城市化对呼和浩特市潜水补给影响研究

城市化对地下水补给的影响已严重干扰了区域地下水均衡，引发了各种生态环境问题。在呼和浩特市自然地理及水文地质调查的基础上，运用GIS并结合地下水均衡计算的方法，探究城区扩张下以呼和浩特市为中心的研究区潜水补给量的变化。结果表明：从1986—2014年，研究区城镇面积扩大了约358倍。在城市化引起的地下水开采量增大、土地利用方式改变、景观河改造等因素影响下，研究区潜水疏干面积从119 1 km2扩大到10476 km2，年侧向补给量减少9 06115×104 m3；降水入渗补给量减少84385×104 m3；农灌水回渗补给量减少27944×104m3；河道渗漏补给量减少8638×104m3；城市供水管网漏失入渗量增加1 752×104m3。对比1986年和2014年，研究区潜水补给量从13 22501×104 m3减少至4 70703×104 m3，减少了644%，其中减少比例最大的是侧向补给量和降水入渗补给量。城市化使呼和浩特市潜水补给量大大缩减，迫切需要合理规划城市发展和地下水资源开采。

Influence of Urbanization on Unconfined Groundwater Recharge in Hohhot,Inner Mongolia

The impact of urbanization on groundwater recharge has seriously interfered with regional groundwater balance and triggered various ecological and environmental problems. Based on natural geographic and hydrogeological surveys, we study the urban expansion related changes in the unconfined groundwater recharge of the area around Hohhot, using GIS combined with groundwater budget calculation. The results show that the urban Hohhot had expanded by about 358 times from 1986 to 2014. Influenced by factors such as increasing groundwater exploitation, land use change and landscape river renovation, the drainage area of the study area had expanded from 1144 km2 to 10476 km2.Lateral recharge, rainfall infiltration recharge,irrigation water recharge and river seepage recharge had reduced for 9,06115×104 m3, 84385×104 m3, 27944×104 m3 and 8638×104 m3,respectively, whereas urban water supply network leakage infiltration had increased for 1,752×104 m3. Comparing 1986 with 2014, unconfined groundwater recharge of the study area had reduced from 13,22501×104 m3 to 4,70703×104 m3(ie, 644%), with the most important factors being lateral recharge and rainfall infiltration recharge. Urbanization has greatly reduced the unconfined groundwater recharge in Hohhot, and properly planned urban development and groundwater resource exploitation are necessary.