南岭东部水源洞过去700年石笋氧同位素变化与气候意义

δ^(18)O record of a 700-years-old speleothem from the Shuiyuan Cave in eastern Nanling Mountain and its paleoclimatic implications

亚洲季风区内石笋氧同位素组成(δ18O)的气候环境意义解读近年来在国内外引起了广泛争议。通过比较近期石笋δ18O记录与历史文献记载的气候变化信息,可以为解决这一问题提供一些参考信息。本文高分辨率重建了南岭东部石笋δ18O记录。该记录变化趋势与历史文献记载的我国南方地区小冰期以来旱涝灾害频率变化趋势基本一致,说明该石笋δ18O记录变化可能与夏季风强度和季风降水变化密切相关。根据该记录,对南岭东部地区最近700年以来的夏季风变化特征进行了分析。

The focus of most paleoclimate reconstructions has been put on speleothem δ18O variability while the paleoclimatic and paleoenvironmental implications of δ18O have many controversies. The contrast between the recent stalagmite δ18O record and the climate change message recorded in the historical document can help to solve this problem. The history of high-resolution summer monsoon variations during the past 700 years was reconstructed by means of precise 230Th dating and the high-resolution oxygen isotopic （δ18O） analysis of SYD-6 stalagmite from the Shuiyuan Cave in eastern Nanling Mountain, China. It is found that the variation trend ofδ18O records is consistent with the change frequencies of drought and flood disasters in the southern areas of China as recorded by the historical document since the Little Ice Age, indicating the δ18O record of SYD-6 stalagmite may be closely related to the intensity of summer monsoon and monsoon precipitation. According to the record, we analyzed the summer monsoon variation in eastern Nanling during the past 700 years.