Climate change threatens shallow Arctic macrofaunal blue carbon stocks

This study examines mollusk communities in shallow (< 150 m) and deep (> 200 m) zones of Arctic, sub-Arctic, and temperate fjords to assess macrofaunal blue carbon storage under climate change. Biomass and trait-based analyses show that shallow Arctic habitats support long-lived, large suspension feeders with high carbon storage potential. In contrast, warmer regions host smaller, short-lived taxa, indicating reduced carbon storage and altered climate feedbacks. These findings underscore the vulnerability of existing zoobenthic carbon stocks and highlight the need to expand research to other taxa and full benthic communities across the European Arctic.