Major groups of Phytoplankton

DIATOMS

DINOFLAGELLATES

COCCOLITHOPHORESwww.imagequest3d.com

Diatoms• Microscopic; extremely abundant

• Important food source for marine organisms• Single-cells, chain, loose “clusters”

• Oil droplets in cell - slow sinking

Asterionella – a colony of pennate diatoms; photo by Jan Parmentier

Centriclive diatom www.indiana.edu

Photo Credit: Dr. Neil Sullivan, University of Southern Calif. / National Oceanic & Atmospheric Administration / Dept. of Commerce

Diatoms (Division Chrysophyta)

Coscinodiscus

http://earthguide.ucsd.edu/images/di/img/chloro.jpg

www.imagequest3d.com

Chain Diatoms

Diatomaceous Earth – silicaceous shells piled up over millions of years – used for Paint, Silver Polish, Filters, Insulation

Photo by George Rowlandhttp://life.bio.sunysb.edu/marinebio/pl_08.jpg

Dinoflagellates

• Microscopic • Mostly unicellular

• Responsible for = red tides, bioluminescence

• Noctiluca = “night light”

Noctiluca Bloom

Photo Credit: PJS Franks (Photographer) / National Ocean Service Photo Gallery

Photo by George Rowland

http://life.bio.sunysb.edu/marinebio/pl_08.jpg

Florida Red Tide Bloom of Karenia brevis www.whoi.edu/rtphotos

In addition to adverse health effects, harmful algal blooms are responsible for the loss of millions of dollars from commercial and recreational fisheries and from tourist industries.

ww

w.w

hoi.

ed

u/r

ed

tid

e

Florida Coastal

Zone Scanner Image

of Karenia brevis bloom in Nov 1978

Coccolithophores• One-celled marine plants - live

in large numbers, can make water appear milky or chalky

• Live near surface in brightly lit areas

• Calcareous ooze = White Cliffs of Dover

Alaska and the Bering Sea from SeaWiFS on April 25, 1998. The bright aquamarine water is caused by the huge numbers of coccolithophores. This bloom was present in 1997 and 1998, and appears to be re-occuring in 1999. (Image courtesy Norman Kuring, SeaWiFS Project)

Earthobservatory.nasa.gov/library/coccolithophores

Coccolithophores Emiliania huxleyi & Syracosphaera molischi

Scanning electron photography by Vita Pariente. Microscopy was done at the

Electron Microscopy Center, Texas A&M University.

White Cliffs of Dover

Photo Credit: Dover District Council