Pliocene Arctic vegetation and its feedbacks with climate: combining Lake El´gygytgyn pollen data and vegetation modelling

拟议的调查将用于ICDP资助的位于西伯利亚东北部的El'gygytgyn钻井项目。主要包括对El´gygytgyn湖中部D1岩心上新世和早更新世部分的孢粉学分析，补充了俄罗斯和美国合作的孢粉学家在中新世和晚更新世岩心部分的研究。温暖的上新世被认为是未来全球变化的近似模拟。我们的目标是(A)利用基于化石花粉数据的逆植被模拟来量化过去的气候变化，从而得出未来北极可能进一步变暖的结论；(B)使用基于花粉的景观模型来量化树木类群的覆盖率，我们将根据植被-气候反馈机制对其进行解释；(C)推断过去的花粉库存和多样性及其随气候周期的变化，以了解现代北极植被的起源和来源。在我们的研究设计中，我们故意将现代和化石花粉研究以及基于代理和建模的方法结合在一起。在我们的项目中，我们将从古气候的角度来讨论有关当今和未来北极变暖及其对植被的反馈的有争议的问题。

The investigations proposed contribute to the ICDP funded „El'gygytgyn Drilling Project“ in northeastern Siberia. They mainly comprise palynological analysis of the Pliocene and Early Pleistocene part of core D1 from central Lake El´gygytgyn, thus complementing respective investigations in the Middle and Late Pleistocene core part by collaborating palynologists in Russia and the USA. The warm Pliocene epoch is considered to be a close analogue to future global change. We aim (A) to quantify past climate change using inverse vegetation modelling based on fossil pollen data to conclude about potential further warming of the future Arctic; (B) to quantify tree taxa coverages using pollen-based landscape modelling that we will interpret in terms of vegetation-climate feedback mechanisms; (C) to infer past pollen inventory and diversity and its changes with climate cyclicity to understand the origin and source of modern Arctic vegetation. We deliberately intertwined modern and fossil pollen studies as well as proxy-based and modelling approaches in our study design. With our project we will contribute a palaeoclimatic perspective to controversially discussed questions concerning present-day and future Arctic warming and its feedbacks with vegetation.