unreasonable and unscientific to divide modern groundwater protection areas according to the traditional groundwater influence radius in groundwater mining . Based on the analysis of the hydro-geological conditions of water source site, groundwater recharge, runoff and drainage, we should take the river basin delineation of upstream as a big protection area, so as to solve the permanent security problems of city water supply. In addition, in water diversion project according to the ＂ Important management and planning in Shiyanghe River basin of Gansu Province＂, we considered to he more scientific, reasonable approach is that based on the analysis of the groundwater hydro-geological conditions of the Shiyanghe River Basin, following the groundwater recharge, runoff, drainage channels which were formed during the Article IV geological historical period, concentrated into the implementation irrigation area and reducing the exploitation of groundwater in the whole basin at the same time, we should partially or entirely take use of the tune of water of the Jingtai phase-two-extension project in the Yellow River and surface water in the reservoirs before Qilian Mountains from the upper Shiyang River basin -- Wuwei upstream region by irrigation or other means to infiltrate and recharge the groundwater system, enter, so as to arrive eventually into the six downstream rivers , to stop groundwater level falling, and to recovery sustainably the Minqin Basin groundwater level,instead of directly transferring water source into the Minqin basin.