Supervisors info:
Γενίτσαρης Σάββας, Επίκουρος Καθηγητής, Τμήμα Βιολογίας, ΕΚΠΑ
Summary:
This thesis focuses on the high-frequency monitoring of the composition and dynamics of unicellular eukaryotic planktonic communities in a coastal area of the Saronikos Gulf. The Saronikos Gulf is one of the most important yet heavily impacted marine areas of Greece, facing increased anthropogenic pressures due to pollution and climate change. The main objective of the study was to investigate the succession of microbial planktonic communities, including phytoplankton and protozooplankton, through high-frequency monitoring every two days. The research was conducted with samplings during two distinct periods, summer and autumn of 2023, to capture the rapid changes in the structure of phytoplankton and protozooplankton communities.
A total of 41 taxa were identified, with Diatoms and Dinoflagellates dominating. During the summer, Diatoms had a dominant presence, while in the autumn, the community composition shifted, with Heterotrophic Nanoflagellates (HNF) showing a significant increase in abundance. The abundance of planktonic communities was significantly higher in the summer, reaching a peak of 6485 cells mL-1 on July 14. Biomass also fluctuated, with the highest value in the summer recorded on July 12. Taxa that have the potential to form harmful algal blooms (HABs), such as the genera Pseudo-nitzschia and Dinophysis, were primarily detected during the autumn period.
The study highlights the importance of high-frequency sampling for recording the dynamic changes in planktonic communities. The rapid shifts observed over periods of just a few days demonstrate the significance of this approach for the effective monitoring of marine planktonic communities and, by extension, for improving management practices in coastal ecosystems.
Keywords:
Unicellular planktonic communities, High-frequency monitoring, Coastal ecosystems, Phytoplankton and protozooplankton, Biodiversity and biomass, Harmful algal blooms (HABs)
