RESEARCH ON THE PHYTOPLANKTON STRUCTURE FROM ROSCI0066 DANUBE DELTA-MARINE AREA SITE IN VERNAL SEASON 2012.

This study represents a step in a comprehensive research study of specific aquatic flora and fauna for ROSCI0066 Danube Delta-Marine Area site developed over several years. The final result of the research will be the development of a plan of management measures for biodiversity conservation in this area. The phytoplankton is a fundamental link in the trophic chain and is one of the indicators to assess the status aquatic ecosystem. To assess the qualitative and quantitative structure of Phytoplankton in vernal season 2012 has been used samples collected from marine area with plastic water sampler (Niskin type). The qualitative structure of phytoplankton was characterized by the presence of 41 species belonging to 7 algal taxonomic groups: Bacillariophyta, Dinoflagellata, Chlorophyta, Cyanobacteria, Chrysophyta, Euglenophyta and Cryptophyta. The diatoms have dominated the number of qualitative structure of phytoplankton species in most study areas, their share ranging between 18% and 53%. The dinoflagellates were the second group that diversity, the proportion ranging from 6% and 44%. Marine waters from ROSCI0066 site, in vernal season 2012, were characterized by values of densities of 48 - 4300⋅10³ cells-1 and 0.04 to 1.62 g⋅m-3for biomasses. The diatoms have dominated for more than 72% in density and 43% in biomass. In conclusion the phytoplankton is not presented as an integral whole viable, but is rather the appearance of a heterogeneous floating tanatocenosis. It seems that in the site ROSCI0066 Danube Delta-Marine Area not exists a specific phytoplankton; the mixed waters from here are always pushed by winds and currents in all directions, especially towards South. [ABSTRACT FROM AUTHOR]