蒙新高原湖泊表层沉积物花粉和盘星藻现代过程研究

蒙新高原横跨我国西风区和冬、夏季风区，是过去环境变化研究的敏感和重点地区。然而，该地区湖泊表层沉积物花粉和盘星藻现代过程研究不足，不能给植被和气候变化重建提供充足的现代过程依据，导致古环境重建存在不确定性。为此，本研究选择该地区湖泊表层沉积物花粉和盘星藻为研究对象，结合区域植被、气候、地貌、水文等环境因子，利用多元统计分析等方法，在区域尺度上研究湖泊中心表层沉积物花粉组合与植被和气候关系，构建现代花粉-气候定量关系，检验评估其可靠性和应用潜力；开展干旱区湖泊花粉来源与源区研究，揭示湖泊沉积物花粉空间代表性；开展1~2个封闭中小型湖泊花粉相对产量及源区研究，揭示花粉相对产量与植被关系；开展不同沉积环境下花粉保存研究，揭示湖泊沉积物花粉保存影响机制；研究湖泊表层沉积物盘星藻组合与水环境因子关系，揭示其环境指示意义。本研究有望为蒙新高原湖泊沉积物古环境重建解译提供依据。

The study on environmental and climatic implications of palaeo-environment proxies is important for Inner Mongolia and northern Xinjiang area, not only because that the study area is situated at the core area influenced by the Westerlies and Asian monsoon system, but also for that the poorly perspectives of environmental and climatic implications of pollen and Pediastrum. Here, we aim to explore the modern processes of pollen and Pediastrum to reveal their implications for palaeo-environment and palaeo-climate reconstruction. In regional scale, calibration set of modern pollen and climate based on lake surface sediment will be constructed and quantitative relationships between pollen and climate will be developed and tested. Furthermore, relative pollen productions (RPPs) will be studied based on the modern lake surface pollen assemblages and regional vegetation inventory for one or two closed lakes. Furthermore, pollen source area and transportation will be explored to reveal the geographic representation. In addition, pollen deposition and preservation will be explored. And, Pediastrum assemblage will be explored for lake surface sediment, and relation to hydro-environment variables will be revealed to provide basis for palaeo-environment reconstruction. In lake basin scale, spatial patterns of pollen assemblage and Pediastrum assemblage will be disclosed and associated dynamics will also be revealed, so that environmental and sedimentary implications could be disclosed.