Ecological Status of Romanian Black Sea Waters according to the Planktonic Communities

This paper reports Romanian Black Sea waters’ plankton diversity and abundance for three consecutive years (2015-2017). In these years, biodiversity has varied significantly in a seasonal aspect. Thus, we identified 199 species of phytoplankters, 25 microzooplankters, 23 mesozooplankters, and 3 gelatinous zooplankters. We also presentetd data on the microzooplankton community (tintinnids), two decades after being completely neglected in the monitoring of Romanian waters. The plankton diversity and abundance are crucial issues for the ecological status within Marine Strategy Framework Directive’s (MSFD) descriptors and indicators. The ecological status was evaluated for cold and warm seasons. As a result, all water bodies from the Romanian littoral were in "good ecological status" (GES), according to phytoplankton and mesozooplankton status. Regarding coastal waters, the phytoplankton biomass exceeded the target value, defining this water body as "non-GES".