1. Aquatic Ecosystems Monday, August 22nd Reminder: HW3 Part II due Wednesday! Midterm Thursday

2. Ecotone: the transition zone between two diverse communities WHAT DID YOU FIND??????

3. Kelp Effect on Waves

4. Kelp forest ecosystem Kelp provides otter habitatSea urchins eat kelp Otters eat sea urchins

5. Kelp forest ecosystem & human values

6. Kelp Effect on Waves

7. Impact of Kelp on Low Productivity Terrestrial Env’ts Example: Channel Islands Kelp detritus = nutrient input to intertidal communities Marine bird and mammals feed on intertidal organisms Feces/guano provide nutrients to terrestrial organisms Biggest impact where ratio of shoreline to area is high

8. Kelp forest ecosystem 30-40 m water depth Determined by light availability Require high concentrations of nutrients Occur mostly in areas of upwelling Provide primary production (food) and habitat!

9. Selective Pressures in Intertidal Zones TidesSalinity Waves

10. Rocky Intertidal Zonation Where to snorkel, rocky shore or sandy beach? Why?

11. Aquatic Ecosystems Oceans Lakes Streams and Rivers Estuaries Freshwater wetlands

12. Some General Questions:  Where does the energy to support aquatic life come from?  How productive are each of the aquatic environments?  What is the limiting factor in each aquatic environments? How are nutrients cycled?  How have humans changed these environments?

13. The open ocean is most like… A) a tropical rain forest B) the boreal forest C) the desert D) chaparral … with regard to productivity.

14. Where is the ocean most productive? Where nutrients are available:  near the coast From upwelling rivers bring nutrients  Polar upwelling –Short, intense productivity Where sunlight is available: Top 100 meters (euphotic zone)

15. Net Primary Productivity (NPP) by Biome

16. Atmospheric/Ocean Coupling surface currents are driven by wind

17. Ocean: surface currents

18. Ocean Primary Productivity

19. Coastal Upwelling Most upwelling occurs in response to longshore winds. Upwelling: increased nutrients, increased primary production good fishing! El Nino brings warm water, shuts down upwelling, bad for fisheries

20. Coastal Upwelling

21. Is Primary Production always good for upper trophic levels? Harmful algal blooms: toxicity or increase in BOD suffocation, starvation Red tide

22. LA Times: Altered Oceans Pulitzer Prize

23. The open ocean is most like… A) a tropical rain forest B) the boreal forest C) the desert D) chaparral … with regard to productivity.

24. Coral reefs  Coral reefs are extremely productive  Visibility is great!  But we know that nutrient-rich water is murky How is this possible? Where are the nutrients? What terrestrial biome does this remind you of?

25. Coral reefs  Efficient cycling of nutrients  Complex relationships between organisms Corals: plants or animals? zooxanthellae in coral intricate food webs

26. Freshwater Ecosystems Lakes, streams and rivers

27. Light Penetration in Lakes Secchi disk Euphotic zone Aphotic zone Sediment eu: well or good a: without

28. Oligotrophic vs. Eutrophic Lakes

29. Thermal Stratification of Lakes Epilimnion Hypolimnion Sediment Summer Thermocline

30. Thermal Stratification of Lakes Thermocline Epilimnion Hypolimnion Sediment (wind) SummerFall Well-mixed profile Sediment

31. Thermal Stratification of Lakes Hypolimnion Thermocline Well-mixed profile Sediment Epilimnion Hypolimnion Sediment (wind) Summer Fall Winter Frozen Warmer Well-mixed profile Sediment Cooling

32. Thermal Stratification of Lakes Hypolimnion Thermocline Well-mixed profile Sediment Well-mixed profile Sediment Epilimnion Hypolimnion Sediment (wind) Summer Fall Winter Spring Frozen (4°C) Well-mixed profile Sediment Cooling Warming

33. Summary  Aquatic Ecosystems Limiting factors (light, nutrients, dissolved oxygen) and Temperature  Rocky Intertidal Zonation and adaptations  Oceans Productivity: euphotic zone/thermocline/nutrients/BOD/algal blooms Open ocean vs. coast –Nutrients: upwelling and coastal inputs Coral Reefs (zooanthellae, coral bleaching, ocean acidification, dynamite fishing)  Lakes… seasonality of: Light penetration (euphotic vs. aphotic zones) Temperature (epilimnion vs. hypolimnion) Oxygen (aerobic vs. anaerobic/anoxic) Nutrients (oligotrophic vs. eutrophic)