статья в журнале

En

Marine Biological Journal

ISSN:24999768

2023

Kovalyova, I.V.¹

Finenko, Z.Z.¹

10.21072/mbj.2023.08.4.04

The spatial and temporal variability of phytoplankton biomass in the surface layer of the Black Sea during an 18-year period is analyzed, and the effect of the main currents in the sea on the spatial and temporal dynamics of phototrophic phytoplankton biomass is assessed. Regular long-term chlorophyll concentration data were used, obtained from satellite observations with SeaWiFS and MODIS-Aqua/Terra instruments in the Black Sea for 1998–2015. The role of macro- and microcirculations in the spatial and temporal variability of phytoplankton biomass is estimated. A gain in wind activity and a drop in water temperature from October to March, which lead to an increase in the depth of the mixed upper layer and the intensity of the main synoptic circulations, become a significant factor promoting winter–spring phytoplankton bloom. As revealed, a decrease in the mean water temperature in the cold season to +7…+8 °C, lasting for more than six weeks in the deep-water zone, leads to the intensive biomass development in spring. It was established that the mean phytoplankton biomass for 18 years in the western and eastern cyclonic cycles is (38.0 ± 17.8) and (37.7 ± 16.8) mg C·m-3, respectively, and in the Batumi anticyclone, (38.2 ± 18.0) mg C·m-3. As a rule, the Rim Current carries phytoplankton formed at the shelf zone along the coastline and almost does not mix with deep waters. In the cyclonic cycles, winter–spring phytoplankton bloom is observed on average for six weeks. Intensive bloom in the area of the flow of northwestern rivers, recorded in May–June, extends to the Bosporus, while in the cold season, it can penetrate into the deep-sea area in the form of micro-eddies. In winter and spring, the Sevastopol anticyclonic eddy stood out as a separate zone in terms of biomass development. The role of anthropogenic load is most significant in the coastal zone. However, the effect of coastal waters on the deep-sea area is possible in late autumn and winter. © The Author(s) 2023.

Black Sea, depth of the mixed layer, phytoplankton biomass, spatial variability of phytoplankton biomass, synoptic circulation, water temperature

2024-08-07 12:12:40