黑河实施分水后中游灌区地下水资源量的变化分析

Analysis of the Change of Groundwater Resources due to Water Allocation in the Irrigation Areas of the Middle Heihe River

黑河中游地下水是农业灌溉的重要水源之一，而黑河分水通过对地表水的影响，进而影响地下水资源，根据中游地下水观测数据，运用Kriging空间插值法，对分水前的20世纪90年代和分水后的2004-2005年间的地下水位和储量变化进行对比分析，结果表明：中游甘州区、临泽县和高台县地下水位不同程度上都在下降，其范围在1.3～2.7m，地下水可开采储量也随之减少，估算减少总量约为8.23×10^8m^3，究其原因，一方面是由于分水使得地表水转化为地下水的数量减少，占总减少量的45％；另一方面，河水供给的减少促使中游地区在农业灌溉中转而大量开采地下水所致，目前中游地区调整产业结构，减少农业用水是分水后保持当地各种环境稳定的重要措施。

Groundwater is the influential irrigation resources for the middle reaches of Heihe River, and will be governed by the surface water after water allocation to the western and eastern Juyan Lake. Based on groundwater observation data, and using ordinary Kriging interpolation, the changes of groundwater tables and volumes before the 1990s and from 2004 to the 2005 a were analyzed. The analyses show that groundwater tables in Ganzhou District of Zhangye Municipality, Linze and Gaotai Counties had dropped 1.3～2.7 m with a local differentiation. Consequently the groundwater reserves declined by about 8.23～10^8m^3. This may be attributed to the reduction of transformation of surface water to groundwater, which accounts for 45% of the total decrease, and the resultant enhanced exploitation of groundwater for agriculture irrigation in the middle reaches of Heihe River after the river runoff being substantially diverted. As a result, the volume of groundwater is decreasing and the groundwater resources are degrading in the Middle Heihe River. Currently, readjustment of the industrial structure and saving the agriculture water are significant measures to hold all environments stably.