Micro-tidal dependent phytoplankton C-biomass dynamics over two shallow tropical coral reefs

  • Shamimtaz Bibi Sadally University of Mauritius
  • Nawsheen Taleb-Hossenkhan University of Mauritius
  • Beatriz Casareto Shizuoka University
  • Yoshimi Suzuki Shizuoka University
  • Ranjeet Bhagooli University of Mauritius
Keywords: C-biomass, chlorophyll a, environmental factors, micro-phytoplankton, micro-tides


This study investigates micro-tidally induced variations in micro-phytoplankton carbon biomass (C-biomass), concentrations of chlorophyll a, nitrate, phosphate and silicate, temperature, salinity and pH at three zones (near-coast, lagoon and reef) at two sites (Flic-en-Flac (FEF) and Belle Mare (BM)) on two consecutive days covering two high and low tides in August (winter) and in November (summer) 2011. At FEF, 36 different genera of micro-phytoplankton were recorded, including 29 bacillariophyceae, 5 dinophyceae and 2 cyanophyceae. At BM, 34 different genera of micro-phytoplankton were recorded, including 31 bacillariophyceae, 3 dinophyceae and 2 cyanophyceae. At low tides the total micro-phytoplankton C-biomass (TMPB) and nutrient levels were significantly higher compared to those at high tides.  At both sites, zonal variation in TMPB was evident with significantly higher C-biomass at the near-coast. Only bacillariophyceae and dinophyceae C-biomass along with nutrient levels exhibited seasonal variation with higher values in summer. Bacillariophyceae was dominant, followed by cyanophyceae and dinophyceae, irrespective of micro-tidal changes indicating their ability to tolerate a wide range of micro-tidally induced environmental changes. These findings provide insights on the effect of micro-tidal cycle on micro-phytoplankton dynamics and might have implications for carbon cycling over shallow tropical coral reefs and other inter-connected coastal ecosystems.

Author Biographies

Shamimtaz Bibi Sadally, University of Mauritius
Nawsheen Taleb-Hossenkhan, University of Mauritius
Beatriz Casareto, Shizuoka University
Yoshimi Suzuki, Shizuoka University
Ranjeet Bhagooli, University of Mauritius

Journal Identifiers

eISSN: 0856-860X
print ISSN: 0856-860X