地理研究 ›› 2014, Vol. 33 ›› Issue (6): 1167-1177.doi: 10.11821/dlyj201406016

• 气候与环境变化 • 上一篇    下一篇

大九湖钻孔记录的神农架地区中更新世晚期以来的气候环境变化

郑秋凤, 张茂恒, 李吉均, 舒强, 陈晔, 萧家仪, 赵志军   

  1. 南京师范大学地理科学学院, 江苏省环境演变与生态建设重点实验室, 南京 210023
  • 收稿日期:2013-10-10 修回日期:2014-03-23 出版日期:2014-06-10 发布日期:2014-06-10
  • 通讯作者: 赵志军(1973-),男,副教授,从事地貌学与第四纪地质学研究。E-mail:zhao1029@gmail.com E-mail:zhao1029@gmail.com
  • 作者简介::郑秋凤(1987-),女,江苏常州人,博士研究生,从事气候变化研究。E-mail:zhengqf611@163.com
  • 基金资助:
    国家自然科学基金项目(40972112,41072127);江苏省高校优势学科建设项目

The climate and environment change of Shennongjia area recorded in the core of Dajiuhu Basin since the late Middle Pleistocene

ZHENG Qiufeng, ZHANG Maoheng, LI Jijun, SHU Qiang, CHEN Ye, XIAO Jiayi, ZHAO Zhijun   

  1. College of Geography Science, Nanjing Normal University, Key Laboratory of Environment al Evolution and Ecological Construct of Jiangsu Province, Nanjing 210023, China
  • Received:2013-10-10 Revised:2014-03-23 Online:2014-06-10 Published:2014-06-10

摘要: 运用孢粉浓缩物AMS 14C测年和氨基酸测年方法结合气候地层对比,建立神农架地区大九湖盆地DJH-2 孔的地层年代序列。依据孢粉分析结果并结合沉积环境,将大九湖盆地中更新世晚期以来的植被演替和古气候演化划分为六个阶段:① 275.0-188.0 ka,寒冷偏干,寒温带针叶林、高山草甸;② 245.0-188.0 ka,暖湿偏干,常绿、落叶阔叶混交林;③ 188.0-129.0 ka,冷干,寒温带针叶林为主,过渡为高山草甸为主;④ 129.0-71.8 ka,暖湿,暖温带落叶阔叶林;⑤71.8-15 ka,冷干,寒温带针叶林与高山草甸间隔发育,中间有喜暖种属增多的迹象;⑥ 15.0-1.0 ka,暖湿,亚热带常绿、落叶阔叶林。孢粉组合特征及单种属特征所显示的盆地气候变化反映了良好的全球冰期、间冰期气候旋回。孢粉浓度特征反映大九湖盆地气候变化受北半球高纬冰量与低纬太阳辐射的双重控制。

关键词: 神农架大九湖盆地, 中更新世晚期, 气候变化, 孢粉分析

Abstract: We have established the stratigraphic sequence of DJH-2 core, Dajiuhu Basin in Shennongjia Mountain. AMS dating and amino acid dating methods are applied to determine the age. Combined with climate stratigraphic correlation, the age of the core bottom is about 275. 8 ka. According to the results of pollen analysis and sedimentary lithology, we have divided the vegetation succession and paleoclimate evolution into six stages since the late Middle Pleistocene. Stage one (275.8-245.0 ka): It was cold and dry, and coniferous forests and alpine meadows developed. Stage two (245.0-188.0 ka): It covered with temperate evergreen and deciduous broad-leaved forests. And it was warmer than stage one. Stage three (188.0-129.0 ka): The paleoclimate condition was similar to stage one, and its major vegetation shifted from coniferous forests to mountain meadow. Stage four (129.0-71.8 ka): The paleoclimate was warm and humid. And it was suitable for temperate broadleaf forests. Stage five (71.8-15.0 ka): The middle pollen subzone had the most of pollen concentration. The pollen belt reflected unstable climate but totally cold and wet. Stage six (15.0-1.0 ka): It was warm and humid to fit for the subtropical evergreen and deciduous broad-leaved forests. In comparison with oxygen isotope sequences of stalagmites (Sanbao caves) in East Asia and marine sediments (SPECMAP), the results show that the past vegetation changes of Shennongjia area responded sensitively to the climate changes. The variation of palynological assemblages followed climate changes, especially some species. The change of rhythm was similar to the global glacial-interglacial climate cycle. The climate change was induced by the ice volume from the high latitudes of the northern hemisphere. And it was also affected by solar radiation at low latitudes. The two factors played an important part in pollen concentration variation.

Key words: Dajiuhu Basin of Shennongjia area, late Middle Pleistocene, climate change, pollen analysis