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Aim: Assess the spatial and temporal turnover of bentho‐demersal marine fauna by integrating ecological metrics at the community and food web levels and evaluate their main environmental and anthropogenic drivers. Location: Barents Sea. Method: We analysed data of benthic and bentho‐pelagic fish and megabenthic invertebrates caught in the Barents Sea ecosystem survey in August–September 2009–2017 to characterize the spatial and temporal variability of bentho‐demersal communities and food webs. We used a trait dataset and highly resolved bentho‐demersal food web to calculate community and food web metrics in space and time. We spatially clustered the community and food web based on their properties using archetypal analysis and investigated their co‐variation with environmental and fishing pressure using (hierarchical) redundancy analysis. Result: The community and food web metrics partitioned the Barents Sea into four sub‐regions where different pressures act on the bentho‐demersal fauna, such as sea ice loss and fisheries. Multiple community metrics (e.g. mean body length and trophic level) varied along an environmental gradient of annual mean sea bottom temperature, trawling intensity and ice‐cover, whereas multiple food web metrics (e.g. nestedness and connectance) varied along an environmental gradient of depth and sediment composition. Communities had higher biomass‐weighted variability in body size and omnivory values in areas where the Atlantic and Arctic water masses mix. Several food web and community metrics co‐varied (e.g. food chain length and mean trophic level). We found no clear temporal trends in the ecological metrics in any of the four sub‐regions, but the metrics had large inter‐annual variability with some local minima or maxima coinciding with high sea temperature and ice‐cover anomalies. Conclusion: Analyses at the community and food web level are seldom integrated in ecological studies, while this integration gives complementary information to assess patterns and drivers of ecosystem state and to better prioritize conservation efforts. [ABSTRACT FROM AUTHOR]

The Arctic is of special importance to the world, and it is changing rapidly. Uncovering the relationship between drivers of change and biological responses in the Barents Sea is therefore crucial for understanding the potential effects of climate change on the ecosystem in general and on commercially important species in particular. This thematic review provides an overview of the discussions related to long- and short-term variations in climate in the Barents Sea, what these physical changes really are, and how they may develop in the future. Furthermore, questions related to how these predicted climate-driven physical changes may alter ecosystems and the implications and future challenges that this represents for the management of resources in the area are raised. There is no doubt that to better understand the structure and function of an ecosystem, as well as to investigate the possible effects of climate changes, there is a need for thorough monitoring and data collection. The Barents Sea Ecosystem Survey (BESS) is used in several of the studies highlighted in this review. Therefore, we can provide a detailed description of the BESS and relate BESS research activities to other research initiatives in a thematic context. [ABSTRACT FROM AUTHOR]