Test #2 Results by Next Week

1. Test #2 Results by Next Week

2. 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 Nutrients6H2O + 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. Classification of Organisms by Environment • horizontal: neritic | oceanic • vertical: • epipelagic (top) / euphotic (good) • mesopelagic (middle) / disphotic (low) • bathypelagic (deep) / aphotic (without) • abyssopelagic (“bottomless”)

21. Divisions of the Marine EnvironmentFigure 9-1

22. 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)

23. Plankton • Plankton are weak swimmers, and are known as drifters, unable to counteract currents. The group includes: • Phytoplankton (plants) • Zooplankton (animals)

24. Nekton • Nekton are active swimmers capable of counteracting currents. The group includes a diversity of organisms including: • Fish • Squids • Reptiles • Birds • Mammals

25. 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!

26. Benthos • Thebenthos includes organisms attached to or living on or in the sea bed. This group includes plants and animals. • Epiflora or epifauna live on the sea bottom. • Infauna live in the sea bottom. • Benthic plants are restricted to shallow waters because of their requirement for light. • Benthic animals occur everywhere from shallow depths to the deep sea.

27. Basic Ecology • physical and chemical parameters 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.

28. TemperatureFigure 9-10 • controls rates of chemical reactions and thus metabolic rates, growth rates, feeding rates, etc.

29. Salinity • Salinity is a basic property of seawater and it too affects marine organisms. • Many of the elements in seawater are utilized by marine organisms for growth. • Salinity tolerance is also important in limiting distribution.

30. Diffusion:molecules move from high to low concentrations

31. Diffusion/OsmoregulationFigure 9-12 Some organisms can regulate the movement of water into and out of the cells by osmoregulation.

32. 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)

33. Think You’re Under Pressure Now?

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

35. Be here by 7:00 a.m. 7:15 - Busses leave from Wilkinson lot 8:30 - Seal Rock volcanic rocks and tide pools 11:00 - Lunch at Seal Rock park (bring your own) 12:00 - HMSC Visitor Center 1:30ish - Return to Corvallis Back by 2:30-3:00 Oregon Coast Field Trip - Sat., May 21st dusk.geo.orst.edu/oceans/field.html

36. Required Field Trip Guidedusk.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 3rd

37. Extra Credit #1A - Climate Change Lecture • Bruce Wielicki, NASA, April 4, 2005 • Not enough room in LaSells that evening • Watch DVD finally on reserve in library, VR 695 • 1-page reaction paper, typed, double-spaced • Overview, your reaction, and how content relates to this course • Due by 5:00, Thursday, June 2nd • Hand in to your TA please !!! • Worth up to 10 pts. on final exam