Test

1
Test 2 Results by Next Week
2
Biological Productivity
3
Conditions for Life in the Sea

• Consider the main biochemical reaction for life
  in the sea, and on earth in general
• 6H2O 6CO2 energy nutrients C6H12O6 6O2
• Focus on left side of equation
• What is in short supply in the sea and thus
  limits the amount of life in the ocean??

4
Absorbing Nutrients 6H2O 6CO2 energy
nutrients C6H12O6 6O2

• Phytoplankton are base of the food chain
• Most important primary producers of complex
  sugars and oxygen

Lauderia sp.
5
Open Ocean Food Webs
Coccolithophores
ARCOD_at_ims.uaf.edu
Copepods
Barrie Kovish
Pacific Salmon
Vicki Fabry
Pteropods
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Present Ocean Food Web Complex ecosystem
interactions based on a low CO2 ocean
Ocean Food Web
Primary Producers
Upper Trophic Levels
Zooplankton Food Web
Sinking Organic Debris
Provided by James Barry MBARI
Microbial Remineralization
Seafloor community
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Absorbing Nutrients

• Nutrients absorbed by plants through diffusion
  across a semi-permeable membrane

Lauderia sp.
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Diffusionmolecules move from high to low
concentrations
9
Which Nutrients are in Short Supply?

• Nitrogen (N) as Nitrate NO3 (-2)
• Phosphorus (P) as Phosphate PO4 (-2)
• Silicon (Si) as Silicate SiO4 (-2)

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Phosphate and Nitrate in the Pacific
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Silicate in the Pacific
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Biolimiting Nutrients

• N, P, and Si are exhausted first in Eq. surface
  waters during photosynthesis
• Essential to the growth of phytoplankton
• If these biolimiting nutrients increase in sea
  water, life increases
• If these biolimiting nutrients decrease in sea
  water, life decreases
• Where would you expect to find the highest
  biomass in the Pacific??

13
CZCS Global Primary Production
14
How Does Nutrient Distribution Compare
w/Dissolved Oxygen?
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Dissolved O2 Reverse of Nutrients

• O2 is high in the surface and mixed layer
• O2 decreases to a minimum at base of thermocline
• O2 then steadily increases with depth

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Why is the Concentration of Oxygen High in the
Mixed Layer??

• Hint 1 How and where is oxygen produced in the
  sea???
• 6H2O 6CO2 energy nutrients C6H12O6 6O2
• Hint 2 How can oxygen be mixed downward from
  the atmosphere into the ocean?

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How is Oxygen Removed from the Thermocline
Slightly Below??
18
Dead and decaying organic matter sinks downward
from surface waters

• Rate of sinking decreases as it encounters the
  cold, dense water of the thermocline
• Material decays (oxidizes) at the thermocline,
  which strips O2 out of the water and returns
  nutrients to the sea
• Cold, nutrient-rich water of the thermocline is
  returned to sunlit surface waters by way of
  upwelling

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CZCS Global Primary Production
20
Marine Ecology
21
Basic Ecology

• physical and chemical parameters affecting
  distribution and abundance
• An ecosystem includes both the living (biotic)
  and non-living (abiotic) portions of the
  environment.
• Examples include salt marshes, estuaries, coral
  reefs, the North Pacific Gyre.

22
Classification of Organisms by Environment

• horizontal neritic oceanic
• vertical
• epipelagic (top) / euphotic (good)
• mesopelagic (middle) / disphotic (low)
• bathypelagic (deep) / aphotic (without)
• abyssopelagic (bottomless)

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Divisions of the Marine EnvironmentFigure 9-1
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Classification of Organismsby Lifestyle

• Scientists have established another
  classification scheme to categorize biota on the
  basis of lifestyle. The major groups are
• plankton (floaters)
• nekton (swimmers)
• benthos (bottom dwellers)

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Plankton

• weak swimmers, drifters, unable to counteract
  currents.
• Phytoplankton (plants)
• Zooplankton (animals)

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Nekton

• active swimmers capable of counteracting
  currents.
• Fish
• Squids
• Reptiles
• Birds
• Mammals

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Distribution of Marine Lifestyles

• 16.7 of Earths animals are marine
• 2 inhabit pelagic environment (most of the
  oceans are cold and dark)
• 98 are benthic!

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Benthos

• Epiflora or epifauna live on the sea bottom.
• Infauna live in the sea bottom.
• Benthic plants - restricted to shallow waters
  (light)
• Benthic animals occur everywhere from shallow
  depths to the deep sea.

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Research Video ClipsLive fast, die young...
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Hydrostatic Pressure

• Pressure caused by the height of water.
• Function of water height and water density
• Pressure generally increases at a rate of 1 atm
  per 10 m of water.
• ( or 16 psi per 10 m depth)

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Think Youre Under Pressure Now?
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Hydrostatic Pressure(Cont.)

• enormous in the deep sea yet animals live there.
  
• Animals do not contain gases.
• However, mesopelagic fish which have gas-filled
  swim bladders to help maintain neutral buoyancy
• unable to move rapidly between depths
• pressure change could cause bladder explode.

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Oregon Coast Field Trip - Sat., May
30thdusk.geo.orst.edu/oceans/field.html

• Be here by 715 a.m.
• 730 - Busses leave from Wilkinson lot
• 830 - HMSC Visitor Center
• 1000- Travel to Seal Rock State Park

• 1030 - Seal Rock volcanic rocks and tide pools
• 1200 - Lunch at Seal Rock (bring your own)
• 1230ish - Return to Corvallis
• Back by 200

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Required Field Trip Guidedusk.geo.orst.edu/oceans
/field.html

• Answers to bolded questions in guide
• Turn assignment in to your TA
• Due by 500 p.m., June 5th
• This constitutes LAB 9