Aquatic Biodiversity

1. Aquatic Biodiversity Chapter 8

2. Core Case Study: Why Should We Care about Coral Reefs? (1) • Biodiversity • Formation • Important ecological and economic services • Moderate atmospheric temperatures • Act as natural barriers protecting coasts from erosion • Provide habitats • Support fishing and tourism businesses • Provide jobs and building materials • Studied and enjoyed

3. Core Case Study: Why Should We Care about Coral Reefs? (2) • Degradation and decline • Coastal development • Pollution • Overfishing • Warmer ocean temperatures leading to coral bleaching • Increasing ocean acidity

4. A Healthy Coral Reef in the Red Sea

5. 8-1 What Is the General Nature of Aquatic Systems? • Concept 8-1A Saltwater and freshwater aquatic life zones cover almost three-fourths of the earth’s surface with oceans dominating the planet. • Concept 8-1B The key factors determining biodiversity in aquatic systems are temperature, dissolved oxygen content, availability of food and availability of light and nutrients necessary for photosynthesis.

6. Most of the Earth Is Covered with Water (1) • Saltwater: global ocean divided into 4 areas • Atlantic • Pacific • Arctic • Indian • Freshwater

7. Most of the Earth Is Covered with Water (2) • Aquatic life zones • Saltwater: marine • Oceans and estuaries • Coastlands and shorelines • Coral reefs • Mangrove forests • Freshwater • Lakes • Rivers and streams • Inland wetlands

8. The Ocean Planet

9. Ocean hemisphere Land–ocean hemisphere Fig. 8-2, p. 163

10. Distribution of the World’s Major Saltwater and Freshwater Sources

11. Most Aquatic Species Live in Top, Middle, or Bottom Layers of Water (1) • Plankton • Phytoplankton • Zooplankton • Ultraplankton • Nekton • Benthos • Decomposers

12. Most Aquatic Species Live in Top, Middle, or Bottom Layers of Water (2) • Key factors in the distribution of organisms • Temperature • Dissolved oxygen content • Availability of food • Availability of light and nutrients needed for photosynthesis in the euphotic, or photic, zone

13. 8-2 Why Are Marine Aquatic Systems Important? • Concept 8-2 Saltwater ecosystems are irreplaceable reservoirs of biodiversity and provide major ecological and economic services.

14. Oceans Provide Important Ecological and Economic Resources • Reservoirs of diversity in three major life zones • Coastal zone • Usually high NPP • Open sea • Ocean bottom

15. Major Ecological and Economic Services Provided by Marine Systems

16. NATURAL CAPITAL Marine Ecosystems Ecological Services Economic Services Climate moderation Food CO2 absorption Animal and pet feed Nutrient cycling Pharmaceuticals Waste treatment Harbors and transportation routes Reduced storm impact (mangroves, barrier islands, coastal wetlands) Coastal habitats for humans Recreation Habitats and nursery areas Employment Oil and natural gas Genetic resources and biodiversity Minerals Scientific information Building materials Fig. 8-4, p. 165

17. Natural Capital: Major Life Zones and Vertical Zones in an Ocean

18. High tide Sun Low tide Depth in meters Open Sea Coastal Zone Sea level 0 50 Photosynthesis Euphotic Zone Estuarine Zone 100 Continental shelf 200 500 Bathyal Zone Twilight 1,000 1,500 2,000 Abyssal Zone Water temperature drops rapidly between the euphotic zone and the abyssal zone in an area called the thermocline . 3,000 Darkness 4,000 5,000 10,000 0 5 10 15 20 25 30 Water temperature (°C) Fig. 8-5, p. 166

19. Estuaries and Coastal Wetlands Are Highly Productive (1) • Estuaries and coastal wetlands • River mouths • Inlets • Bays • Sounds • Salt marshes • Mangrove forests • Seagrass Beds • Support a variety of marine species • Stabilize shorelines • Reduce wave impact

20. Estuaries and Coastal Wetlands Are Highly Productive (2) • Important ecological and economic services • Coastal aquatic systems maintain water quality by filtering • Toxic pollutants • Excess plant nutrients • Sediments • Absorb other pollutants • Provide food, timber, fuelwood, and habitats • Reduce storm damage and coast erosion

