Stable Carbon Isotope Variations in Cave Percolation Waters and their Implications in Four Caves of Guizhou, China  

作　　者：LUO Weijun WANG Shijie XIE Xingneng ZHOU Yunchao LI Tingyu 

机构地区：[1]State Key Laboratory of Environmental Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences [2]Puding Karst Ecosystem Research Station, Chinese Academy of Sciences

出　　处：《Acta Geologica Sinica(English Edition)》2013年第5期1396-1411,共16页地质学报（英文版）

基　　金：funded by National Key Basic Research Development Program (Grant No. 2013CB956700);Orientation Project of Knowledge Innovation Program of Chinese Academy of Sciences (Grant No. kzcx2-yw-306);National Natural Science Foundation of China (Grant Nos. 41003054 and 90202003)

摘　　要：Monitoring and sampling of main plants, soil CO2, soil water, bedrock, spring water, drip water and its corresponding speleothem were performed at four cave systems of Guizhou, Southwest China, from April 2003 to May 2004, in order to understand stable carbon isotope ratios variations of dissolved inorganic Carbon （DIC） in cave percolation waters （δ13CDIC） and their implications for paleoclimate. Stable carbon isotopic compositions and ions （Ca, Mg, Sr, SO4, CI etc.） were measured for all samples. The results indicate that there are significant differences among the δ13CDIC values from inter-cave, even inter-drip of intra-cave in the four caves. The δ13CDIC values from the Liangfeng Cave （LFC） is lightest among the four caves, where vegetation type overlying the cave is primary forest dominated by tall trees with lighter average δ13C value （-29.9‰）. And there are remarkable differences in δ13CDIC values of different drip waters in the Qixing Cave （QXC） and Jiangjun Cave （JJC）, up to 6.9‰ and 7.8‰, respectively. Further analyses show that the δ13CDIC values in cave drip waters are not only controlled by vegetation biomass overlying the cave, but also hydro-geochemical processes. Therefore, accurate interpreting of δ13C recorded in speleothems cannot be guaranteed if these effects of the above mentioned factors are not taken into consideration.Monitoring and sampling of main plants, soil CO2, soil water, bedrock, spring water, drip water and its corresponding speleothem were performed at four cave systems of Guizhou, Southwest China, from April 2003 to May 2004, in order to understand stable carbon isotope ratios variations of dissolved inorganic Carbon （DIC） in cave percolation waters （δ13CDIC） and their implications for paleoclimate. Stable carbon isotopic compositions and ions （Ca, Mg, Sr, SO4, CI etc.） were measured for all samples. The results indicate that there are significant differences among the δ13CDIC values from inter-cave, even inter-drip of intra-cave in the four caves. The δ13CDIC values from the Liangfeng Cave （LFC） is lightest among the four caves, where vegetation type overlying the cave is primary forest dominated by tall trees with lighter average δ13C value （-29.9‰）. And there are remarkable differences in δ13CDIC values of different drip waters in the Qixing Cave （QXC） and Jiangjun Cave （JJC）, up to 6.9‰ and 7.8‰, respectively. Further analyses show that the δ13CDIC values in cave drip waters are not only controlled by vegetation biomass overlying the cave, but also hydro-geochemical processes. Therefore, accurate interpreting of δ13C recorded in speleothems cannot be guaranteed if these effects of the above mentioned factors are not taken into consideration.

关 键 词：cave drip water stable carbon isotope biomass hydro-geochemistry SPELEOTHEM 

分 类 号：P641.3[天文地球—地质矿产勘探]