Aquatic Biodiversity

1
Aquatic Biodiversity

• Chapter 8

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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

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A Healthy Coral Reef in the Red Sea
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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
  earths 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.

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Most of the Earth Is Covered with Water (1)

• Saltwater global ocean divided into 4 areas
• Atlantic
• Pacific
• Arctic
• Indian
• Freshwater

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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

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The Ocean Planet
9
Ocean hemisphere
Landocean hemisphere
Fig. 8-2, p. 163
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Distribution of the Worlds Major Saltwater and
Freshwater Sources
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Most Aquatic Species Live in Top, Middle, or
Bottom Layers of Water (1)

• Plankton
• Phytoplankton
• Zooplankton
• Ultraplankton
• Nekton
• Benthos
• Decomposers

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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

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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.

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Oceans Provide Important Ecological and Economic
Resources

• Reservoirs of diversity in three major life zones
• Coastal zone
• Usually high NPP
• Open sea
• Ocean bottom

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Major Ecological and Economic Services Provided
by Marine Systems
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NATURAL CAPITAL
Marine Ecosystems
Economic Services
Ecological 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
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Natural Capital Major Life Zones and Vertical
Zones in an Ocean
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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
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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

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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

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View of an Estuary from Space
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Some Components and Interactions in a Salt Marsh
Ecosystem in a Temperate Area
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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
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Fig. 8-7b, p. 167
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Mangrove Forest in Daintree National Park in
Queensland, Australia
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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

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Living between the Tides
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Hermit crab
Sea star
Shore crab
High tide
Periwinkle
Sea urchin
Anemone
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
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Stepped Art
Fig. 8-9, p. 169
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Primary and Secondary Dunes
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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
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Coral Reefs Are Amazing Centers of Biodiversity

• Marine equivalent of tropical rain forests
• Habitats for one-fourth of all marine species

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Natural Capital Some Components and Interactions
in a Coral Reef Ecosystem
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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
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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

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Animation Ocean provinces
37
Video Elephant seals
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Video Florida reefs
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Video Giant clam
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Video Reef fish (Bahamas)
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Video Schooling fish
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Video Sea anemones
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Video Sea lions
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Video Sting rays
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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.

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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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Case Study The Chesapeake Bayan 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

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Case Study The Chesapeake Bayan Estuary in
Trouble (2)

• Overfishing
• 1983 Chesapeake Bay Program
• Update on recovery of the Bay
• Should we introduce an Asian oyster?

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Chesapeake Bay
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Video ABC News Beach pollution
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8-4 Why Are Freshwater Ecosystems Important?

• Concept 8-4 Freshwater ecosystems provide major
  ecological and economic services and are
  irreplaceable reservoirs of biodiversity.

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Water Stands in Some Freshwater Systems and Flows
in Others (1)

• Standing (lentic) bodies of freshwater
• Lakes
• Ponds
• Inland wetlands
• Flowing (lotic) systems of freshwater
• Streams
• Rivers

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Water Stands in Some Freshwater Systems and Flows
in Others (2)

• Formation of lakes
• Four zones based on depth and distance from shore
• Littoral zone
• Limnetic zone
• Profundal zone
• Benthic zone

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Major Ecological and Economic Services Provided
by Freshwater Systems
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NATURAL CAPITAL
Freshwater Systems
Ecological Services
Economic Services
Climate moderation
Food
Nutrient cycling
Drinking water
Waste treatment
Irrigation water
Flood control
Hydroelectricity
Groundwater recharge
Transportation corridors
Habitats for many species
Genetic resources and biodiversity
Recreation
Employment
Scientific information
Fig. 8-14, p. 174
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Distinct Zones of Life in a Fairly Deep Temperate
Zone Lake
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Sunlight
Blue-winged teal
Painted turtle
Green frog
Muskrat
Pond snail
Littoral zone
Plankton
Limnetic zone
Profundal zone
Diving beetle
Northern pike
Benthic zone
Yellow perch
Bloodworms
Fig. 8-15, p. 175
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Some Lakes Have More Nutrients Than Others

• Oligotrophic lakes
• Low levels of nutrients and low NPP
• Eutrophic lakes
• High levels of nutrients and high NPP
• Mesotrophic lakes
• Cultural eutrophication leads to hypereutrophic
  lakes

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The Effect of Nutrient Enrichment on a Lake
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Stepped Art
Fig. 8-16a, p. 175
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Freshwater Streams and Rivers Carry Water from
the Mountains to the Oceans

• Surface water
• Runoff
• Watershed, drainage basin
• Three aquatic life zones
• Source zone
• Transition zone
• Floodplain zone

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Three Zones in the Downhill Flow of Water
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Lake
Rain and snow
Glacier
Rapids
Waterfall
Tributary
Flood plain
Oxbow lake
Salt marsh
Deposited sediment
Delta
Ocean
Source Zone
Transition Zone
Water
Sediment
Floodplain Zone
Fig. 8-17, p. 176
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Stepped Art
Fig. 8-17, p. 176
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Case Study Dams, Deltas, Wetlands, Hurricanes,
and New Orleans

• Coastal deltas, mangrove forests, and coastal
  wetlands natural protection against storms
• Dams and levees reduce sediments in deltas
  significance?
• New Orleans, Louisiana, and Hurricane Katrina
  August 29, 2005
• Global warming, sea rise, and New Orleans

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New Orleans, Louisiana, (U.S.) and Hurricane
Katrina
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Projection of New Orleans if the Sea Level Rises
0.9 Meter
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Freshwater Inland Wetlands Are Vital Sponges (1)

• Marshes
• Swamps
• Prairie potholes
• Floodplains
• Arctic tundra in summer

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Freshwater Inland Wetlands Are Vital Sponges (2)

• Provide free ecological and economic services
• Filter and degrade toxic wastes
• Reduce flooding and erosion
• Help to replenish streams and recharge
  groundwater aquifers
• Biodiversity
• Food and timber
• Recreation areas

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Active Figure Lake zonation
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Animation Lake turnover
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Animation Trophic natures of lakes
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Video River flyover
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8-5 How Have Human Activities Affected Freshwater
Ecosystems?

• Concept 8-5 Human activities threaten
  biodiversity and disrupt ecological and economic
  services provided by freshwater lakes, rivers,
  and wetlands.

75
Human Activities Are Disrupting and Degrading
Freshwater Systems

• Impact of dams and canals on rivers
• Impact of flood control levees and dikes along
  rivers
• Impact of pollutants from cities and farms on
  rivers
• Impact of drained wetlands

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Case Study Inland Wetland Losses in the United
States

• Loss of wetlands has led to
• Increased flood and drought damage
• Lost due to
• Growing crops
• Mining
• Forestry
• Oil and gas extraction
• Building highways
• Urban development