大武水源地地下水中NO3-N动态变化特征及其影响因素分析

Dynamic Variation Characteristics of NO_3-N in Groundwater of Dawu Water Source and Influencing Factors

利用GIS空间分析平台的反距离权重法插值获取中国北方典型大武岩溶水源地年内和年际地下水中NO_3-N浓度空间分布特征,并利用斯皮尔曼相关系数获取2009年地下水中NO_3-N浓度与地下水脆弱性各影响因子的相关性。经分析可知:(1)综合以往研究资料,大武水源地地下水中NO_3-N演化过程分为恶化初期、恶化中末期和恢复阶段,且地下水水化学演化过程要滞后于地下水水动力过程的演化;(2)年内地下水中NO_3-N浓度的变化主要受到降水的影响,年际间地下水中NO_3-N浓度的时空变化特征很容易受到地下水系统动态因子的影响,包括地下水资源的开发利用和可变的下垫面条件;因此,人类活动朝着优化地下水环境的方向努力,可促进岩溶水资源的可持续开发利用。

This paper used the Inverse Distance Weighted （IDW） based on GIS spatial analyst platform to obtain the spatial distribution characteristic of NO3-N of a typical karst water source in the North China, and used Spearman＇s coefficient to obtain the relationship between the concentration of NO3-N in 2009 and various influencing factors of groundwater vulnerability. By combining with research data in the past, it can be known that the evolution process of NO3 -N in Dawu water source can be classified into early deterioration period, the mid-end deterioration period and the recovery stage, and the evolution process of groundwater chemicals lagged behind groundwater dynamics. It can be also concluded that the spatial distribution of NO3 -N values in a year is mainly influenced by precipitation, while the spatial distribution of NO3-N values of inter-annual is easily influenced by dynamic factors of groundwater system including the exploration of groundwater resource and variable underlying surface conditions, the human activities develop in the direction of optimizing groundwater environment will promote the sustainable development of karst water resources.