基于极度干旱条件下的喀斯特峡谷区水资源利用方式——以贵州花江峡谷示范区为例

Water Resources Using Methods under Extreme Drought Conditions in Karst Gorge Areas:Taking Huajiang Gorge Demonstration Area in Guizhou for Example

为解决气候极度干旱条件下喀斯特峡谷地区农村饮用安全问题,以贵州花江示范区为例,分析了不同干旱情景下水资源利用方式及其供需平衡情况。结果显示:研究区一般干旱持续时间为4个月,水窖(池)雨季存储表层泉点水量约1.29万m3,靠此能满足人畜饮水(1.11万m3)需求;但气候极端干旱持续时间超过8个月,降雨减少,地表水水量衰减快,可蓄存水量为一般干旱年份的55%,仅能支撑到2月中旬,极度缺水时间约75d。为此,通过机井方式在附近区找到极度干旱情形下流量稳定的地下水,采取"集中引水,分散供水",市场化统一管理方式,保证了研究区3 850人极度干旱条件下饮水安全。其成本远低于分散的小微型蓄水工程投资总和,是考虑极度干旱情景下喀斯特山区解决饮水安全的有效方式。

In order to solve the safety problem of rural drinking water in Karst gorge areas ,this paper analyzes water resources utili‐zation and balance between supply and demand in different drought conditions by taking Huajiang gorge demonstration area in Guizhou as an example ,.The results show that the general drought duration of the study area is about 4 months ,cistern （pool） could storage about 12 900 m3 surface water in rainy seasons ,which can meet the demand of drinking water for people and livestock （11 100 m3 ） .However ,with the decrease in rainfall ,extreme arid duration exceeds 8 months ,the surface water can decay quickly , and only 55% of water in dry years can be stored ,which can barely last until mid-February .Therefore ,there is a water shortage pe‐riod of about 75 days .Thus ,it is significant to find groundwater by taking advantage of“Concentrated water diversion ,decentralized water supply” to ensure 3 850 people＇s drinking water safety in extreme drought conditions through a unified market management mode .Its cost is much lower than the sum of project investment of small and micro storage .And it is an effective way to solve the problem of drinking water safety under extreme drought conditions in Karst mountainous areas .