大安市地下水动态变化趋势及驱动因素研究

为研究大安市地下水位的变化特征及其主要控制因素,根据大安市气候因素、引水灌溉水量、地下水开采和地下水埋深等数据资料,分析了环境因素的变化规律及趋势,基于suffer软件利用克里格方法对地下水埋深进行插值,分析其时空演变规律及驱动因素。结果表明,降水量呈波动增加的趋势,平均年降水量增量为0.249mm/a;蒸发量呈波动下降的趋势,平均年蒸发量增量为-2.063mm/a;引水灌溉水量呈增加趋势,平均年灌溉水量增量为0.212×108m/a。潜水埋深呈小幅度减小趋势,年均倾斜率为-0.023m/a,承压水埋深呈波动上升趋势,年均倾斜率为0.146m/a。承压水动态变化的驱动因子由大到小依次为人工开采(主要是农业开采与生活用水)、引水灌溉、降水、蒸发,农业开采是最主要的影响因子。研究结果可为制定完善的水资源调控方案提供理论依据。

Analysis of Variation Trend and Driving Factors of Groundwater Dynamic in Da'an City

The purpose of the paper is to study the variation trend of groundwater dynamic in Da''an City and analyze the degree of the influences on it. According to the data of climate and surface water irrigation, groundwater exploitation, and groundwater depth, this paper analyzed the tendency of environmental factors and the temporal and spatial evolution of the groundwater depth by means of suffer software and kriging methods, and then identified the main factors for deriving change in groundwater depth. The results show that the precipitation presents a fluctuated increasing trend and its average increase slope is 0.249mm/a, the evaporation shows a fluctuated decreasing trend and its average decrease slope is -2.063mm/a, the irrigation areas tend to a great increase and its average increase slope is 17.933acre/a. The unconfined groundwater depth exhibits a less decline tendency and its average decrease slope is -0.023m/a, and the confined groundwater depth presents a fluctuated increasing trend and its average increase slope is 0.146m/a. The main driving factors of confined groundwater dynamics are as follows: groundwater exploitation, surface water irrigation, precipitation, evaporation, and the groundwater withdrawal for agricultural irrigation is the most important factor. The study results could provide theoretical support for policymakers to develop comprehensive program of configuration control of water resource.