鸡冠洞洞穴滴水和现代沉积物δ18O、δ13C对极端秋雨的响应  

The response of cave drip water and modern calcite deposition δ18O and δ13C in Jiguan cave,Henan to extreme autumn rain

作　　者：贾亦真 杨琰[2,3] 叶枝茂 田宁 许彦智[4] JIA Yizhen;YANG Yan;YE Zhimao;TIAN Ning;XU Yanzhi(Luoyang Vocational and Technical College,Luoyang 471500,China;Chongqing Key Laboratory of Karst Environment,School of Geographical Sciences,Southwest University,Chongqing 400715,China;Chongqing Jinfo Mountain Karst Ecosystem National Field Scientific Observation and Research Station,Chongqing 400715,China;Henan Jiguan Cave Tourism Development Limited,Luoyang 471500,China)

机构地区：[1]洛阳职业技术学院,洛阳471500 [2]岩溶环境重庆市重点实验室/西南大学地理科学学院,重庆400715 [3]重庆金佛山喀斯特生态系统国家野外科学观测研究站,重庆400715 [4]河南省鸡冠洞旅游发展有限公司,洛阳471500

出　　处：《第四纪研究》2025年第1期191-202,共12页Quaternary Sciences

基　　金：国家自然科学基金项目(批准号:42277048、41877450和41672160)资助。

摘　　要：华西秋雨是我国雨季的重要降雨过程之一,但是目前关于洞穴滴水和沉积物的δ18O、δ13C对华西秋雨的响应过程和机制的认识还不够深入。本研究通过对河南省栾川县西部鸡冠洞的连续12年的监测,结合2021年极端秋雨期间高分辨监测记录,分析洞穴水化学特征、大气环流和华西秋雨的发生情况,探究大气降水、洞穴滴水、沉积物δ18O、δ13C对华西秋雨的响应机制,研究发现:1)年际尺度上,研究区大气降水、洞穴滴水、沉积物δ18O、δ13C在秋雨年(2011年、 2017年、 2021年)9~10月偏负,非秋雨年偏正。大气降水δ18O主要受环流效应的影响,秋雨年来自热带印度洋的远源水汽增加,降水δ18O偏负。洞穴滴水和现代沉积物δ18O可以很好的继承大气降水δ18O蕴含的大气环流信号;洞穴滴水和沉积物的δ13C主要受控于大气环流状况调控的研究区降水量的变化。2)2021年的极端秋雨期间,研究区的降水事件与西太平洋副热带高压(西太副高)的发展密切相关。鸡冠洞滴水的δ18O、δ13C对大气降水的响应均存在滞后。鸡冠洞大气降水δ18O的变化可以响应水汽源的变化并且被记录在洞穴滴水和洞穴沉积物中,包含夏季风降水向华西秋雨的转变过程;洞穴滴水的δ13C变化受研究区降水量的变化影响。The processes and mechanisms of cave drip water and modern calcite deposition response to the Autumn Rain in Western China(ARWC)are still poorly understood.Hence,A 12-year(from September 2009 to December 2021)continuous monitoring process was carried out at Jiguan cave.2 cave drip sites(LYXS and TGBD)in Jiguan cave were monitored every 2 months,and 1 month in the rainy season.The monitoring elements include temperature,precipitation,hydrogen and oxygen isotopic compositions of the meteoric precipitation,oxygen and carbon isotopic compositions of cave drip water and modern calcite deposition,and carbon dioxide in overlying cave soil,etc.Jiguan cave(33°46'N,111°34'E;900 m a.s.l.at the entrance)is located on the north slope of the Funiu Mountains,about 4 km west of Luanchuan County,Luoyang City,Henan Province,Central China.The overlying bedrock mainly consists of Sinian chloritized marble with a thickness of 30~40 m.The mean annual precipitation and temperature are 846.4 mm and 12.4℃(1957~2022).This area will be significantly impacted when the ARWC is strong.Studies have shown that:(1)The δ18O of meteoric precipitation in Jiguan cave was-8.88‰and-6.57‰,and the precipitation amount was 187.9 mm and 72.8 mm in September to October of the autumn rainy year(2011/2017/2021)and non-autumn rainy year(years other than 2011/2017/2021 during the period of 2009 to 2021),respectively.The δ18O and the δ13C of the cave drip water and the modern calcite deposition were relatively negative from September to October in autumn rainy years(the mean values of δ18 O and δ13C of drip water were-10.21‰ and-12.32‰,respectively;and the mean values of δ18O and δ13C of modern calcite deposition were-10.13‰ and-10.22‰,respectively),whereas those from September to October in non-autumn rainy years were relatively positive(the mean values of δ18O and δ13C of drip water were-8.95‰and-11.61‰,respectively;the mean values of δ18O andδ13C of modern calcite deposition were-9.33‰and-10.04‰,respectively).The δ18O can

关 键 词：鸡冠洞 氧同位素 碳同位素 华西秋雨 大气环流 

分 类 号：P641.3[天文地球—地质矿产勘探]