哈萨克丘陵全新世气候变化的高分辨率重建

The Kazakhstan Hills are important both ecologically and climatologically. It is not only an important ecological transition where the Taiga forests in the north have interacted with the steppes in the south and also an important climatic conjunction where the North Atlantic climate systems from the west have interacted with the Pacific climate systems from the east. However, Kazakhstan Hills is a data-lacking area in terms of the Holocene climate reconstruction. To quantitatively depict the geographic consistency of the Holocene climate change over the interior part of Eurasian continent, this proposed project is designed to achieve following two objectives. First, to develop the needed quantitative relationships between bio-proxies (i.e., pollen, biomarker compositions (GDGTs)) and climatic parameters, this project plans to extensively and intensively collect and analyze surface samples (~100 samples for pollen analysis and ~250 samples for biomarker composition analysis) over a relative vast area (48-54ºN, 65-85ºE). Second, to establish four well-dated and high-resolution Holocene sequences in the Kazakhstan Hills and to quantitatively reconstruct the Holocene climate change in the Kazakhstan Hills by applying the newly-developed quantitative relationships between bio-parameters and climate parameters to these four newly-obtained sequences (~800 samples). And then we analyses the characteristics of spatial and temporal variability of Holocene climate changes and associated driving mechanism in the Kazakhstan Hills. In addition, the internet-accessible climate reanalysis data provide us a golden opportunity to calibrate the relationships between bio-parameters and climate parameters.

哈萨克丘陵具有生态学和气候学上的双重重要性：不仅是其北侧的西伯利亚针叶林和其南侧的温带草原之间的过渡带，也是来自西方的北大西洋气候系统与来自东方的太平洋气候系统的叠合区。但是，从全新世气候重建的角度看，哈萨克丘陵是一个资料匮乏的地带。为了定量地勾勒欧亚大陆内陆全新世气候变化的时空序列，本项目旨在实现以下两个目标：（1）建立哈萨克丘陵气候参数与生物指标（包括孢粉、生物标记化合物（GDGTs））之间的定量关系；（2）定量地建立高分辨率的全新世气候序列。为了实现目标（1），计划在哈萨克丘陵（48-54ºN，65-85ºE）野外采集和室内分析约100个孢粉样品（已有108个样品）和约250个生物标记化合物样品。为了实现目标（2），计划在哈萨克丘陵野外采集和室内分析4根全新世泥炭芯（约800个样品）。还有，网上可得的再分析气候资料给我们建立“气候参数与生物指标之间的关系”提供了方便。

本项目（高分辨率重建哈萨克丘陵全新世水文变化及气候驱动）基本完成了任务。第一，本项目分析了研究区80个表土孢粉样品和271个表土有机碳碳同位素样品，确定了研究区表土孢粉类型和碳同位素与气候因子的响应关系。第二，分析了哈萨克丘陵及其周边的Kayan、Kolbay、托勒海特、干海子、柴窝堡和巴音布鲁克泥炭序列，共获得了约50个碳14（AMS）年代，完成了约1100个孢粉样品鉴定和约300个样品的常规地球化学指标分析，重建了上述地区过去植被和气候变化历史。迄今为止发表了16篇SCI论文，还有4篇SCI正在发表中。