黑河中游过去20年地下水位空间变异性分析

以西北内陆干旱区黑河中游为研究对象,基于1985年和2005年地下水位观测资料,利用地理信息系统(GIS)和地统计学(Geostatistics)方法,综合分析了过去20年来地下水空间变异规律。结果表明:黑河中游近20年来地下水位空间相关性减弱,局部异质性增强,地下水的连通性和脆弱性增加,冲积扇中上部地下水补给区的水位下降(5～15 m)显著,冲积扇下部和河谷细土平原地下水消耗区水位稳定下降,河谷盆地和河谷平原区同时存在水位上升现象,产生了环境地质灾害。因此,为了保持干旱区内陆河流域可持续发展,需要从多角度分析流域的水资源变异规律,合理配置干旱内陆河流域水资源,针对局部环境地质灾害尽快采取相应措施。

Spatial variation of ground water in middle stream of the Heihe River basin during past two decades

Middle stream of the Heihe River basin(HR-MR),located in northwestern China,was selected as the study area.On the basis of long-term observated groundwater level data in 1985 and 2005,Geographic Information System(GIS) and geostatistical method were applied to synthetically analyze the spatial distribution of groundwater table during the past 20 years.The results showed that changes of groundwater level occurred in the study area during the past 20 years.The auto-correlation between groundwater tables become weaker.Groundwater connectivity become stronger and the vulnerability of groundwater increased.Groundwater level in the middle and upper reaches of the alluvial fan decreased obviously(5~15m),while that in lower reach of the alluvial fan and the river valley plain exhibited an increasing trend.Therefore,more rational water resources management in the study area is required for maintaining sustainable development,especially for more reasonable measures to mitigate geological disasters in arid inland river basin.