Marine intertidal zones lecture

Question 1

intertidal zone

Answer 1

the area between the mean low tide and the mean high tide

Question 2

subtidal zone

Answer 2

the area that is always submerged

Question 3

Epifauna

Answer 3

organisms that live on the surface of the substrate

Question 4

infauna

Answer 4

organisms that live in the substrate

Question 5

meiofauna

Answer 5

organisms that are so small that they live between the grains of soft substrate

Question 6

problems associated with the intertidal zone

Answer 6

• desiccation
• temperature changes
• salinity changes
• interrupted feeding
• wave action and tides
• oxygen availability and build-up of CO2
• limited space

Question 7

organisms avoid dessication by

Answer 7

hiding, clamming up

Question 8

normal ocean salinity vs estuarine salinity

Answer 8

33-35 ppt - normal
5 - 30 ppt- estuarine
organisms in the intertidal zone are normally euryhaline (can tolerate a wide range of salinities) while subtidal organisms are normally stenohaline

Question 9

zonation in the intertidal

Answer 9

consists of upper intertidal (most exposed) to middle and lower intertidal (least exposed)

Question 10

upper vs lower intertidal zone

Answer 10

more competition and more species rich because of the less severe environment

Question 11

what form form the basis for the soft bottom communities food web?

Answer 11

detritus, photoautotrophs, and chemoautotrophs

Question 12

what form the basis for the rocky intertidal communities food web?

Answer 12

autotrophs such as seagrasses, algae, and diatoms.