VARIABILITY IN PHYTOPLANKTON PIGMENT COMPOSITION IN MERSIN BAY

Year 2017, Volume: 32 Issue: 1, 49 - 70, 23.01.2017

Nebil Yücel , Zahit Uysal Süleyman Tuğrul

https://doi.org/10.18864/TJAS201705

Abstract

Phytoplankton
pigment composition and associated biochemical (chlorophyll a,
nitrate+nitrite, ammonia, phosphate,
silicate) and physical (temperature, salinity) parameters were studied
seasonally in the river-fed eutrophic coastal and oligotrophic offshore waters
of the Mersin Bay located on NE Mediterranean. Total chlorophyll a
concentrations varied seasonally between 0.023 - 7.73 µg/l in the river
fed coastal zone (salinity: 36.54-39.68), exhibiting less seasonality in the
offshore station (0.01 – 0.91 µg/l). Seven
different phytoplankton taxa (namely diatoms,
cyanobacteria, prymnesiophytes, dinoflagellates, chlorophytes, chrysophytes,
prochlorophytes), determined by High
Performance Liquid Chromatography (HPLC), were consistently present in the
coastal waters during 2008-2011. The predominant diatom and
coccolithophorid taxa in the river-fed coastal waters were replaced by
prokaryotic picoplankters (cyanobacteria & prochlorophytes) and
prymnesiophytes in the offshore. Contribution of prokaryotic picoplankton and
eukaryotic nanoflagellates to total chlorophyll (% 23 to 47 and % 28 to 43,
respectively) increased by about 50% from the coastal to the offshore station.
Contribution of large cells to total chlorophyll decreased from 49% to 10%
towards offshore. Prochlorophytes were observed as the dominant group in
relatively colder and darker deep waters. 

Keywords

Pigments, HPLC, phytoplankton, nutrients, northeastern Mediterranean

References

• Yucel, N. (2008). Phytoplankton pigment distribution in the Cilician basin (northeastern Mediterranean). MSc Thesis, Institute of Marine Science, Middle East Technical University, Mersin, Turkey, 175 pp, unpublished.