| Secondary cave sediments had become an important carrier of the records, which show the ancient climate change of the karsts area, especially reflected in the high-resolution,short-time scale studies. Using the stable carbon and oxygen in the secondary cave sediments to reconstruct the ancient climate, and using high-precision U/Th dating techniques on a series of comparative study of abrupt climate change events is the focus of today's ancient climate research. However, in the use of secondary cave sediments in ancient climate reconstruction process, there are some study notes that its records are inconsistent with the ancient climate change, the study of the cave drips help us to accurately interpret the cave sediments' ancient climate information.This article choose the Furong cave in Chongqing Wulong as the study object, select drip water in two place(1#,3#),pool water in two place(2#,4#)inside the cave,and the water of the spring 6 # outside the cave for three hydrologic years'regular monitoring, in order to obtain their ionic and elemental geochemistry.monitoring indicators include the peak springs, cave drip water and pool water drip rate (just dripping),conductivity, pH, temperature, and the ionic concentration of Ca2+ Mg2+,K+,Na+,Sr2+,Ba2+,SO42-,HCO3-,Cl- and so on. At the same time, there is also a long-term dynamic monitoring about the environmental indicators(such as temperature, humidity, concentration of CO2, etc.) inside the cave, the environmental indicators(such as vegetation, soil, litho logy, etc.)of the peak outside the cave.Through this work, combined with instrumental data measured by the local weather station in Furong cave, mainly got the following preliminary findings:(1)Through monitoring the geochemistry and water chemistry indicators about dripping water, pool water and spring water from Mar.2006 to Feb.2009, combined with the local instrumental data,preliminary considered that the concentration and the ratio of the Sr2+,Ca2+,Mg2+in the cave drip water not only depends on environment precipitation and temperature changes, but also by the effects of changes in hydro-geological conditions.(2) The changing range and mean of the concentration of Ca2+,Sr2+,Mg2+,SO42-,and Cl" in cave drip water and pool water are quiet similar. Spring water outside the cave are more influenced by the external environment, changes in the complex. The study area of karst water in the study area achieved a good homogenization effect, before it moving on the top of the cave and coming into cave drip water. The average concentration of the Ca2+ in the 6 # spring water on the hill which outside the Furong cave is 45.81 mg/L, the average concentration of the Ca2+ in the 1#,3# cave drip water increased to 64.59 mg/L,Ca2+ deposited in the 2# and 4# pool water, its concentration dropped to 24.74 mg/L, declined by about 61.7%. The concentration changes of Mg2+ and Sr2+ in the spring water,drip water and pool water is basically same as the Ca2+, The concentration of Cl" changes a lesser extent in variety of waters, with an average concentration is 1.72±0.2 mg/L.(3) The contacting time between karst water and bedrock as well as prior calcite precipitation play an important role in the change of elements and ions. After the drought in July and August 2006, the concentrations of the SO42- and Cl- in the cave drip water and pool water respectively reached the valley in February 2007, at the same time the concentration of the Ca2+ also reached the minimums value, while the Mg/Ca and Sr/Ca reached the peak value. These indicators common change is a good reflection of the drought in the summer of 2006, showing that the chemical characteristics of the water in the Furong cave is sensitive to drought events. During the one to two month after the flooding in the summer of 2007, the concentrations of SO42" and Cl- went up first and then decreased, the concentration of Ca2+ has been declining, Mg/Ca and Sr/Ca also appeared corresponding fluctuations, simultaneous changes in these index are effected by the leaching of soil,bedrock dissolution and strong dilution.The pre-deposition of the Ca2+ during the dry season, the bedrock dissolution during the rainy season and the Rainwater dilution dominant the change of the Mg/Ca and Sr/Ca in the karst water, these index can response to the extreme climate events, such as drought and flood. However, the non-contemporary change between the ion concentrations and element ratios and local precipitation show that the residence time of water cycle in Furong cave karst system needs further study.(4) Through the correlation analysis of the Ca2+,Mg/Ca and Sr/Ca in the five sampling sites showed that, although the overlying rock in the Furong cave is a few hundred meters thick, however, during the migration process of karst water, the concentration of Mg2+ and Sr2+ showed an anti-related changes, the corrosion and sedimentation of Ca2+ is according to an approximate index change, with a certain regularity.
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