oa Microbial Life in the Hyrothermal Systems of the Valley of Geysers, Kamchatka Peninsula, Far Russian East

The valley of Geysers is an active hydrothermal area on the Kamchatka Peninsula in the Far Russian East characterized by many hot springs, steam vents and geysers and thus forms a multi-habitat environment for the indigenous microbial communities. In this study, we aim to investigate, compare and monitor the spatial changes of the microbial communities under the different habitat conditions in the valley by examining hot water pools and a drainage transect from a geyser to the local river. As tools we use a microbial biomarker lipid approach and compared the data to 16S rRNA gene profiling and hydro- and geochemical background data. The results show that the multi-habitat environment of the valley hosts a diverse bacterial and archaeal community, whose abundance, composition and spatial distribution is largely determined by the local environmental conditions. Although Archaea and Bacteria are present at all sites their relative proportions change with the extreme temperature fluctuations between the locations. Archaea are more prominent in hot water environments, while Bacteria, also abundant at the hot water sites, show their highest amount at the temperate sites and a clear adaptation of their taxonomic composition to the ambient temperature conditions.