Zoobenthos biodiversity over the soft bottom in the Crimean coastal zone of the Black Sea

Data on the structure of the zoobenthos inhabiting the soft bottom of the shelf zone off the Crimean coast of the Black Sea are given. The samples were collected in the spring of 1999. At eleven stations, at depths from 22 to 142 m, 149 macrobenthic species were found. The parameters of the species diversity and the quantitative (abundance and biomass) development of the principal benthic groups (mollusks, annelids, crustaceans, miscellaneous, or other) dwelling in different areas were analyzed. In general, for the Crimean coast, annelids (75%) and mollusks (89%) are the leading benthic groups in terms of abundance and biomass, respectively. To estimate the benthos diversity, Shannon's, Simpson's, and Pielou's indices were used. For the first time, the presence of the bivalve mollusk Scapharca inaequivalvis was noted off the coast of the South Crimea (the Karadag and Alushta areas). The results obtained allow us to estimate the state of the bottom ecosystems dwelling in the Crimean coastal zone of the Black Sea as fairly satisfactory.