6.7.B Ocean Acidification

Question 1

Ocean Acidification

Answer 1

-acidic ocean ecosystem has a lower concentration of carbonate ions, limiting the ability of marine life to create calcium-based structures.
-How it works;
1)ocean absorbs CO2 from the atmosphere
2)absorbed CO2 breaks down to form carbonic acid and hydrogen ions
3)free hydrogen ions bond with available carbonate ions to form bicarbonate, reducing the concentration of carbonate ions
4)carbonate ions are required by marine life to build and maintain calcium based structures such as shells and coral.

Question 2

Coral reefs;

Answer 2

-most important role of algae is to provide food to the coral through the carbohydrates produced during photosynthesis
-coral has narrow temperature range within which it can live; 23-29 degrees C
-if water becomes too warm, then coral bleaching will occur
-if CO2 emissions continue to rise, the pH of the ocean surface could be lowered to 7.8 by 2100. Corals stop growing when pH is less than this.
-If corals are destroyed, we will lose vital ecosystem services that they provide. Examples;
—- shelter 25% of marine species
—- support fishing industries
—- protect shorelines