Environmental studies of the macrozoobenthos in the nearby coastal zone along the Bulgarian Black Sea coast

E. Petrova, S. Stoykov
Abstract. The interest in studies of the nearby coastal zone of the Black Sea is great because it is the most productive section of the basin. The variety of habitats, water aeration, good temperature and density of nutrients coming from the nearest land and littoral contribute to the development of intensive life in it. In this area there are representatives of almost all groups of benthic organisms with the exception of some deep species. At the same time proximity to the coast makes it the most polluted part of the sea. Following the EU requirements pollutants are greatly reduced, which affects favourably biodiversity in the Black Sea ecosystem. 77 taxa of macrozoobenthos species were established, divided into four main groups: Polychaeta, Mollusca, Crustacea and “Diversa”. The ecological status is calculated on the Index of species diversity (H’), marine biotic index (AMBI) and multivariate Marine Biotic Index (M-AMBI). The results of the studies of macrozoobenthos from north to south in the nearby coastal area tend to improve the ecological situation in comparison with previous periods.