primary fields of oceanography announcements geology …myweb.facstaff.wwu.edu/~shulld/esci...
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Announcements
• Third problem site due November 27
– Review calculations
• Fourth problem set (new but short) due Dec. 6th
• A week from Tuesday– quiz on Kirchman reading
(microbes)
• Moving from physical to biological oceanography
• Reading: Ch 13, 325-335, Ch 14?
Primary Fields of Oceanography
Geology Chemistry
Physics Biology
Upwelling
mixed-layer depth
Light attenuation
Bottom topography
Organic C
production &
degradation
Nutrients
Contaminants
Nutrients, light... Phytoplankton Zooplankton
Benthos
Life in the Ocean: Lecture topics and conceptual models
Fish, Birds,
Mammals
Ecosystem Structure and Function:
Function: Organic-matter production, energy flow,
biogeochemical cycles
Structure: Spatial and temporal patterns of organism abundance,
community composition, and species diversity
Food-web model (or energy-flow, bottom-up view):
Microbes
Microzooplankton
DOC
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Topics for today:
I. Important organisms in Puget Sound
A. Nutrients and phytoplankton
B. Zooplankton
C. Microbes
D. Fish, mammals
E. Benthos
II. Primary productivity
A. Definitions
B. Measurement
C. Primary production limiting factors
Organisms and ecosystem function:
What factors limit abundance and
productivity of marine organisms?
Phytoplankton:
Light, nutrients, temperature,
salinity, (also pH, pressure)
Heterotrophs:
Food, temperature, salinity, etc.
Algae
Density
De
pth
Density
De
pth
Density
De
pth
Light
De
pth
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Structure: Ways of classifying marine organisms:
Plankton - drifts (phytoplankton, zooplankton)
Nekton - swims (fish, mammals)
Benthos - remains on the bottom (benthic algae, animals)
Taxonomy
Phytoplankton - protista
Zooplankton - protista, animalia (arthropoda, cnidaria, mollusca)
Nekton - animalia (vertebrata, arthropoda)
Microbes – protista, bacteria, archaea
Benthos - protista, plantae, animalia (many, many phyla)
1. Base of the oceanic food web
2. >half O2 in atm. from phytoplankton.
3. 1 gallon gasoline ≈ 1 metric tonne of plankton biomass.
4. Ecological Indicators of ecosystem health. (monitored by King Cty)
5. Toothpaste, aquarium filters, and SoftScrub®.
6. POISON: Red Tides or Harmful
Algal Blooms
Initiates contaminant biomagnification
Plankton - Greek: πλαγκτός
“that which is made to wander and drift”
Why do we care?
What are the major groups of
phytoplankton?• Diatoms
• Cell wall (frustule) made of silica
• Perhaps 12,000 to 30,000 species
• Two groups (orders:
– Centric (shaped like a petri dish)
– Pennate (shaped like a pen)
• Size ~0.1 mm (0.002 to 0.2 mm)
What are the major groups of
phytoplankton?• Dinoflagellates
“whirling whips”
• Two flagella for locomotion
• Very primitive protists
• ~ ½ photosynthetic and ~ ½
heterotrophic (some mixotrophic)
• Perhaps 2,000 species
• Size ~0.5 mm (0.005 to 1 mm)
• Many species produce toxins
• A few species form chains
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What are the major groups of
phytoplankton?
• Cyanobacteria
• Photosynthetic bacteria!
• Tiny (0.00005-0.04 mm)
• Probably the first photosynthetic
organisms
• Created earth’s oxygen ~ 2 bya
• Very diverse group with 9 major
divisions and three important genera
– Synecococcus
– Trichodesmium
– Prochlorococcus
• Number of species?
What are the major groups of
phytoplankton?
• Microflagellates
• Many other groups of flagellated
phytoplankton
• Size: ~0.01 mm (0.0002 to 0.03 mm)
• Important groups
– Silicoflagellates
– Coccolithophores
– Phaeocystis
Studying phytoplankton
• “Net” plankton
• Bottle collection
• Laboratory cultures
• Mapping biomass
from space
• Molecular
investigations
May
Plankton in Puget Sound
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Phytoplankton of Puget Sound
Diatoms:
Skeletonema costatumChaetoceros debilis
Chaetoceros convolutus
Thalassiosira
aestivalis
Phytoplankton of Puget Sound
Dinoflagellates:
Ceratium fusus
Noctiluca miliaris
Protoperidinium
divergens
Alexandrium
catenella
Phytoplankton of Puget Sound
Other flagellates:
Dictyocha Heterosigma agawashio
Phaeocystis
Cyanobacteria
• major form
– Synechococcus
• In Hood Canal: >70% of cells and ~20% spring biomass is Synechococcus
• In open ocean cyanobacteria can dominate biomass
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Zooplankton of Puget Sound
Copepods: Calanus Pseudocalanus
Acartia
Euchaeta
Zooplankton of Puget Sound
Gelatinous plankton:
Aequorea victoria Pleurobranchia
Oikopleura
Zooplankton of Puget Sound
Chaetognaths
Sagitta elegans
Zooplankton of Puget Sound
Meroplankton:
Crab larvae Cod larva
Urchin larva
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Benthos:
Greek for deep
“benqos”
Hard-bottom intertidal benthos
Soft-bottom benthos
Fish
Size ranges of organisms
of Puget Sound
Summary: Marine organisms and ecosystem function
Primary production:
Removes CO2, nutrients (N, P, Fe, etc.), metals
Converts dissolved CO2 to particulate organic carbon,
which sinks (“Biological Pump”)
Produces oxygen
Respiration:
Releases CO2, nutrients
Uses oxygen
Organic-matter consumption: sends energy throughout food web
Organic-matter production and consumption drives nearly all of the
other biogeochemical cycles
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Diagram by David Karl