Modern benthic diatom taxocenes of loose grounds of the coast of the Severnaya Zemlya archipelago and adjacent sea areas

Modern taxocenes of benthic diatoms of coastal aquatic habitats of the Severnaya Zemlya archipelago were studied for the first time based on the materials of the expedition in summer 2019. The following habitats were studied: sublittoral, littoral, as well as semi-enclosed coastal water bodies. In the entire set of communities, a total of 180 species and subspecies (IST) of diatoms were noted. The local α-diversity of communities in the sublittoral was 6–26 species and IST (on average – 14.8), and for coastal locations, including the littoral – 12–51 species and IST (on average – 33). The floristic groups and coenotic groups of diatoms have been identified for sublittoral and coastal habitats. Significant differences were noted both among coastal taxocenes (average similarity of 23.41% in species composition and 9.78% in structure) and among sublittoral communities (19.51% and 34.54%, respectively). The entire spectrum of the noted on permanent slides species are photodocumented.