Investigation of microbial ecosystems and their turnover processes in the sediments of the saline, alkaline Lake Van as part of the ICDP Drilling Project - PaleoVan -

在国际地球物理中心钻探项目“PaleoVan”的框架内，将从盐碱湖(土耳其)回收长沉积岩芯。拟议项目的目标是描述凡湖沉积物中的微生物过程、细胞丰度和主要系统发育类群的分布。该项目的一部分将致力于确定和量化沉淀柱中的周转过程，另一部分将侧重于微生物的空间变异性，并着眼于不同的微生境，例如火山灰层周围的单层和沉积界面。对于周转速率的测量，将使用直接放射性示踪实验和基于孔隙水中溶解化合物的浓度梯度的周转过程的数值模拟，以获得过程的总速率和净速率。样品的微生物学特征将通过清点微生物细胞总丰度和对主要生物群(例如细菌、古生菌、硫酸盐还原菌、产甲烷菌、ANME等)进行量化来完成。这些数据将使人们对碱性沉积物中的基本过程有一个基本的了解，这种环境到目前为止还没有得到更详细的研究。

Within the framework of the ICDP drilling Project „PaleoVan“ long sediment cores from saline, alkaline Lake Van (Turkey) will be retrieved. The goals of the proposed project are the characterization of the microbial processes, cell abundance and distribution of the major phylogenetic groups in the sediments of Lake Van. One part of the project will be devoted to the identification and quantification of the turnover processes in the sediment column, the other part will focus on the spatial variability of microbes and look at the different microhabitats, e.g single laminae and sedimentary interfaces around volcanic ash layers. For turnover rate measurements, both direct radiotracer experiments and numerical modeling of turnover processes based on concentration gradients of dissolved compounds in the porewater will be used in order to obtain the gross and the net rate of a process. The microbiological characterization of the samples will be done by enumeration of the total microbial cell abundance and the quantification of the dominant groups of organisms (e.g. Bacteria, Archaea, Sulfate reducers, methanogens, ANME, etc.). The data will provide a basic understanding of the fundamental processes in alkaline sediments, an environment that has so far not been studied in greater detail.