广东英德宝晶宫洞穴滴水元素季节变化与影响因素

Seasonal Variations and Controlling Factors of the Element Contents in Drip Waters Collected from the Baojinggong Cave in Guangdong Province

为揭示洞穴滴水元素的季节变化特征及其影响因素,从2011年12月至2013年5月对广东英德宝晶宫洞穴内的3个滴水点滴水中的Ba、Sr、Ca、Mg元素进行为期一年半的监测,结果发现:13个滴水点滴水中的元素浓度基本上都表现出明显的季节变化特征,但不同的元素之间和不同的滴水点之间的季节变化趋势存在差异,表明不同的滴水点其不同的元素浓度变化的影响机制各有不同.2强降水对洞穴滴水的元素浓度具有稀释作用,Drip1和Drip2各元素浓度在有强降雨的5、6月都呈现低值.33个滴水点的Mg/Ca和Sr/Ca比值都具有较强的正相关关系,且都表现出旱季高,雨季低的特点.表明宝晶宫3个滴水点的Mg/Ca、Sr/Ca很可能受到降水量、岩溶水来源、上覆土壤的淋滤作用以及碳酸盐先期沉积作用等因素共同影响,并能较好地反映该地区的干湿变化.

Geochemical dynamics of cave water were monitored to unveil its seasonal variation and controlling factors from December2011 to May 2013 in Baojinggong cave,north of Guangdong Province. Concentrations of elements such as Ba,Sr,Ca and Mg of three drips in the cave were analyzed. The results showed that： 1 All these elements of three drips displayed significant seasonal variations,but the trends of seasonal variation of different elements or different drips were not the same,which reflected that each element in different drips might be controlled by different effects; 2The low element contents of Drip1 and Drip2 during the heavy rainfall month showed that heavy rainfall could dilute the concentrations of elements; 3Mg/Ca had a positive relationship with Sr/Ca ratio in three drips,and was higher in dry season and lower in rainy season. It implied that the two proxies might be mainly controlled by precipitation,karst water source,leaching effect and prior calcite precipitation（ PCP）,and reflected the climate change.