Phytoplankton group dynamics in the Bay of Marseilles during a 2-year survey based on analytical flow cytometry

Citation
G. Gregori et al., Phytoplankton group dynamics in the Bay of Marseilles during a 2-year survey based on analytical flow cytometry, CYTOMETRY, 44(3), 2001, pp. 247-256
Citations number
49
Categorie Soggetti
Medical Research Diagnosis & Treatment
Journal title
CYTOMETRY
ISSN journal
01964763 → ACNP
Volume
44
Issue
3
Year of publication
2001
Pages
247 - 256
Database
ISI
SICI code
0196-4763(20010701)44:3<247:PGDITB>2.0.ZU;2-K
Abstract
Background: The Bay of Marseilles is under the influence of a large urban c oncentration and its maritime activities. All of them discharge compounds ( hydrocarbons, excess nutrients, heavy metals, chemicals, etc.) that can alt er the marine ecosystem. To investigate whether ultra-phytoplankton (< 10 m um) could be used as biosensors for their own ecosystem, a 2-year survey wa s conducted in the Bay of Marseilles. Methods: Seven stations monitored water mass and potential anthropic effect s in the bay. Seawater samples were collected monthly or bimonthly at three depths, prefiltered, fixed, and kept in liquid nitrogen until flow cytomet ric analysis. Results: Five categories were created: Prochlorococcus, picoeukaryotes (<2 mum), nanoeukaryotes I (2-6 mum), nanoeukaryotes II (6-10 mum), and Synecho coccus (<1.5 mum). Artificial neural network analysis (Kohonen self-organiz ing maps) produced the same number of clusters as cluster analysis with Win list software (Verity Software House). Conclusions: In addition to the wide variabilities in abundance and biomass , there were a strong seasonal signal and sporadic events. Lessons are deri ved from this study for future monitoring of marine microorganisms. (C) 200 1 Wiley Liss, Inc.