Aquatic Biodiversity

1
Chapter 8

• Aquatic Biodiversity

2
Natural Capital Major Life Zones and Vertical
Zones in an Ocean
3
Fig. 6-1a, p. 126
4
Core Case StudyWhy Should We Care About Coral
Reefs?

• Coral reefs form in clear, warm coastal waters of
  the tropics and subtropics.
• Formed by massive colonies of polyps.

Figure 8-1
5
Core Case StudyWhy Should We Care About Coral
Reefs?

• Help moderate atmospheric temperature by removing
  CO2 from the atmosphere.
• Act as natural barriers that help protect 14 of
  the worlds coastlines from erosion by battering
  waves and storms.
• Provide habitats for a variety of marine
  organisms.

6
Fig. 6-7b, p. 131
7
Estuaries and Coastal Wetlands Centers of
Productivity

• Estuaries provide ecological and economic
  services.
• Filter toxic pollutants, excess plant nutrients,
  sediments, and other pollutants.
• Reduce storm damage by absorbing waves and
  storing excess water produced by storms and
  tsunamis.
• Provide food, habitats and nursery sites for many
  aquatic species.

8
y
Herring gulls
Peregrine falcon
Snowy Egret
Cordgrass
Short-billed Dowitcher
Marsh Periwinkle
Phytoplankton
Smelt
Zooplankton and small crustaceans
Soft-shelled clam
Clamworm
Bacteria
All consumers and producers to decomposers
Producer to primary consumer
Secondary to higher-level consumer
Primary to secondary consumer
Fig. 8-7
9
Case StudyDams, Wetlands, Hurricanes, and New
Orleans

• Dams and levees have been built to control water
  flows in New Orleans.
• Reduction in natural flow has destroyed natural
  wetlands.
• Causes city to lie below sea-level (up to 3
  meters).
• Global sea levels have risen almost 0.3 meters
  since 1900.

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Mangrove Forests
Figure 6-8
11
What Kinds of Organisms Live in Aquatic Life
Zones?

• Aquatic systems contain floating, drifting,
  swimming, bottom-dwelling, and decomposer
  organisms.
• Plankton important group of weakly swimming,
  free-floating biota.
• Phytoplankton (plant), Zooplankton (animal),
  Ultraplankton (photosynthetic bacteria)
• Necton fish, turtles, whales.
• Benthos bottom dwellers (barnacles, oysters).
• Decomposers breakdown organic compounds (mostly
  bacteria).

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Rocky and Sandy Shores Living with the Tides

• Organisms in intertidal zone develop specialized
  niches to deal with daily changes in
• Wave action

Figure 8-9
13
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

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Freshwater Life Zones
Fig. 8-15
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Types of Lakes Oligotrophic
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Types of Lakes Eutrophic
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Effects of Plant Nutrients on LakesToo Much of
a Good Thing

• Plant nutrients from a lakes environment affect
  the types and numbers of organisms it can support.

Figure 8-16
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River Systems

• Runoff

• Drainage basin

• Watershed

• Floodplain

Rain and snow
Source area
Source Zone
Fig. 8-17
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Rachel Carson

• All at last returns to the sea-to Oceanus, the
  ocean river, like the ever-flowing stream of
  time, the beginning and the end.
• End chapter 8