Coral Reef Distribution

Question 1

What is the distribution of coral reefs globally?

Answer 1

they are found in tropical and temperate waters. If they are shallow water, usually found between 30deg N and 30deg S up to 50m deep.

Question 2

what is the distribution of coral reefs across Australia?

Answer 2

East coast- GBR from Bunderberg to Cape York
North west/west Aus- Ninguloo Reef

Question 3

What abiotic factors have affected distribution of coral reefs over geological time?

Answer 3

dissolved oxygen
light availability (Low turbidity for photosynthesis)
stable salinity (35g/L)
temperature (19-30deg C)
suitable substrate
aragonite (stable pH 8.2)
low levels of nitrates and phosphates

Question 4

When did corals first appear within the geological record and when in Australian waters?

Answer 4

In geological record over 250 million years ago but only in Australian waters about 500’000 years ago

Question 5

What was the main factor that shaped the great Barrier Reef in it’s creation?

Answer 5

Changes in sea levels that began over 20 000 years before present (BP) and only stabilised 6500 years BP

Question 6

What are the different types of reef structures?

Answer 6

fringing
platform
ribbon
atolls
coral cays

Question 7

What are the 3 zonation areas of a reef cross-section?

Answer 7

Back reef/lagoon, reef crest/rim and the reef slope