Coral Reefs

Question 1

What is a coral reef ?

Answer 1

A coral reef is an underwater structure made from calcium carbonate that has been secreted ( given off ) by coral polyps ( tiny anemone- like animals ) , and they have developed over 1000s of years.

Question 2

How are coral reefs formed ?

Answer 2

Firstly coral polyps ( tiny anemone like animals ) absorb calcium carbonate from the ocean and then secrete ( give off ) the calcium carbonate to form limestone skeletons. Over time ( 1000s of years ) as more polyps create more limestone skeletons , these skeletons come together to form coral reefs.

Question 3

Where are coral reefs distributed and why ?

Answer 3

Coral reefs are distributed between the tropic of cancer and the Tropic of Capricorn. This is because they need to be in warm water because they only grow in warm temperatures. And also because coral reefs need lots of sunlight to be able to carry out photosynthesis.

Question 4

Name the characteristics necessary for coral reefs.

Answer 4

1. Coral reefs need to be in shallow water because they need to be able to absorb sunlight for the algae to carry out photosynthesis - hence they are only located at coasts or around islands
2. They need lots of sunlight to be able to carry out photosynthesis - hence they are located on the tropic regions
3. They need to be in clear water for the sunlight to be able to penetrate. Also because the water cant be polluted as they would die due to the unnecessary waste
4. They need to be in warm water because they only grow in warm temperatures - hence they are located in the tropic regions

Question 5

What are the advantages / benefits of coral reefs ?

Answer 5

Marine Species : Coral reefs support about 25% of all marine life in the ocean. This is because coral reefs are the habitats of some marine species and because they hide in coral reefs to stay safe from predators.

Global Economy: Coral reefs contribute billions of dollars annually to the global economy. This is because coral reefs provide tons of people with fish and seafood which they then sell. Also because coral reefs attract many tourists for activities like snorkeling and diving.

Coral reefs absorb wave energy. This reduces the force of tsunamis , storm surges and erosion caused by high tide ( maybe hurricanes ). Therefore, the impact of these natural hazards is less destructive and less severe.

Question 6

What are the threats coral reefs are currently facing ?

Answer 6

Ocean acidification : Ocean acidification occurs when the ocean absorbs too much carbon dioxide from the air , so it makes the water more acidic . In acidic water , there is less availability of carbonate ions (calcium carbonate) so it is harder for coral reefs to create limestone skeletons and grow / form.

Pollution : Pollution affects coral reefs negatively because the plastics physically damage the coral reefs and stop it from growing.