Marine Primary Producers

Macroalage & Phytoplankton

Photo: C. Schvarcz (Steward Lab, UH Manoa) OCN 201 Biology Lecture 4

http://video.conncoll.edu/f/pasiv/lucid/Cyanophora-900.html

Thursday, November 13, 2014 Primary production

• The production of organic compounds from atmospheric or aquatic carbon dioxide, principally through the process of photosynthesis (or chemosynthesis) • Carried out by autotrophs • On land primary producers are mostly macroscopic • In the sea nearly all primary production is due to microscopic phytoplankton

Thursday, November 13, 2014 Terrestrial Primary Producers

Large Marine Primary Producers Macroalgae & Seagrasses

Thursday, November 13, 2014 Kelp Forest Locations Macroalgae mostly limited to coastal areas

Exception: Sargassum, a planktonic macroalga

Thursday, November 13, 2014 BUT: most life in the sea is microscopic including the primary producers and consumers

Picoeukaryote

Bacterium

Large Flagellate

Diatom

Thursday, November 13, 2014 How many phytoplankton in a liter of seawater?

Bigger Diatoms 1,000 Dinoflagellates 10,000 Coccolithophores 20,000 Nanoflagellates 1,000,000 Smaller Cyanobacteria 100,000,000

very rough numbers; they vary a lot!

Thursday, November 13, 2014 Prokaryotic Phytoplankton (Cyanobacteria)

• Prochlorococcus • Synechococcus (and others)

Responsible for a lot of the primary productivity in the open ocean

Thursday, November 13, 2014 Eukaryotic Phytoplankton have Plastids that originated as symbiotic cyanobacteria

Thursday, November 13, 2014 Some Eukaryotes Steal Plastids from Others This process is called kleptoplasty

Thursday, November 13, 2014 Eukaryotic Phytoplankton

• Picoeukaryotes • Diatoms • Dinoflagellates • Coccolithophores

Thursday, November 13, 2014 Picoeukaryotes Ostreococcus - smallest free-living eukaryote By eye François

Light Electron Microscope Microscope

Universi Wenche Eikrem and

Thursday, November 13, 2014 Picoeukaryotes

Micromonas pusilla

Thursday, November 13, 2014 Diatom Coccolithophore

Silica frustule Calcium carbonate plates cyanobacterium

Cellulose thecal plates picoeukaryote

Dinoflagellates

Thursday, November 13, 2014 DIATOMS Fragilaria Navicula

Chaetocerous

http://bioloc.oce.orst.edu/SherrLab/BESTMG9%20epi%20Chaeto.jpg Thursday, November 13, 2014 Siliceous Sediments

http://www.marinebio.net/marinescience/02ocean/mgbottom.htm

http://www.bhikku.net/archives/03/img/diatoms.JPG

Thursday, November 13, 2014 Dinoflagellates

Thursday, November 13, 2014 Emiliania huxleyi

http://images.quickblogcast.com/77583-67933/coccobloom.JPG http://media-2.web.britannica.com/eb-media/94/74594-004-02A9BBFF.jpg Thursday, November 13, 2014 Summary • Kelp and sea grasses important in nearshore in nutrient rich areas BUT most primary producers are microscopic • Photosynthetic bacteria (cyanobacteria) are most abundant primary producers on the planet • The larger photosynthetic planktonic eukaryotes are also very abundant • Some important groups: diatoms & coccolithophores have hard shells that create massive (and inspirational) mineral deposits

Thursday, November 13, 2014