Coral Reefs: Global Reefs

Question 1

Coral Bleaching

Answer 1

Caused by warm temperatures
Associated with widespread coral mortality
The temperature threshold is ~31 degrees
Hard coral mortality varies widely but ~50% as a rule of thumb
Susceptibility varies significantly by species and other individual variables, including size and previous exposure
Bleaching varies by species and morphotypes
Higher mortality for larger size and branching

Question 2

Temperature Stress Demographic Effects

Answer 2

This causes a change in fecundity

And demography of the community

Question 3

Ocean Acidification

Answer 3

Dissolving CO2 into seawater
Forming disassociated carbonic acid
Increase H+, lowering pH
Perhaps more important on a decadal scale
Lower pH leads to lower availability of carbonate ions for calcifying organisms