Data from: Data-driven bioregionalization: A seascape-scale study of macrobenthic communities in the Eurasian Arctic

Aim: We conduct the first model-based assessment of the biogeographical subdivision of Eurasian Arctic seas to (1) delineate spatial distribution and boundaries of macrobenthic communities on a seascape level; (2) assess the significance of environmental drivers of macrobenthic community structures; (3) compare our modelling results to historical biogeographical classifications; and (4) couple the model to climate-change scenarios of environmental changes to project potential shifts in the distribution and composition of macrobenthic communities by 2100.

Location: Eurasian Arctic seas, in particular Barents, Kara, and Laptev Seas

Taxon: Macrobenthic fauna

Methods: We employed the Region of Common Profile (RCP) approach to assess the regionalization patterns of Eurasian Arctic seafloor communities.

Results: Four RCPs were identified based on the spatial distribution patterns of 169 macrobenthic species and a set of environmental factors, such as sediment composition, sea-ice concentration, depth of the euphotic zone, particulate organic carbon concentration at the ocean surface, as well as near-bottom water temperature and salinity. The identified regions are in strong agreement with previous classifications of macrobenthic communities. The projections are driven by climate-change scenario "Representative Concentration Pathway 6.0" suggested a general eastward shift of the RCPs over the 21st century, correlated to retreating sea-ice and increasing sea-bottom temperature.

Main conclusions: The RCP approach allowed us to identify seascape-scale distribution patterns of macrobenthic communities in Eurasian Arctic seas by simultaneously considering biotic and environmental data within one modelling step. This technique can represent biota and ecoregions in a probabilistic form together with assessment of uncertainties of the predictions, and assess the significance of a broad selection of environmental drivers. This first quantitative assessment of potential climate-driven changes in macrobenthic biodiversity will promote their inclusion in conservation measures.