demersal fish assemblages and spatial diversity patterns in the arctic-atlantic transition zone in the barents sea底栖鱼组合和空间多样性的模式arctic-atlantic巴伦支海的过渡区.pdfVIP

Demersal Fish Assemblages and Spatial Diversity Patterns in the Arctic-Atlantic Transition Zone in the Barents Sea 1 ˚ 2 3 4 Edda Johannesen *, Age S. Høines , Andrey V. Dolgov , Maria Fossheim 1 Ecosystem Processes Research Group, Institute of Marine Research, Bergen, Norway, 2 Pelagic Fish Research Group, Institute of Marine Research, Bergen, Norway, 3 Laboratory of Trophology, Polar Research Institute of Marine Fisheries and Oceanography, Murmansk, Russia, 4 Ecosystem Processes Research Group, Institute of Marine Research, Tromsø, Norway Abstract Direct and indirect effects of global warming are expected to be pronounced and fast in the Arctic, impacting terrestrial, freshwater and marine ecosystems. The Barents Sea is a high latitude shelf Sea and a boundary area between arctic and boreal faunas. These faunas are likely to respond differently to changes in climate. In addition, the Barents Sea is highly impacted by fisheries and other human activities. This strong human presence places great demands on scientific investigation and advisory capacity. In order to identify basic community structures against which future climate related or other human induced changes could be evaluated, we analyzed species composition and diversity of demersal fish in the Barents Sea. We found six main assemblages that were separated along depth and temperature gradients. There are indications that climate driven changes have already taken place, since boreal species were found in large parts of the Barents Sea shelf, including also the northern Arctic area. When modelling diversity as a function o