1. Test #2 Results by Next Week

2. Biological Productivity
Chapter 10:
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. The Marine Food Web

6. Absorbing Nutrients
Nutrients absorbed by plants through diffusion across a semi-permeable membrane
Lauderia sp.

7. Diffusion: molecules move from high to low concentrations

8. Which Nutrients are in Short Supply?
Nitrogen (N) as Nitrate NO3 (-2)
Phosphorus (P) as Phosphate PO4 (-2)
Silicon (Si) as Silicate SiO4 (-2)

9. Phosphate and Nitrate in the Pacific

10. Silicate in the Pacific

11. 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??

12. CZCS Global Primary Production

13. How Does Nutrient Distribution Compare w/ Dissolved Oxygen?

14. 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

15. 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?

16. How is Oxygen Removed from the Thermocline & Slightly Below??

17. 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

18. CZCS Global Primary Production

19. Marine Ecology
Chapter 9

20. 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.
factors regulating the distribution and abundance of organisms in the ocean.
influence of physical and chemical parameters on organisms in the various ecosystems that constitute the ocean.
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.

21. Classification of Organisms by Environment
horizontal: neritic | oceanic
vertical:
epipelagic (top) / euphotic (good)
mesopelagic (middle) / disphotic (low)
bathypelagic (deep) / aphotic (without)
abyssopelagic (“bottomless”)

22. Divisions of the Marine Environment Figure 9-1

23. Classification of Organisms by 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)

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

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

26. Distribution of Marine Lifestyles
16.7% of Earth’s animals are marine
2% inhabit pelagic environment (most of the oceans are cold and dark)
98% are benthic!

27. 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.

28. Research Video Clips: “Live fast, die young...”

29. 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.
Temperature, salinity …
Temperature controls rates of chemical reactions and thus metabolic rates, growth rates, feeding rates, etc.
Salinity used for growth as well, tolerance to salinity affects distribution

30. 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)
pressure at seafloor of Juan de Fuca R?

31. Think You’re Under Pressure Now?

32. 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.

33. Oregon Coast Field Trip - Sat. , June 3rd dusk. geo. orst
Oregon Coast Field Trip - Sat., June 3rd dusk.geo.orst.edu/oceans/field.html
12:30 - Seal Rock volcanic rocks and tide pools
1:30ish - Return to Corvallis
Back by ~3:00
Be here by 8:30 a.m.
8:45 - Busses leave from Wilkinson lot
10:00 - HMSC Visitor Center
11:30 - Travel to Sea Rock & Lunch at Seal Rock park (bring your own)

34. Required Field Trip Guide dusk.geo.orst.edu/oceans/field.html
Answers to bolded questions in guide
Turn assignment in to your TA
Due by 5:00 p.m., June 9th
This constitutes LAB 9