21. View of an Estuary from Space

22. Some Components and Interactions in a Salt Marsh Ecosystem in a Temperate Area

23. Herring gulls Peregrine falcon Snowy egret Cordgrass Short-billed dowitcher Marsh periwinkle Phytoplankton Smelt Zooplankton and small crustaceans Soft-shelled clam Bacteria Clamworm Producer to primary consumer Secondary to higher-level consumer Primary to secondary consumer All consumers and producers to decomposers Fig. 8-7a, p. 167

24. Fig. 8-7b, p. 167

25. Mangrove Forest in Daintree National Park in Queensland, Australia

26. Rocky and Sandy Shores Host Different Types of Organisms • Intertidal zone • Rocky shores • Sandy shores: barrier beaches • Organism adaptations necessary to deal with daily salinity and moisture changes • Importance of sand dunes

27. Living between the Tides

28. Hermit crab Sea star Shore crab High tide Periwinkle Anemone Sea urchin Mussel Low tide Sculpin Barnacles Kelp Sea lettuce Monterey flatworm Rocky Shore Beach Beach flea Nudibranch Peanut worm Tiger beetle Blue crab Clam Dwarf olive High tide Sandpiper Ghost shrimp Low tide Silversides Mole shrimp Barrier Beach White sand macoma Sand dollar Moon snail Fig. 8-9, p. 169

29. Hermit crab Sea star Shore crab Rocky Shore Beach High tide Periwinkle Sea urchin Anemone Mussel Low tide Sculpin Barnacles Sea lettuce Kelp Beach flea Monterey flatworm Tiger beetle Peanut worm Nudibranch Barrier Beach Clam Blue crab Dwarf olive High tide Sandpiper Ghost shrimp Silversides Low tide Mole shrimp White sand macoma Sand dollar Moon snail Stepped Art Fig. 8-9, p. 169

30. Primary and Secondary Dunes

31. Ocean Beach Primary Dune Trough Secondary Dune Back Dune Bay or Lagoon Recreation, no building Walkways, no building Limited recreation and walkways Walkways, no building Most suitable for development Recreation Bay shore Grasses or shrubs Taller shrubs Taller shrubs and trees Fig. 8-10, p. 170

32. Coral Reefs Are Amazing Centers of Biodiversity • Marine equivalent of tropical rain forests • Habitats for one-fourth of all marine species

33. Natural Capital: Some Components and Interactions in a Coral Reef Ecosystem

34. Gray reef shark Sea nettle Green sea turtle Parrot fish Fairy basslet Blue tang Sergeant major Algae Brittle star Hard corals Banded coral shrimp Coney Phytoplankton Symbiotic algae Coney Zooplankton Blackcap basslet Sponges Moray eel Bacteria Producer to primary consumer Secondary to higher-level consumer Primary to secondary consumer All consumers and producers to decomposers Fig. 8-11, p. 171

35. The Open Sea and Ocean Floor Host a Variety of Species • Vertical zones of the open sea • Euphotic zone • Bathyal zone • Abyssal zone: receives marine snow • Deposit feeders • Filter feeders • Upwellings • Primary productivity and NPP

36. Animation: Ocean provinces

37. Video: Elephant seals

38. Video: Florida reefs

39. Video: Giant clam

40. Video: Reef fish (Bahamas)

41. Video: Schooling fish

42. Video: Sea anemones

43. Video: Sea lions

44. Video: Sting rays

45. 8-3 How Have Human Activities Affected Marine Ecosystems? • Concept 8-3 Human activities threaten aquatic biodiversity and disrupt ecological and economic services provided by saltwater systems.

46. Human Activities Are Disrupting and Degrading Marine Systems • Major threats to marine systems • Coastal development • Overfishing • Runoff of nonpoint source pollution • Point source pollution • Habitat destruction • Introduction of invasive species • Climate change from human activities • Pollution of coastal wetlands and estuaries

47. Case Study: The Chesapeake Bay—an Estuary in Trouble (1) • Largest estuary in the US; polluted since 1960 • Population increased • Point and nonpoint sources raised pollution • Phosphate and nitrate levels too high

48. Case Study: The Chesapeake Bay—an Estuary in Trouble (2) Overfishing 1983: Chesapeake Bay Program Update on recovery of the Bay Should we introduce an Asian oyster?

49. Chesapeake Bay

50. Video: ABC News: Beach pollution