摘要
通过贵州草海南屯泥炭沉积中的腐殖化度、烧失量两个指标时间序列的综合分析，重建了草海地区自7.1cal.ka B.P.以来的古气候演变特征。结果表明，约7.1~4.5cal.ka B.P.期间，气候波动较为和缓，总体表现为由暖湿逐渐向干冷转变；4.5~2.4cal.ka B.P.期间，气候先出现了两次明显的波动下降，后来快速回升，波动较为剧烈；2.4cal.ka B.P.以后降水逐渐减少，气候总体干冷，但干湿波动频繁。通过区域对比发现，贵州草海地区反映的突变事件与红原、董哥洞、哈尼以及北大西洋地区古环境记录的气候突变事件有较好的对应；同时发现厄尔尼诺的活动强度与西南季风的强弱呈现明显的反相关关系，西南季风的气候波动很可能是ENSO事件驱动的结果，西南季风区受高纬驱动影响相对较小而受低纬驱动影响显著；另外，功率谱分析结果发现气候变化与太阳活动较为一致的周期有1108a、405a和205a，因此太阳活动是全新世西南季风波动主要的自然控制因子。研究结果表明太阳活动与低纬度因子（El Nino等）是中全新世以来西南地区气候变化的重要驱动力。
The Caohai peat is located in the eastern of Yungui Plateau, approximately between 26°44＇~27°01＇N, 104°00＇~104°30＇E, with an area of about 50km2. The Caohai is typically subtropical and subalpine area in our country, because of the double influence of the southwest monsoon and the East Asian monsoon. It is sensitive to the climate change, making it an ideal region for the climate change research of the southwest of China during the Holocene. A peat profile NT （26°52＇N, 104°15＇E; 2202m a.s.l., 339cm in depth）was digged in April, 2011, in Caohai, Weining County, Guizhou Province, located in the northeast of Caohai Basin, and 339 soil samples were collected from the bottom to the top of the profile at every 1cm.AMS 14C was dated by the residual seed extracted from peat samples. In this study, the climatic evolution since 7.1cal.ka B.P. in Caohai area was reconstructed by the records of humification and loss on ignite （LOI）of the NT profile.The results showed that the climatic evolution since 7.1cal.ka B.P. in Caohai area could be divided into three stages. The first stage was warm and wet during the period of 7.1~4.5cal.ka B.P., and the climate fluctuated gently. The second period, from 4.5cal.ka B.P. to 2.4cal.ka B.P., could be further divided into sub-stages：peat humification and ignition loss appeared two obvious drops since 4.5cal.ka B.P., the temperature began to bounce back after 3.8cal.ka B.P.. During the period of 3.1~2.4cal. kaB.P., it showed a warm-wet phase continuing about 700a. Since 2.4cal.ka B.P. the climate has been cold and dry than the the former two phases. The climatic evolution progress in the Caohai area is highly unstable and has undergone century-millennial scale through all three periods. There has been seven cold events that happened in about 6.5cal.ka B.P., 6.0cal.ka B.P., 5.0cal.ka B.P., 4.2cal.ka B.P., 3.8cal.ka B.P., 1.9cal.ka B.P. and 0.9cal.ka B.P. since the Middle Holocene. These evidently correspond with Hongyuan peat, Dongge cave stalagmite, Hani peat, and with deep-sea sediments in high latitude regions in the Northern Hemisphere. The above results show that the climatic change in the Caohai area since the Middle Holocene is consistent with the global climatic change.
Comparing the Caohai peat in transition zone with the Hongyuan peat in the southwest monsoon area and Hani peat in the East Asian monsoon region, the high latitude driving （North Atlantic Oscillation）and the low latitude driving （El Nino）in the eastern monsoon region were stronger than the southwest monsoon area, otherwise the southwest monsoon area was affected by the low latitude driving than the high latitude driving., and the Caohai peat in transition zone was driven by the high and the low latitude factor at moderate levels. Using the power spectrum analysis, the remarkable cycles of the climate variations is 1108a, 405a, and 205a, which correspond with the periodicity of the solar activities. Therefore, it reflects that the solar activity and El Ni？o are important driving forces to the climate change in the southwest monsoon area.
出处
《第四纪研究》
CAS
CSCD
北大核心
2017年第6期1357-1369,共13页
Quaternary Sciences
基金
国家自然科学基金项目（批准号：41571040和41271054）资助
关键词
草海泥炭
腐殖化度和烧失量
全新世
ENSO
太阳活动
peat of Caohai area, humification and loss on ignite （LOI） , Holocene, ENSO, solar activity
