Seasonal variations in trace elements and influencing factors in drip water from Kaiyuan Cave, Shandong Province

Drip water samples for 15 months were collected from the Kaiyuan Cave, Zibo City of Shandong Province, a cave located in a semi-humid monsoon climatic zone in coastal North China. Geochemical information suggests that: (1) the variations in dripping rates respond rapidly to the atmospheric precipitation outside the cave. (2) Although the Ca²⁺, Mg²⁺, Sr²⁺ and Ba²⁺ concentrations display significant seasonal variations, their behaviors and influencing mechanisms are rather different. (3) The Sr/Ca and Ba/Ca ratios of the drip water may respond to certain degree to the atmospheric precipitation outside of the cave, and, especially, the Mg/Ca, Sr/Ca and Mg/Sr ratios may well indicate heavy rainfall. However, the variations in Mg/Sr in the drip water do not respond obviously to surface air temperature.