Phytoplankton What are the phytoplankton? How do the main groups differ? Phytoplankton Zooplankton Nutrients
Plankton wandering or drifting (incapable of sustained, directed horizontal movement)
www.shellbackdon.com Nekton Active swimmers
Components of the Plankton Virioplankton: Viruses Bacterioplankton: Bacteria free living planktobacteria; epibacteria attached to larger particles Mycoplankton: Phytoplankton: Zooplankton: Fungi Photosynthetic microalgae, cyanobacteria, and prochlorophytes Heterotrophic Protozooplankton (unicellular) and Metazooplankton (larval and adult crustaceans, larval fish, coelenterates )
Components of the Plankton Ichthyoplankton: Meroplankton: Holoplankton: Planktonic fish (generally, eggs and larval stages) Planktonic organisms that have a sedentary stage. For example, phytoplankton with resting stages in sediments Wholly planktonic
Components of the Phytoplankton: Older scheme Inspecting a small plankton net. In: "From the Surface to the Bottom of the Sea" by H. Bouree, 1912, Fig. 49, p. 61. Library Call Number 525.8 B77. Netplankton: Plankton that is retained on a net or screen, usually 20-100 µm Nanoplankton: Plankton that passes the net, but which is > 2 µm Ultrananoplankton: Plankton < 2µm
Components of the Plankton (older scheme) Netplankton: Plankton that is retained on a net or screen, usually 20-100 µm Nanoplankton: Plankton that passes the net, but which is > 2 µm Ultrananoplankton: Plankton < 2µm Microzooplankton: Zooplankton in the microplankton (i.e., < 200 µm)
Length Scales to Define Plankton Groups Sieburth, J. M., Smetacek, V. and Lenz, J. (1978). Pelagic ecosystem structure: Heterotrophic compartments of the plankton and their relationship to plankton size fractions. Limnol. Oceanogr. 23: 1256-1263.
Terminology and Scales: SI Units FRACTION PREFIX SYMBOL EXAMPLE 10-1 deci d decimeter, 10cm, length of a planktivorous fish 10-2 10-3 10-6 10-9 10-12 10-15 10-18 centi milli micro nano pico femto atto c m µ n p f a 1 centimeter, diameter of a ctenophore 1 millimeter, length of a copepod 1 micrometer, diameter of a very small phytoplankter or a large bacterium 1 nanogram, weight of a fairly small phytoplankter 1 picogram, chlorophyll content of one small phytoplankter 1 femtogram, amount of ATP in a phytoplankter att s a small number!
Scales: The ocean is a dilute environment! SOME CHARACTERISTIC SCALES (values representative of coastal waters to an order of magnitude) organism linear dimension numerical density mm3 m-3 (ppb) spacing in body lengths copepod 1 mm 5 liter -1 2600 6 cm 60 dinoflagellate 35 µm 10 ml -1 225 5 mm 150 diatom 10 µm 10 3 ml -1 525 1 mm 100 cyanobacterium 0.6 µm 10 5 ml -1 11 200 µm 350 bacterium 0.5 µm 10 6 ml -1 65 100 µm 200 virus 0.07 µm 10 7 ml -1 2 50 µm 650
Characterizing Constituents of the Water Detritus: Seston: Tripton: DOM: CDOM: Neuston: Allochthonous: Autochthonous: Matter of organic origin, but incapable of reproduction (dead) All suspended particulate matter The non-living part of seston Dissolved organic matter (passes a fine filter) Chromophoric (colored) DOM Inhabiting the surface layer Developed or originating from elsewhere Endemic: originated locally
Modes of Nutrition Autotrophic: Auxotrophic: Heterotrophic: Mixotrophic: No material of organic origin is required for growth and reproduction Physiological requirement for one or more organic compounds, but C is obtained autotrophically Growth depends on organic material Autotrophic and heterotrophic nutrition Photosynthetic mixotrophs can consume organic matter by phagotrophy (engulfing particles) and osmotrophy (uptake of dissolved organic materials)
Chlorophyll pigment is often equated with phytoplankton biomass Phytoplankton pigments influence ocean color
All phytoplankton were not made equal... Even though phytoplankton are often considered as light absorbers, packages of pigment, or organic particles, they are biologically very diverse - Phylogenetic - Metabolic - Habitat/Niche Space
Light energy is collected by photosynthetic pigments All plants have chlorophylls and carotenoids Some groups (cyanobacteria, cryptophytes, red algae) have phycobiliproteins Pigments are used to infer species composition Pigmentation varies with growth conditions
PHYTOPLANKTON Procarya (cyanobacteria (i.e., Synechococcus, Prochlorococcus), N 2 fixers (i.e., Trichodesmium)) Eucarya (Cryptophyceae, Diatoms, Dinoflagellates, Coccolithophores, Phaeocystis, Chattonella )
The Taxonomic Groups of Phytoplankton: An Overview 1. Bacteria (prokaryotes) Eubacteria (heterotroph) Archebacteria or Archaea (heterotroph) Cyanobacteria (phototroph) "real Cyanobacteria" filamentous cyanobacteria, fix nitrogen coccoid cyanobacteria Prochlorophytes (recently made a new division) 2. Algae (eukaryotes) Chromophyta (possess chl a and c) Cryptophyceae Dinophyceae Chrysophyceae Prymnesiophyceae Bacillariophyceae (diatoms) Raphidophyceae Chlorophyta (possess chl a and b) Chlorophyceae Prasinophyceae Euglenophyceae The taxonomic composition of phytoplankton does matter...
