Geography 316.01 Dr. B.A. Holzman SFSU @2005
Aquatic Biomes
Marine Communities
Ocean: essentially continuous and
fairly stable
Marine Biome
Most important features:
*light and substrate
oceans cover 70% of earth's surface
Freshwater Biome
ALSO: salinity, tides, pressure
(Salinity :Oceans: 35 parts per thousand
Freshwater: < 0.5 parts per thousand)
lakes, ponds, rivers, streams cover
only a small fraction
increases from coastal waters (~30
meters) b/c of organisms and
suspended particles to open ocean
(~100+ meters)
** Zone where photosynthesis occurs **
• Aphotic Zone: below photic zone,
organisms obtain energy by consuming
organic material produced in the photic
zone
High tide
Low tide
Coastal zone
Sun
Open Sea
Sea level
Depth in
meters
0
50
Euphotic Zone
Estuarine
Zone
100
Continental
shelf
200
Photosynthesis
• Photic Zone: sunlight , penetration
Ocean Zones
500
Bathyal Zone
Continental
1,000
1,500
Slope
Abyssal Zone
2,000
3,000
4,000
Darkness
Vertical Zonation based on light
5,000
10,000
Fig. 7.5, p. 156
Classification based on bathymetry
•Intertidal (Littoral) Zone: where sea meets
land, really an ecotone between land and ocean
Intertidal (Littoral)
•Neritic (Sublittoral) Zone: beyond intertidal
zone, few meters to ~200m deep
•Bathyal Zone: edges of continental shelf
•Abyssal Zone: most of the ocean, deep waters
(2000-6000m in depth)
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Geography 316.01 Dr. B.A. Holzman SFSU @2005
Intertidal: Littoral Zone
Neritic (Sublittoral)
Sublittoral) Zone
Neritic
(Sublittoral)
Sublittoral) Zone
Neritic Zone
Bathyal Zone
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Geography 316.01 Dr. B.A. Holzman SFSU @2005
Bathyal Zone
Organisms are also classified:
Benthic or Pelagic (oceanic):
Association with substrate or
water column
Abyssal Zone
Benthic:
hard substrates: kelp forests,
coral reefs
vs.
soft muddy substrate: burrowing
organisms beneath surface
Pelagic (Oceanic):
Zooplankton
Plankton: microscopic organisms that
float in water column –
simple plants: phytoplankton
tiny animals: zooplankton
Nekton: comprises the actively
swimming animals, i.e. fish, whales,
large invertebrates (higher trophic
levels)
Phytoplankton
PLANKTON
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Geography 316.01 Dr. B.A. Holzman SFSU @2005
Pacific sailfish
Cobia
Hogfish
Moray
Red snapper
Yellow jack
Batfish
Striped drum
Angelfish
Orange roughy
Chinook salmon
Porcupine
fish
Great barracuda
Sockeye salmon
Grouper
Devilfish
Nekton
Chilean sea bass
Nekton or Plankton ?
Coral Reefs
Gray reef shark
Sea
nettle
Green sea
turtle
Fairy
basslet
Blue
tangs
Parrot
fish
Producer
to primary
consumer
Primary
to secondary
consumer
Sergeant
major
Hard
corals
Algae
Brittle star
Banded coral
shrimp
Phytoplankton
Symbiotic
algae
Coney
Zooplankton
Secondary to
higherhigher-level
consumer
Black basslet
Sponges
Moray
eel
Bacteria
All consumer and
producers to
decomposers
Fig. 7.13, p. 163
Estuaries,
salt marshes,
swamps
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Geography 316.01 Dr. B.A. Holzman SFSU @2005
Freshwater Biomes
Sunlight
Painted
turtle
Green
frog
Blue-winged
teal
Muskrat
Pond
snail
Littoral zone
Limnetic zone
Flowing water
(Lotic)
Diving
beetle
Plankton
Profundal zone
Benthic zone
Standing water (Lentic)
Yellow
perch
Northern
pike
Bloodworms
Lentic:
Littoral zone:
shallow water
where light
penetrates to
the bottom
(vegetation)
Lotic:
Running water
Rapids zone
Pool zones
Lakes
Types of Lakes: Eutrophic
Eutrophic: lakes are
Sunlight
shallow-highly
productive b/c light
penetrates almost to the
bottom, good vertical
circulation
Much shore
vegetation
Oligotrophic: lakes
usually so deep that little
to no vertical circulation
occurs, limited nutrients
and limited sunlight
restricts primary
productivity
High concentration
of nutrition and plankton
Limnetic zone
Salt, sand,
clay bottom
Wide
littoral
zone
Dense fish population
Gently sloping
shorelines
Eutrophic Lake
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Geography 316.01 Dr. B.A. Holzman SFSU @2005
Types of Lakes: Oligotrophic
Sunlight
Little shore
vegetation
Narrow
littoral
zone
Low concentration of
nutrition and plankton
Limnetic zone
Profundal zone
Sparce fish
population
Steeply
sloping
shorelines
Lake Tahoe
Sand, gravel,
rock bottom
Oligotrophic Lake
Other aquatic
communities
Hypersaline lakes
Caves
Geysers/Hot springs
Human Impacts
• Coral Reef
Destruction
• Loss of Biodiversity
• Pollution
• Dumping
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Geography 316.01 Dr. B.A. Holzman SFSU @2005
Competition?
Trouble in local waters
Farallon
Islands
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