Intertidal Zone Outline

 Nicole Carneal, Sara Harper, and Brandon Schneider

 

 

I           The Intertidal Zone

A.                 Littoral Zone

B.                 Area between tides

II          Habitat

A.                 Rocky substrate

B.                 Characteristics

a.       Wave action

b.      Surf exposure

c.       Vertical zonation pattern

III        Zonation

A.                 Space is limiting resource

B.                 Distribution governed by:

a.       Competition for living space

b.      Need to find food

c.       Need to find shelter

d.      Avoidance of predators

e.       Desiccation

IV        The Zones

A.                 Splash Zone

a.       Uppermost zone

B.                 Upper Intertidal Zone

a.       Exposed to air daily

C.                 Middle Intertidal Zone

a.       Covered by higher low tides

D.                 Lower Intertidal Zone

a.       Mostly submerged

V         Causes of Zonation

A.        Physiological tolerance

·        Certain organism are susceptible to desiccation [drying out] and over heating

·        Other organisms need the low tide for food searching

B.         Larval and adult preference

•         According to the textbook, Larvae supplies depends n adults in the area, but the species depends on many larvae survive to adulthood.

C.        Competition

•         Prey will avoid settling in zones where the predators settle

D.        Predation

•         According to the text, Predation more effective in the low flow areas b/c when the tide is low prey is exposed to the world

VI        Ecological Signification

A.        Diversity

•         Natural selection will cause different organisms to reproduce in particular

•         According to the textbook, large water exchange= bring in more larval supply; low water exchange = less larval supply

B.         Macroalgal

•         Grow and produce organic material

•         Biomass supports the rocky intertidal habitat and soft-bottom dwellers

•         Die, become base of food chain

VII       Disturbances

A.        Low

•         Allows organisms to take over area

B.         Moderate

•         Allows different organisms to coexist

C.        Large

•         Liberated space

•         Allow inferior competitors to persist

D.        Wave shock

•         Constant wave crashes remove organisms that can not survive the waves

•         Allows space for new organisms to colon

E.         Predation

-         The Level of disturbances changes with the amount of predation area

-         Low predation = low disturbance

-         High predation = higher predation

F.         Natural disasters

•         Hurricanes and other storms

•         strip the rocks

•         Stirs up the water