为了研究洞穴滴水及其对应的现代沉积物氧同位素的变化特征和对外界气候环境的指示意义,文章对贵州纳朵洞洞外大气降水、洞穴池水、6处滴水点及其对应的现代沉积物氧同位素进行了近2年的监测.结果显示纳朵洞外大气降水和洞穴池水δ18 O值均呈现旱季偏重,雨季偏轻的季节特征,基本能反映洞穴所在区域的气候变化.而滴水沉积物δ18 O值和滴水δ18 O值自身存在协调同步的季节特征,但二者δ18 O值与大气降水δ18 O值却呈现反向的季节变化,这可能是区域地形、岩溶表层带的调节和大气环流共同作用的结果.%To explore the cave drip water and the variation characteristics of its corresponding oxygen iso-topes in modern deposits and their significance to the climatic environment,the atmospheric precipitation outside the Naduo cave in Guizhou,cave pool water,six drip points and their corresponding modern deposits oxygen stable isotopes have been monitored for the past 2 years.The results show that the δ18 O in atmos-pheric precipitation,drip water,and deposits of Naduo cave are generally lower than those in most other southern regions.However,the seasonal variation ofδ18 O from all three sources is significant.For example, theδ18 O in atmospheric precipitation outside Naduo cave and in cave pool water both have seasonal character-istics that are higher in the dry season and lower in the wet season,and can basically reflect the climate change in the area where the cave is located.Though theδ18 O in deposits and drip water have similar season-al variation,they show a very different pattern from theδ18 O in the atmospheric precipitation.This may be the result of the combination of regional topography,karst surface zone regulation,and atmospheric circula-tion.
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