大兴区长期地下水资源开发利用程度变化研究

Evaluation and sustainable exploitation and utilization of groundwater resources in Daxing District

为探究大兴区长期地下水资源开发利用程度变化,结合1980—2020年大兴区地下水位、水量数据,基于ArcGIS空间插值和地下水均衡原理,对大兴区地下水资源量和地下水资源开发利用程度进行评价和分析。大兴区自20世纪80年代以来,地下水位总体呈现下降趋势,2006年后由于采取限采措施及再生水大量用于农业灌溉和生态,地下水位趋于稳定,至2015年,区域地下水平均埋深17.50m;南水北调入京后,地下水位埋深进一步得到回升;研究区多年平均地下水总补给量为2.47亿m^(3),多年平均地下水开采量为2.74亿m^(3),地下水开发利用率达到123.76%;南水入京后,研究区用水量总体呈现减少的趋势,其中居民生活用水和生态环境用水处于增加的趋势,工业用水、农业用水、公共服务用水处于减少的趋势。地下水高开发利用率和地层结构上下联系度差,是造成研究区自2000年以来持续处于超采状态的主要原因;因此要实现区域地下水的可持续利用,一方面要扩大南水北调的供水范围,同时加大对非常规水源使用的探索研究;另一方面需从城市规划层面限制人口和城市的无序扩张。相关研究成果可为大兴区地下水资源管理、节水型社会建设提供借鉴。

This paper explored the changes of long-term development and utilization of groundwater resources in Daxing District.Combining with the data of groundwater level and water volume in Daxing District from 1980 to 2020,the amount of groundwater resources and the development and utilization of groundwater resources in Daxing District were evaluated and analyzed based on Arcgis spatial interpolation and groundwater balance calculation.Since the 1980s,the annual average groundwater level in Dax ing District has generally shown a downward trend.After 2006,taking measures to limit groundwater exploitation and developing reclaimed water irrigation vigorously made the ground water level tend to be stable,which is about 17.5 m in 2015.After the South-to-North water transfer into Beijing,the water table depth has been further recovered.The average annual recharge of groundwater is 247 million m^(3) and the average annual ground water extraction volume reached 274 million m^(3),with the utilization rate of groundwater development reaches 123.76%.After the South-to-North water transfer to Beijing,the water consumption in the study area generally showed a decreasing trend,among which the domestic water consumption and ecological environment water consumption were on the increase,and the industrial water,agricultural water,and public service water were on the decrease.The high utilization rate of groundwater development and the poor connection degree between the upper and lower strata structure are the main reasons for the continuous overproduction in the study area since 2000.Therefore,in order to realize the sustainable utilization of regional ground water,it is necessary to expand the water supply scope of the South-to-North water diversion project,and increase the exploration and research on the use of unconventional water sources.The relevant research results can provide reference for groundwater water resources management and water-saving society construction in Daxing District.