Coral reefs Flashcards
What temperature range does coral reefs require
23-25 degrees
What depth does coral reefs require
25 and less
What type of salinity does the coral reef require?
low salinity
What type of ph do corals require
PH of around 8.7
What type of tubidity do corals require
A low turbidity
Do corals require light
Yes, they need light for their algae to photosynthesise
Where do zooxanthellae live
They live in the polyp of the coral, the tissue of the coral
What happens when temperatures rise or conditions change (negatively)
The coral becomes stressed and expels its zooxanthellae. This is known as coral bleaching. If repeated this can cause the coral to die
What relationship do the coral and the alge have
A symbiotic realtionship
How does the algae benefit the coral
provides food for it
What is the value of coral reef tourism to australia
£6.4 billion each year
How does the coral benefit the algae
Provides it protection
What is el nino and how does it affect the coral
El Nino - El Nino is a event where sea temperatures rise 0.5 degrees above long term average. This event increases the sea temperature to a point where the coral becomes stressed, this causes the polyps to expel the algae. These tend to be mass bleaching events as it affects a large range of coral.
How does tourism effect coral reefs
Tourism - Tourism has affected the coral in many ways, when tourists touch the coral it can harm it. Furthermore, sun lotion can also damage the coral and by allowing tourists to swim around these areas the sun lotion is released into the sea water and directly effects the coral. Tourist boats also have an effect on the coral as the fuel emissions can leak into the water and cause damage to the coral. Provided around 6.5 million jobs and estimated to add 36 billion to economies each year. Fish feeding.
How does overfishing effect coral reefs
Overfishing - Netting and dynamite and forms of fishing and this leads to the destruction of the coral. Furthermore, fish and corals have a symbiotic relationship as corals act as a nursery for the fish and protect them from predators. If you damage the coral then fish stocks will subsequently decrease. This is done to sustain exports and fuel local economies though this is devastating to the coral. The fish stop algae from over growing and keeps the growth in check in return fr the nurseries and without this could limit the corals access to sunlight. Can effect the trophic
How does ocean acidity effect coral reefs
Ocean Acidity - As carbon dioxide emissions rise more of this carbon dioxide dissolves in the oceans, this causes acidity to increase. For the Zooxanthellae to survive the water to needs to be at a certain ph and by changing this PH the coral could become stressed and the algae would be expelled causing the coal to die. Corals loose the optimal conditions.
How does global warming effect coral reefs
Global Warming - As global temperatures increase due to increased carbon emissions from the burning of fossil fuels a cascade of effects bombard the coral. Firstly this causes sea levels to rise as the ice caps in the Antarctic melt into the oceans which increases the depth coral are below the surface which therefore means they have less access to sunlight which can again cause the coral to die. Furthermore it increase global sea temperatures every year, the higher these temperatures get the bigger the bleaching events are going to be till there is no coral next.
How does algal blooms effect coral reefs
Algal blooms - Algal blooms often occur from leaking of pollution into oceans that can feed the algae. Moreover over fishing can cause the loss of algae eating fish species which can allow for algae populations to explode. These algae can also cause more harmful microbes of the water as they feed of this algae. These microbes then endanger the corals as they respire and depleting oxygen supplies or by introducing diseases. This can cause the coral to die off
How does predation effect coral reefs
Predation - This is where predators for the coral feed of its soft inner tissue and can eventually lead to the destruction of the coral. One type of predator for the coral is parrot fish which have adapted to feed of the coral.
Hows does onshore development effect coral reefs
On shore development - Can cause increased levels of: Sedimentation, sewage effluent/leaking into water and other dangerous chemicals entering the water. Oil spills can widely effect the coral as it can damage reproduction and growth and kill fish species and their symbiotic relationship
How does drainage basins effect coral reefs
Drainage basins - Allows chemicals and loose soil to flow into the oceans which can increase the turbidity of the water and stress the corals. Causes sedimentation, this increases the turbidity of the water reducing the amount of sunlight that can reach the coral. This can cause the algae to die as it can not photosynthesise and therefore kill the coral. If antibiotics leak into the water from pharmaceuticals it can damage the protective mucus coating on the coral.
How does desalination effect coral reefs
Desalination - Can elevate salinity and release harmful chemicals used in the process. Therefore this would alter the optimal conditions of the coral and lead to it stressing.
How is the coral reef being managed (great barrier reef)
Reef Guardian school - educating kids about how to protect coral reefs, how they work etc. Over 350,000 students educated so far.
Been allocated as international heritage site by unessco
What are MPAs
Marine protected areas
How do MPAs help coral
don’t allow fishing which preserves biodiversity and limits the impact of tourism
WHy in practice do MPAs not work
As pollution in other areas can just enter the MPA and just affect the coral anyway. Cost a lot to police
How many people visit the Great Barrier Reef each year
over 2million people
How is the el nino event impacting the coral reef
causes 0.5 degree rise in temperature
How many river basins drain into the Great Barrier Reef
35
How much has sediment inflow increased into the catchment
10*
Who monitors the MPA in australia
MArine park authority
How many fish species are in the great barrier reef
over 1500
What is the COT
the crown of thrawns- they feed on the coral
How many jobs does the great barrier reef support
What locale scale management have they done inland
worked with farmers to prevent chemicals entering the draiange basins, such as the burdekin cane farmers
What locale scale monitoring is taking place at the reefs
coral watch - provide easy to use equipment to locals to measure coral health which can be uploaded online
How much coral in the great barrier reef has escaped bleaching
2% since 1998
