Exploring Aquatic Life Zones and Organisms

1. Aquatic Life Zones The Hydrosphere: Part 1

2. Aquatic Life Zones • Types of organisms in an aquatic ecosystem are mainly determined by salinity(amount of salt): • Saltwater/ Marine life zones • Freshwater life zones

3. Limiting Factors • All zones that we discuss have limiting factors. • So what is a limiting factor? • Limiting factor: a resource or environmental condition that limits the growth, abundance, or distribution of an organism or a population of organisms in an ecosystem.

4. Limiting factors that affect aquatic organisms: • Temperature • Availability of light for photosynthesis • Confined to Euphotic (photic) zone • Dissolved oxygen content • Decreases with depth • Availability of nutrients (CO2, NO3-, PO43-) • CO2 increases with depth • Turbidity: degree of cloudiness in water • Inhibits photosynthesis

5. Why are our oceans important? • List at least reasons our oceans are important. • http://www.ted.com/talks/sylvia_earle_s_ted_prize_wish_to_protect_our_oceans

6. What We Get From The Ocean: • Climate control • Nutrient cycling • Habitats • Food • Oil • Etc.

7. Marine Zones

8. Note Break!! • Looking at the words phytoplankton and zooplanktion, what is the difference between the two organisms? • Remember what you know about the prefix zoo and the definition of phyto is something pertaining to or derived from plants.

9. Types of Aquatic Organisms: • Plankton: free floating organisms; 3 types: • Phytoplankton • = Primary producers • Ex: Diatoms, cyanobacteria • Zooplankton • = Primary and secondary consumers • Single-celled to large invertebrates like jellyfish • Ultraplankton • Tiny photosynthetic bacteria

10. Plankton!!!

11. Beautiful plankton • http://www.planktonchronicles.org/en/episode/plankton

12. Types of Aquatic Organisms cont.: • Nekton • Strong swimmers: fish, turtles, whales • https://www.youtube.com/watch?v=B6M_XgiONoo&index=4&list=PL8B8EDD0D02DA14B7 • Benthos • Bottom dwellers: oysters, sea stars, clams, lobsters, crabs, worms • Decomposers: mostly bacteria

13. Major Life Zones

14. 3 Major Zones • Horizontal Zones (Extending from land out to sea) • EX: Intertidal zone

15. Limiting Factors in the Horizontal Zone • Temperature • Salinity • Nutrient availability

16. 3 Major zones • Vertical life zones

17. Limiting Factors of Vertical Zones • Temperature • Nutrient availability • Available sunlight • DO • As you move down through the zones all of these factors decrease. • Colder, darker, less dissolved oxygen, etc.

18. 3 Major Zones • Benthic Zones: Everything on the bottom. Includes all zones.

19. Limiting Factors in the Benthic Zone • Organisms that are benthic must adapt to the limiting factors listed in the zone where they live. • For example, a barnacle in a tidal pool will have different limiting factors than organisms on a deep sea vent.

20. Major Marine Ecosystems • Coastal Ecosystems • From shore to edge of continental shelf • Warm, nutrient rich, shallow • High in nutrients because of increased photosynthesis • Contains 90% of all marine species & most fisheries

22. Coastal Ecosystems: ecological and economic services • Maintain water quality by filtering: • Toxic pollutants • Excess plant nutrients • Sediments • Provide food, timber, fuelwood, habitats • Reduce storm damage and erosion

24. Types of Coastal Ecosystems • Estuaries: where rivers meet the sea Questions with video https://www.youtube.com/watch?v=XLumSN4G5P4 (5 min) B. Coastal Wetlands: land covered with water all or part of year: • Inlets, bays, sounds, mangrove forests, salt marshes • https://www.youtube.com/watch?v=jmebAjdMrLs (3 min)

25. Coastal Ecosystems: c. Coral Reefs • Formation • Tiny animals (polyps) secret calcium carbonate shells, which become coral reefs • Polyps and zooxanthellae algae have mutualistic relationship: • Algae provide oxygen from photosynthesis & chemical energy • Coral polyps provide home • https://www.youtube.com/watch?v=nWyw5H88PBw (3 min)

26. Coastal Zone: Coral Reefs • Ecosystem Services: • Marine equivalent of tropical rain forests • Provides habitat for one-fourth of all marine species • Moderates climate b/c takes up CO2 • Economic/ Social Services: • Food • Potential medicine • Employment & Recreation https://www.youtube.com/watch?v=cbN161yBBGA (4 min)

27. Coastal Zone: Coral Reefs • Causes of Degradation: • (Human-caused) Warmer ocean temperatures leading to coral bleaching: kills algae and thus the polyps • https://www.youtube.com/watch?v=iW8nCALx5iA

28. How do we contribute to coral bleaching? • https://www.youtube.com/watch?v=aEdoizgeNJk

29. Open Ocean: Three vertical zones: • Euphotic zone: lit upper zone • Phytoplankton perform photosynthesis • Nutrient levels low & d-Oxygen levels high • Have fast swimming, predatory fish • Bathyal zone • Dimly lit, few producers • Have zooplankton and smaller fishes

30. Open Ocean: Three vertical zones: • Euphotic zone • Bathyal zone • Abyssal zone • Dark & cold • No photosynthesis, little d- oxygen • High nutrients • Have deposit & filter feeders (eat marine snow), slow fish • https://www.youtube.com/watch?v=BXGF3XS-yAI (2 min)

31. Deep Sea Adaptations • https://www.youtube.com/watch?v=UXl8F-eIoiM

32. Major threats to marine systems: • Coastal development • Habitat destruction • Overfishing • Use of fishing trawlers • Pollution • Introduction of invasive species • Climate change

33. Ocean Acidification • https://www.youtube.com/watch?feature=player_embedded&v=cAwZ7VCYn44 • https://www.youtube.com/watch?v=5cqCvcX7buo (20 min)

34. Aquatic Life Zones • Freshwater Zones: services: • Climate moderation • Nutrient cycling • Flood control • Habitat • Food • Recreation & employment • Etc.

35. Freshwater Life Zones: includes: • Lentic(standing) bodies of freshwater: • Lakes • Ponds • Inland wetlands • Lotic (flowing) systems of freshwater: • Streams • Rivers

36. Lakes: bodies of standing fresh water formed when precipitation, runoff, or groundwater seepage fill depressions in earth’s surface

37. Aquatic Life Zones • 4 Lake Zones: • Littoral zone • Near shore with rooted plants • High biodiversity: turtles, frogs, crayfish, some fish • Limnetic zone • Open, sunlight area away from shore • Main photosynthetic zone • Some larger fish

38. Lake Zones: • Profundal zone • Deep water too dark for photosynthesis • Some fish • Benthic zone • Decomposers & detritus feeders • Some fish • Nourished primarily by dead matter

39. Aquatic Life Zones • Lake Types Based on Nutrient Levels: • Oligotrophic lakes • Low nutrients and low NPP • Very clear water • Eutrophic lakes • High nutrients and high NPP • Murky water with high turbidity • Cultural (artifical) eutrophication: input of excess nutrients (fertilizers) causing excess algal growth

40. Oligotrophic lake

41. Eutrophic lake

42. The Effect of Nutrient Enrichment on a Lake

43. Aquatic Life Zones • Freshwater Degradation: • Dams destroy habitat • Flood control levees and dikes along rivers alter flow & destroy habitat • Pollutants from cities and farms on streams, rivers, and lakes • Draining wetlands for agriculture & development