Molecular identification of eukaryotic communities from polar glacial ice cores BIOICE-UC

冰川冰和永久冻土的特殊物理和化学条件使单细胞生物得以长期保存。众所周知，这些环境作为一种独特的基质，提供了单细胞生物的长期记录。被困在冰芯中的生物可以提供有关古代生物多样性的信息，在某些情况下甚至可以提供关于进化过程的信息。虽然在估计有75万年历史的冰上记录了细菌，但关于原生生物的信息很少。到目前为止，已经在超过10万年的冰芯中发现了绿藻和真菌，这表明在旧冰芯中可以识别出原生生物。异养原生生物是所有陆地和水生生态系统的主要组成部分，构成了真核生物通过大气运输的休眠阶段的主要部分，这得到了我们在本项目中的初步研究的支持。该项目延长的主要目标是使用更有效的454下一代测序来检测和表征古代异养真核生物。该项目与AWI合作，致力于冰川学和微生物学，旨在为在气候变化背景下理解古代生物多样性贡献新的想法。由于研究多样性模式所需的大量冰，我们现在也想包括永久冻土样本。根据我们的前期工作，异养纳米原生生物由于其特殊的生态需求，应该成为环境条件变化的潜在指示生物。与我们的项目合作伙伴(由Töbe等人，Bündelantrag BIOICE提出)，我们希望创建大量关于古代原生生物出现的新信息，并创建一个结合原核生物和真核生物生物多样性模式的数据集，这可能在未来作为新的替代方案。

The special physical and chemical conditions of glacial ice and permafrost allow the longterm preservation of unicellular organisms. These environments are known to serve as a unique matrix offering a long-term record of unicellular organisms. Organisms trapped in ice cores can provide information on ancient biodiversity and in some cases even on evolutionary processes. While bacteria have been recorded from ice estimated to be as old as 750,000 years, there is only very little information on protists. Up to now, green algae and fungi have been reported from ice cores older than 100,000 years indicating that protists can be identified in old cores. Heterotrophic protists are the major components of all terrestrial and aquatic ecosystems and form the major part of dormant stages of eukaryotes transported via the atmosphere, this is supported by our preliminary studies within the current project. The major objective of the prolongation of the project is to detect and characterize ancient heterotrophic eukaryotes using the much more efficient 454 next generation sequencing. In cooperation with the AWI, working on glaciology and microbiology, the project is aimed to contribute new ideas to the understanding of ancient biodiversity in the context of climatic changes. Due to large amounts of ice necessary to study diversity patterns we like to include now also permafrost samples. According to our pre-work, heterotrophic nanoprotists, due to their specific ecological requirements, should serve as potential indicator organisms for changes in environmental conditions. Together with our project partners (proposal by Töbe et al., Bündelantrag BIOICE), we hope to create a lot of new information of ancient occurrences of protists and to create a data set combining prokaryote and eukaryote biodiversity patterns which may serve as a new proxy in future.