Ecological observations of pelagic bacterial and archaeal communities in the Atlantic-Arctic boundary zone

• Main Author: Fadeev, Eduard
• Other Authors: Sher, Daniel, Boetius, Antje, Hinrichs, Kai-Uwe
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Universität Bremen 2018
• Subjects: microbial communities; Arctic Ocean; FRAM; Fram Strait; bacterioplankton; 570; 570 Life sciences; biology; ddc:570; Arctic; Atlantic Arctic; Atlantic-Arctic; Climate change; Sea ice
• Online Access: https://media.suub.uni-bremen.de/handle/elib/1567; https://nbn-resolving.org/urn:nbn:de:gbv:46-00107081-11

The global climate change has an unprecedented impact on the Arctic Ocean, resulting in warming of the Arctic surface air at much faster rates than the global average. The warming temperatures lead to constantly declining Arctic sea ice cover, which reached in September 2018 the sixth lowest summertime minimum extent in the satellite record (since the late 1970s). Shrinking sea ice has a strong impact on the entire Arctic marine ecosystem, through alterations of the primary production, grazers communities, and subsequently the biological carbon pump. Current predictions of entirely sea-ice free summers in the Arctic Ocean already in the second half of this century urges the need to understand the ongoing oceanographic and biological processes in order to predict how the Arctic ecosystem will respond to further environmental changes. The differentiation between natural temporal ecosystem variability and anthropogenically-induced impact of the climate change requires long-term observations. The Ocean Observing System FRAM (FRontiers in Arctic marine Monitoring), which was established in 2014, is an Arctic long-term observatory for investigating the impact of changing ocean properties and sea ice conditions of the Arctic Ocean on its marine ecosystem. The starting point for the FRAM project was the already existing long-term observatory HAUSGARTEN, situated in the main gateway between the Arctic and the Atlantic Oceans - the Fram Strait. To date, despite their importance for the biogeochemical cycling, very little is known regarding the diversity and function of microbial communities in the Arctic Ocean in general, and specifically in the Fram Strait. In the framework of FRAM, a Molecular Observatory was established, for conducting standardized molecular-based high-resolution observations of the Arctic microbial communities. This thesis was conducted as part of the FRAM Molecular Observatory, and as part of the establishment process of the observatory it contributes to the methodological and procedural ...