【摘要】 结合长江下游沿江地区埋藏古树和泥炭形成时间,以及南京浦口林峰桥中晚全新世地层的沉积相特征和地球环境化学分析,江苏南部句容宝华山麓距今5700年前后洪—坡积相地层特征、剖面沉积物中孢粉—气候转换曲线反映:距今5700年前后本区曾经发生过降温干燥事件,宝华山地区当时最低年均温为12.56℃,最低年均降水量为716.40mm。林峰桥剖面对应层位淤泥质沉积物中黏土含量及铁离子含量的异常变化验证了该事件的存在。同时研究也表明,此冷干事件不仅是区域古气候异常变化的反映,还具有全球气候变化的响应特征。更多还原

【Abstract】 Integrative study of buried peat and fossil trees in the lower reaches of the Yangtze River,analysis of sedimentary characteristics and environmental geochemistry of the middle and late Holocene strata in the Pukou and Linfengqiao areas in Nanjing,and research on sedimentary facies and pollen-spore climate curves around 5 700aBP in the Baohua Mountain area near Jurong of southern Jiangsu indicate that a dry-cold event occurred in this area around 5 700aBP.During this dry-cold interval,the lowest average annual temperature in the Baohua Mountain area was 12.56 ℃,and the lowest average annual precipitation was 716.40 mm.This event can also be verified by the abnormal variations in the content of clay and iron concentrations in the corresponding layers of the Linfengqiao profile,which is not only an abnormal reflection on regional palaeoclimate,but also shows the responsive characteristics of global change.更多还原