桂林市峰林平原区岩溶水文地球化学特征

峰林平原区往往作为岩溶地下水系统的主要径流、排泄地段且人类活动密集,其水文地球化学特征具有一定的独特性.对典型峰林平原区岩溶水文地球化学特征进行合理分析,不仅能够反应峰林平原区在丰水期的补给模式,而且也能够反应出人类活动对岩溶盆地中水化学组分的影响.通过对桂林市典型峰林平原区的补给区、内排泄区、补给径流区、排泄区岩溶地下水主要出露点和漓江上下游在丰水期与枯水期的野外取样、现场测试,对各化学指标进行空间和时间上的对比分析,结果表明:桂林市峰林平原区水文地球化学性质在丰水期与枯水期均呈现出明显的空间分布规律,且含水层介质岩性对地下水主要离子组分具有强烈的控制作用;丰水期的岩溶水文地球化学信息反应了在峰林平原区内排泄与补给径流区的补给模式以快速流为主,第四系土壤孔隙水垂向补给次之;桂林市峰林平原区人类活动对岩溶水化学性质具有一定的影响,主要为生活污染与农业污染,其重点防护区为内排泄区与补给径流区.

Hydrogeochemical Characteristics of Peak Forest Plain in Guilin City, China

Peak plain is generally regarded as the main runoff area, drainage area and massive human activities site in karst groundwater system. The hydrogeochemical characteristics of peak plain are unique. The reasonable analysis of hydrogeochemical characteristics for typical peak forest plain area, can not only reflect the recharge patterns of this area in rainy season, but also present the influence of human activities on water chemistry component in karst basin. Field sampling and field testing were conducted in both rainy season and dry season, in recharge area, internal drainage area, runoff area, drainage area, the main spouts area of karst groundwater, upstream, and downstream of the Lijiang River. Besides, through the comparative analysis of the chemical indicators of space and time, the research shows some obvious pattern for the hydrogeochemical properties of peak forest plain in Guilin City, China during rainy season and dry season. The results also make it clear that the aquifer medium plays an important role in controlling the major ions compositions of groundwater. The karst hydrogeochemistry information of rainy season can reflect that the rapid flow is the main recharge flow in excretion and runoff zones in the peak forest plain area, followed by the Quaternary soil interstitial water. The human activities of Guilin plain peak forest have certain impacts on the chemical properties of karst water. Human activities lead to domestic pollution and agricultural pollution. It is also clear that the key protection zones should be the internal drainage area and recharge runoff area.