benthos intertidal zone muddy bottom and sandy bottom communities salt marshes and seagrass beds...

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Page 2: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

BenthosBenthos

• Intertidal Zone• Muddy bottom and sandy bottom

communities• Salt marshes and seagrass beds• Coral reefs• Deep ocean benthos

Page 3: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Zonation is a vertical banding of the organisms living on the rocky coastline.

These distinct bands occur in part from many complex physical and biological factors that effect marine organisms.

Page 4: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos
Page 5: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Tidal Zones on a Rocky Ocean Shore

Splash Fringe Level

High Tide Level

Mid Tide Level

Low Tide Level

Low Fringe Level

Page 6: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Spray or Splash Zone

High Tide Zone

Middle Tide Zone

Low Tide Zone

Mostly shelled orgs

Many soft bodied orgs and algae

Page 7: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos
Page 8: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

opihi

Mussels & starfish

periwinkles

ulva

Page 9: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos
Page 10: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos
Page 11: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Biotic factors affecting organisms living in the intertidal zone:

• Competition for space and food• Predation• Reproduction• Substrate settlement preference• Osmoregulation

Page 12: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Abiotic factors affecting organisms living in the intertidal zone:• Salinity• Temperature • Air and light exposure• Tidal flow• Waves and current action• Substrate• Wind direction and strength• Dissolved O2• Storms• Natural Disasters

Page 13: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos
Page 14: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Orgs that live in the interstices of the sand

Infauna:  • live within the sediment, mostly soft bottom;  • mostly clams and worms (polychaetes)  • burrow tubes for food scavenging and oxygen supply

Page 15: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

32,000 polychaetes in sand/m2vs

50-500 earth worms in soil/m2

Ecological Role:• clean sediments • aerate soil

Page 16: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos
Page 17: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

• Found from the Arctic to Southern Australia

• Salt marshes grow in muds and sands that are sheltered by barrier islands.

• Flood and ebb currents transport saltwater, nutrients, plankton and sediments in and out of the marsh.

Page 18: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos
Page 19: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Species composition and zonation governed by: • Salinity gradient: river runoff, tides• Intertidal exposure

Low species diversity

Fiddler crab

Ribbed mussel

Page 20: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Salicornia

Distichles spicataFundulus heteroclitus

Page 21: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Found on all the main islands except Lanai

Hawaiian Stilt Hawaiian Coot

Found on all the main islands

Page 22: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Waikiki & Diamond HeadWaikiki & Diamond Head

1934

Page 23: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Ecological Importance:Act as a giant sponge:

• The salt marsh absorbs large volumes of water, thus minimizing the impacts of flooding and erosion and recharging groundwater.

• Salt marsh plants help purify water by absorbing toxins and in some cases metabolizing them into harmless substances.

• Most productive food factories on earth.

Page 24: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Of the original 215 million acres of wetlands in the U.S. (excluding Alaska and Hawaii) , about 106

million acres remain.

distribution of wetlands in the U.S. in the 1780s

distribution of wetlands in the U.S. in the 1900s

Page 25: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Current distribution of wetlands and deepwater habitats

Page 26: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

• Drainage • Dredging and stream channelization • Deposition of fill material • Diking and damming • Tilling for crop production • Levees • Logging • Mining • Construction • Runoff • Air and water pollutants • Changing nutrient levels • Releasing toxic chemicals • Introducing non-native species to the ecosystem • Grazing by domestic animals

Major Causes of Wetlands Loss and DegradationHuman Actions

Page 27: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Natural Threats

• Erosion

• Subsidence

• Sea level rise

• Droughts

• Hurricanes and other storms

Page 28: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Seagrass beds

Page 29: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Classification

Five kingdom system:

Monera Protista FungiPlantae Animalia

Angiosperms Gymnosperms

Page 30: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Distribution: 12 genera of seagrasses (5 in the high latitude and 7 in the low latitude)

• True marine angiosperm• Evolved from shoreline Lillie-like plants~100

mya• Vascular plants reinvaded the seas 3 different

times (algae is nonvascular; i.e., no need for roots to transport water and nutrients)

• Can grow and reproduce while completely submerged under water

Page 31: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Halophila hawaiiana- only form of seagrass in Hawaii

Page 32: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Develop in:• intertidal and shallow subtidal

areas on sands and muds• marine inlets and bays • lagoons and channels, which are

sheltered from significant wave action

Page 33: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

1. Help stabilize the sediment

2. Prevents resuspension of sediments in water (water is clearer)

3. Binds substratum, reduces turbidity, and reduces erosion

4. Sediment accumulation slows velocity of incoming water

5. Food for many organisms

6. Refuge for many organisms

Page 34: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Seagrass productivity is highly dependent on a number of factors:• salinity• water temperature• turbidity

This ecosystem is particularly sensitive to degradation due to:• agricultural pollution-run-off of

herbicides• industrial pollution• domestic pollution

Threats to Seagrass BedsThreats to Seagrass Beds

Page 35: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Coral Reef Communities

Page 36: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Hermatypic corals:• possess zooxanthellae• are reef builders

Light: Clear water Warm temperature: 18-32oCLow nutrientsLow productivity in water

Ahermatypic corals:• no zooxanthellae• rely on tentacular feeding• can live in aphotic zone

Page 37: Benthos Intertidal Zone Muddy bottom and sandy bottom communities Salt marshes and seagrass beds Coral reefs Deep ocean benthos

Cauliflower coral(Pocillopora meaandrina)

6 m

0 m

25 m

13 m

Lobe coral(Porites lobata)

Finger coral(Porites compressa)

Plate coral(Porites rus)

High light levelsModerate wave energy

Moderate light levelsOccasional storm wave energy

Low light levelsLow wave energy

Very low light, Primarily downwelling No wave energy