黔西南高分辨率泥炭记录的末次冰消期以来植被演替及其对气候变化的响应

贵州位于亚洲季风影响的核心区，生态环境脆弱，是开展季风演化和植被响应研究的理想区域。末次冰消期以来气候快速变化对区域植被生态系统产生了重大的影响。贵州地区末次冰消期以来详细的古植被研究较薄弱，植被对气候变化的响应仍不清楚。本项目拟选取黔西南较为罕见的能覆盖末次冰消期以来的泥炭钻孔岩心为主要研究对象，通过高分辨率年代学和代用指标分析，获得孢粉、腐殖化度、植物多样性等序列，结合表土孢粉资料，通过WAPLS等方法，定性及定量重建气候变化的历史和特征，恢复不同时期的植被及其演替过程，探讨黔西南植被对气候变化和突变性的响应。通过区域对比与分析，揭示西南喀斯特地区植被演替对气候变化的响应模式，重点解析植被对气候突变事件的敏感性及其变化内涵。本项目可为评估喀斯特地区未来的气候环境变化趋势及其对生态环境的影响提供理论基础和科学支撑。

Guizhou is located in the core area of the Asian monsoon and its ecological system is fragile due to the huge area of karst landform. Therefore, Guizhou can act as an ideal area for the study of the evolution of Asian monsoon and the response of vegetation dynamics to climate change. The period of last deglaciation is very suitable to test the effects of rapid climate change on vegetation. Sporopollen is usually considered as a direct indicator of paleovegetation. However, there is shortage of detailed long-term high-resolution sporepollen record and the discussion on the response of vegetation to climatic events is still poorly understood in Guizhou. The rare ca. 7 m thick peat sequence from the Xingyi peatland in the karst region of southwestern Guizhou provides a continuous sedimentation record spanning from the the last deglaciation to present. Based on closely spaced accelerator mass spectrometry (AMS) 14C dating, this proposal establishes a high-resolution geochronological framework since the last deglaciation. Based on the high-resolution sporepollen record, humification and other indicators obtained from Xingyi peat core, and the plant species diversity data sets in combination of other information, the evolution history of climate and its characteristics since the last deglaciation can be reconstructed. Based on sporepollen assemblages in surface soil samples from this study and the publications, the paleoclimatic parameters by multiple methods which includes weighted averaging partial least squares regression method (WAPLS), will be quantitatively reconstructed. The paleovegetation and its succession process in different periods will be also reconstructed. The response of paleovegetation to the paleoclimate conditions and its mutation will be explored. By the comparisons of regional climate and vegetation records, the general response patterns of vegetation succession to climate change in the southwestern karst region of China can be achieved. The sensitivity of vegetation and it corresponding variation forms to climate events then will be further analyzed. The proposal provides important valuable long-term perspectives and theoretical basis, scientific support for assessing the climatic variability and its impact on the ecological environment in the karst region.