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Aquatic Biomes

Marine Biomeoceans cover 70% of earth's surface

Freshwater Biomelakes, ponds, rivers, streams cover only a small fraction

Ocean: essentially continuous and fairly stable

Most important features:*light and substrate

ALSO: salinity, tides, pressure((Salinity :Oceans: 35 parts per thousand

Freshwater: < 0.5 parts per thousand)

Marine Communities

Vertical Zonation based on light:

Photic Zone (Euphotic zone):sunlight , penetration increases from coastal waters (~30 meters) b/c of organisms and suspended particles to open ocean (~100+ meters)

** Zone where photosynthesis occurs **

Vertical Zonation based on light:

Aphotic Zone: below photic zone, organisms obtain energy by consuming organic material produced in the photic zone

Ocean ZonesOcean ZonesHigh tide

Low tideCoastal zone

EstuarineZone Continental

shelf

Open SeaSea level

Sun

Euphotic Zone

Bathyal Zone

Abyssal ZoneSlope

Continental

Depth inmeters

0

50

100

200 Phot

osyn

thes

is

500

1,000

1,500

2,000

3,000

4,000

5,000

10,000

Dar

knes

s

Fig. 7.5, p. 156

Aphotic zone

Photic zone

Classification based on bathymetry•Intertidal (Littoral) Zone: where sea meets land, really an ecotone between land and ocean

•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)

SFSU Geography 316-Fall 2006 Dr. Barbara A. Holzman

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Intertidal (Littoral) Intertidal (Littoral) where sea meets land, really an ecotone between land and ocean.

Intertidal: Littoral ZoneIntertidal: Littoral Zone

Neritic (Sublittoral) Neritic (Sublittoral) Zone Zone : beyond intertidal zone, few meters to ~200m deep

Neritic (Sublittoral) ZoneNeritic (Sublittoral) Zone

Neritic ZoneNeritic Zone beyond intertidal zone, few meters to ~200m deep Bathyal Zone: edges of

continental shelf

SFSU Geography 316-Fall 2006 Dr. Barbara A. Holzman

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Abyssal Zone: Abyssal Zone: most of the ocean, deep waters (2000-6000m in depth)

Organisms are also classified:

Benthic or Pelagic (oceanic): Association with substrate or water column

Benthic:hard substrates: kelp forests, coral reefs

vs.

soft muddy substrate: burrowing organisms beneath surface

Pelagic (Oceanic):

Plankton: microscopic organisms that float in water column –simple plants: phytoplanktontiny animals: zooplankton

Nekton: comprises the actively swimming animals, i.e. fish, whales, large invertebrates (higher trophic levels)

Phytoplankton

Zooplankton

PLANKTON

SFSU Geography 316-Fall 2006 Dr. Barbara A. Holzman

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Hogfish

Cobia

Pacific sailfish

Yellow jack

Batfish

MorayRed snapper

Striped drum Angelfish

Orange roughyChinook salmon

DevilfishGreat barracuda Porcupine

fish

Grouper

Chilean sea bass

Sockeye salmon

Nekton

Nekton or Plankton ? Coral ReefsCoral ReefsGray reef shark

Green seaturtle

Sea nettle

Fairy basslet

Bluetangs

Brittle starBanded coral

shrimp

Sergeant major

Parrot fish

Hard corals

Algae

Phytoplankton

Symbioticalgae

Zooplankton

Sponges

Bacteria

Morayeel

Black basslet

Coney

ProducerProducerto primaryto primaryconsumerconsumer

PrimaryPrimaryto secondaryto secondaryconsumerconsumer

Secondary to Secondary to higherhigher--levellevelconsumerconsumer

All consumer and All consumer and producers toproducers todecomposersdecomposers

Fig. 7.13, p. 163

Estuaries,salt marshes, swamps

SFSU Geography 316-Fall 2006 Dr. Barbara A. Holzman

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Freshwater BiomesFreshwater Biomes

Standing water (Lentic)

Flowing water (Lotic)

Sunlight

PaintedturtleGreen

frog

Pondsnail

Blue-wingedteal

Muskrat

Plankton

Northernpike

BloodwormsYellowperch

Divingbeetle

Littoral zone

Limnetic zone

Profundal zone

Benthic zone

Lotic: Running water Rapids zone Pool zones

Lentic: Littoral zone: shallow water where light penetrates to the bottom (vegetation)

Lakes Eutrophic: lakes are

shallow-highly productive b/c light penetrates almost to the bottom, good vertical circulation

Oligotrophic: lakes usually so deep that little to no vertical circulation occurs, limited nutrients and limited sunlight restricts primary productivity

Types of Lakes: EutrophicTypes of Lakes: Eutrophic

Sunlight

Much shorevegetationMuch shorevegetation

High concentrationof nutrition and plankton

Widelittoralzone

Limnetic zone Dense fish population

Gently slopingshorelinesSalt, sand,

clay bottomEutrophic Lake

SFSU Geography 316-Fall 2006 Dr. Barbara A. Holzman

For the exclusive use of students enrolled in GEOG 316 Fall 2006 SFSU

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Types of Lakes: OligotrophicTypes of Lakes: Oligotrophic

Sunlight

Limnetic zone

Profundal zone

Sand, gravel,rock bottom

Oligotrophic Lake

Sparce fish population

Low concentration ofnutrition and plankton

Narrowlittoralzone

Steeplyslopingshorelines

Little shorevegetation

Lake Tahoe

Other aquatic communitiesHypersaline lakes Caves

Geysers/Hot springsGeysers/Hot springs Human ImpactsHuman Impacts

•• Coral Reef Coral Reef DestructionDestruction

•• Loss of BiodiversityLoss of Biodiversity•• PollutionPollution•• DumpingDumping

SFSU Geography 316-Fall 2006 Dr. Barbara A. Holzman

For the exclusive use of students enrolled in GEOG 316 Fall 2006 SFSU

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Competition?Competition?

SFSU Geography 316-Fall 2006 Dr. Barbara A. Holzman

For the exclusive use of students enrolled in GEOG 316 Fall 2006 SFSU