Phylogenies are under constant revision For our purposes, the older classifications are still useful http://tolweb.org/tree?group=stramenopiles&contgroup=eukaryotes Page copyright 1995 Mitchell L. Sogin and David J. Patterson
Discovered in 1979 very small (ca. 1 µm) contains phycoerythrin PROKARYOTES (continued): Synechococcus can fluoresce orange or red counted with epifluorescence microscopy or flow cytometry http://www.woodrow.org/teachers/esi/1999/ princeton/projects/cyanopigs/data.htm reprinted from Johnson and Sieburth 1979
Discovered in 1988 Very small (<1.0 µm) Divinyl chl a Counted by flow cytometry PROKARYOTES (continued): Most abundant autotroph on earth Prochlorococcus reprinted from Johnson and Sieburth 1979
PROKARYOTES (continued): Trichodesmium (Oscillatoria thiebautii) Forms aggregates Fixes nitrogen Can migrate vertically May transport phosphate from depth to near surface New production transports more C Trichodesmium bloom www.aims.gov.au/pages/research/ trichodesmium/tricho-01.html http://www.botan.su.se/fysiologi/cyano/tricho.jpg
EUKARYOTES having a true nucleus Chromophyta - containing chlorophyll a and c Coscinodiscus waelesii Phytopia CD-ROM Bigelow Laboratory
EUKARYOTES (continued): Division Chromophyta Class Cryptophyceae Motile Contain phycobiliproteins Can be recognized by size and fluorescence (flow cytometry) Cryptomonas www.unex.es/botanica/ clases.htm http://mac2031.fujimi.hosei.ac.jp/pdb/images/mastigophora/cryptomonas/cryptomonas.jpg
EUKARYOTES (continued): Division Chromophyta Class Bacillariophyceae (Diatoms) Cannot swim; Can regulate buoyancy (some can migrate) Require silicon; Encased in Pill-box shaped silica frustule Important in coastal areas and spring blooms http://www1.tip.nl/~t936927/art_deco.html www.oregonbd.org/class/chap2.htm
Diatoms P. Roger Sweet, Indiana University www.coastalstudies.org/stellwagen/phyto.htm
Diatoms pennate pennate Images from http://www.microscopy-uk.org.uk/mag/wimsmall/diadr.html Silica frustule Side View epitheca hypotheca New centric Looking Down on the Valve pennate centric
EUKARYOTES (continued): Division Chromophyta Class Pyrrophyta (Dinoflagellates) Motile; Can migrate vertically Red tides and shellfish poisoning There are autotrophic and heterotrophic species www.jochemnet.de/fiu/phaeocystis.gif
Dinoflagellates: Some are bioluminescent Noctiluca Noctiluca bloom http://www.microscopy-uk.org.uk/mag/art98/nocti.html www.redtide.whoi.edu/hab/rtphotos/rtphotos.html
Dinoflagellates Naked Noctiluca
EUKARYOTES (continued): Division Chromophyta Class Prymnesiophyceae (Haptophyceae) Coccolithophores CaCO 3 skeletal plates pco 2 increases DMS production Near-real-colour SeaWiFS image of a coccolithophore bloom in the Bering Sea, April 1998. earthguide.ucsd.edu/demo/zalaska/08_03_1999a.html www.oregonbd.org/class/chap2.htm Emiliania huxleyi earthguide.ucsd.edu/images/eg/img/ehuxleyi.gif
Coccolithophores
Coccolithophores
EUKARYOTES (continued): Division Chromophyta Class Prymnesiophyceae (Haptophyceae) Phaeocystis Jelly-like colonies clog nets and cause big problems on beaches in Europe Food-web alterations DMS producer Common in Antarctic http://www.icbm.de/~mathmod/pages/projects/questionna ire/figure/phaeocystis.gif http://www.coastalstudies.org/stellwagen/ph yto.htm www.jochemnet.de/fiu/phaeocystis.gif www.bio.uva.nl/lesbrieven/tomtahey/bovenbouwtekst3.htm
EUKARYOTES (continued): Division Chromophyta Class Chrysophyceae Silicolagellates, Pelagomonas, Aureococcus Aureococcus brown tides http://techcenter.southampton.liu.edu/~cgobler/browntide.htm
EUKARYOTES (continued): Division Chromophyta Class Raphidophyceae Chattonella, Fibrocapsa, Heterosigma toxic or harmful blooms Chattonella marina Chattonella antiqua www.marine.kais.kyoto-u.ac.jp Cells of Chattonella marina showing different forms (ovoid, pointed-end and sausageshaped) and a temporary cyst. www.niwa.cri.nz/pgsf/marinebiodiversity/ima ges/algae6.jpg http://www.uio.no/miljoforum/natur/fj_hav/i mg/chat_0.gif
Sampling/Counting
Sampling/Counting Utermöhl Settling chambers
Sampling/Counting Flow cytometer
Sampling/Counting
Sampling/Counting CHEMTAX (HPLC) http://www-ocean.tamu.edu/~pinckney/chemtax.htm