Cross-shelf phytoplankton dynamics in the northeastern Levantine Basin.
A time series sampling program at monthly intervals was carried out at three stations across the shelf in the northeastern Levantine basin to collect phytoplankton samples and associated physical (temperature, salinity, secchi disc depth) variables over a year. Quality and quantity of phytoplankton varied significantly across the shelf in time. Total 71 diatom, 40 dinoflagellate, 4 silicoflagellate and 17 coccolithophore species have been identified from the study area. Diatoms’ contribution to total phytoplankton abundance was maximal during autumn and spring in the nearshore and only during spring in the mid shelf. Coccolithophores formed the dominant group almost throughout the year except May and June in the offshore. Dinoflagellates formed the least abundant group in the shelf over the year. Phytoplankton species have been found the most abundant and diverse during spring when the river runoff to the basin was maximal. In general, a decreasing trend in phytoplankton abundance towards offshore was prominent. Phytoplankton has been found most abundant in the entire shelf during spring and early summer reaching a peak level of 2.7 x 106 cells/l during May in the shallowest station. A huge difference in quantity was observed in phytoplankton contents of the nearshore and offshore waters during summer. Multivariate analyses have shown formation of distinct seasonal phytoplankton assemblages throughout the year. Based on Spearman’s rank correlation analysis, a highly significant negative correlation (n=35, rs= -.587, P < 0.01) was observed between phytoplankton abundance and surface salinity. Superimposed surface temperatures seemed to better illustrate seasonal clusters relative to surface salinity plots.
| Main Author: | |
|---|---|
| Format: | Journal Contribution biblioteca |
| Language: | English |
| Published: |
2020-12-31
|
| Subjects: | abundance, distribution, ASFA_2015::P::Phytoplankton, ASFA_2015::B::Biodiversity, |
| Online Access: | http://hdl.handle.net/1834/17952 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|