Oceans Flashcards
Where are coral reefs concentrated
The central indo-Pacific
What is the biology of corals
Colonial animal
Polyps are Symbiotic with algae (zooxqnthellae)
What give corals there colour
Algae and without it they would be clear. Also gives energy
What percentage of all marine species do coral reefs host
25% recent estimates suggest 33%
Why are coral reefs most diverse ecosystem on earth for vertebrates (hyperdiverse)
Complex reef structure with refuge holes and caves and complexity for lots of other animals to life within.
For fish, coral grows with different size holes to live in and provides niche for water flows and light intensity.
What percentage of all ocean area is corals
0.1%
How much do coral reefs contribute exostatems worth
$9.9 trillion eac year
What are the theee main values of coral reefs
Fisheries particularly subsidence and local ones.
Shoreline protection as the coral habitat dissipates energy.
Tourism.
Also property prices bc of health benefits of being near environment
What 3 interactions are there in coral reefs
Predation
Competition
Mutualism
What percentage coral cover is healthy coral
40%. Benthos should be made of algae and soft coral
What 6 threats to coral reefs cause them to decline globally
Nutrient enrichment Over fishing Aquarium trade Crowns of thorns starfish outbreak Dredging for coal ports Increasing cyuclone intensity
How does nutrient enrichment cause decline in corals
Excess nitrogen favours algae growth not coral so algae competing with coral for space become more successful when loads of nutrients are added
How does aquarium trade cause decline of coral
Some species are harvested in high numbers
How are COTs outbreak causing decline of coral
They feed on live coral and periodically you can get huge outbreaks in their numbers. Probably bc of nutrient enrichment their larvae can survive
What percentage of coral cover can COT larvae strip
9%
What is are global climate right now
405ppm
What is coral bleaching
A stress response where corals lose their symbiotic algae
How do corals gain energy
Photosynthesis of their symbiotic algae
Catching plankton in the water column with their tentacles 🦑
What percentage of corals energy comes from algae
90%
How do corals and their symbiotic algae engage in mutualism
The algae photosynthesis in coral and give it energy.
Coral provides somewhere for algae to live.
Adaption tO nutrient poor conditions.
Why did the symbiotic relationship between coral and algae think to evolve
Bc corals living in nutrient poor oligotrophic enguments ao croaks are building incredibly productive ecosystems besides being nutrient poor . The algae brings energy and nutrients through photosynthesis.
What happens during bleaching
Symbionts reduced by 60-90% in days
Loss of tissue biomass
Coral skeleton visible through transparent tissue
Density of single celled algae living in tissue reduces bc coral can’t feed.
Why are the calcium carbonate skeletons of coral visbible in bleaching
Bc the colour is gone due to algae dispersal
What do corals secrete
Photoprotective fluorescent proteins that can reflect and dissipate UV light