Management of Coral Reefs (DP IB Geography)
Revision Note
Coral reef Characteristics
Characteristics of coral reefs
Coral reefs are productive environments
Warm coral reefs are located in tropical and subtropical waters (above 18°C)
Cold tropical reefs are located in deep, dark waters (4–12°C)
Coral reefs are also fragile environments
Any slight change in a coral reef environment can have devastating effects
Coral reefs form by small coral larvae (polyps) attaching themselves to rocks
Polyps secrete calcium carbonate, creating a hard skeleton. Other polyps can then connect to this skeleton
Polyps can divide (clone) themselves. These clones connect, forming a large organism
These organisms connect further over time, forming large coral reefs
There are three differing structures of a coral reef:
Fringing reefs
The most common form of coral reef
Exist close to coastlines, like a border
Barrier reefs
Barrier reefs also exist on coastlines, but a deep lagoon separates the shore and the reef
Can form as fringing reefs grow and connect with each other
Very rare forms of coral reef
Atoll reefs
As a volcanic island sinks beneath sea level and a fringing reef encircles it, atoll reefs form
They are circular shaped, with a lagoon in the middle
Found in the middle of the ocean
Formation of three coral reef structures
Coral Reefs Uses & Value
Uses and value of coral reefs
Coral reefs are valuable ecosystems
Stakeholders value and use coral reefs differently
Coral reefs are also dangerously under threat
All stakeholders must work together to reduce threats to coral reef environments
Coastal protection
Coral reefs reduce the impact of strong storm waves, helping to reduce the erosion of the coastline
They protect coastal landscapes (e.g. mangrove swamps) and local communities
Coral reefs are valuable to local residents and environmentalists
Resource use
Fish are abundant in coral reef environments. This provides food and livelihoods for local residents
Both commercial and subsistence fishing occur in coral reef environments
Coral reefs help to develop medicine. The biodiversity of reef systems provides treatments for diseases including cancer, asthma and other bacterial or viral diseases
Coral reefs are valuable to fishing industries and science development
Tourism and the economy
Coastal areas with coral reefs attract millions of tourists each year
Divers and beach lovers alike bring vital tourism to coastal areas
Coral reefs boost the economy by providing jobs and bringing tourism to the area
From accommodation to boat crews, income from tourism is important for coastal communities
Coral reefs are valuable to tourists and the tourist economy
Species habitat
Coral reefs are home to all types of species; they are incredibly biodiverse
From fish to mammals, coral reefs provide food, shelter and nursery for an estimated 25% of all marine life
Coral reefs are valuable to marine life and environmentalists
Threats
Development
Coastline development for commercial and non-commercial practices puts pressure on coral reefs
Activities like quarrying, dredging, boating practices and recreation can damage coral reefs
Overfishing and harvesting
Overfishing of coral reef environments can be disastrous for the food web
Coral reefs need fish to remove dangerous algae
Blast fishing can damage coral reefs’ structure
Harvesting coral reefs for the jewellery/souvenir industry can damage biodiversity and cause habitat destruction
Pollution
Increased sediment (from development, agriculture, deforestation etc.) can choke coral reefs
Coral reefs require very little nutrients to function. More nutrients enter the coral reef environment from fertilisers, sewage and animal waste
Algae growth increases with higher nutrient densities and uses vital oxygen and blocks sunlight
More harmful bacteria also grow with higher nutrient densities
Diseases enter coral reef environments from sewage, storm runoff and industrial and agricultural runoff
Rubbish and microplastics also damage coral reef ecosystems
Acidification and bleaching
Algae gives coral reefs their colour
As sea waters warm, coral reefs get rid of this algae, causing coral reefs to lose colour.
This is coral bleaching
This exposes the calcium carbonate and leaves corals under stress
As carbon dioxide in the atmosphere rises, so too do carbon dioxide levels in the ocean
Carbonic acid increases, resulting in ocean acidification
Examiner Tip
Think about which stakeholders would benefit from coral reefs. Why do environmentalists benefit? Why do local populations benefit?
Case Study: The Great Barrier Reef
The Great Barrier Reef, Australia
The Great Barrier Reef is the largest coral reef environment in the world
Located in the northeast of Australia, along the coastline of Queensland
It is over 1250 miles long
Location of the Great Barrier Reef
Threats
Climate change
Sea waters around the Great Barrier Reef are rising in temperature, resulting in coral bleaching
Fears of flooding and storm intensity are exacerbated by climate change
Runoff
Increased runoff from agriculture is a large issue
This increases nutrients, sediment and pesticides in the water
Development
Past, present and future development poses a threat to the reef
These are agriculture, mining, urbanisation, industrial development, port development, aquaculture and tourism development
Fishing and poaching
Overfishing
Illegal fishing
Incidental catch
Scale
The Great Barrier Reef is vast. It is difficult to find enough funding, resources and people to protect the area
Invasive species
Crown-of-thorns starfish
Lionfish
Management
World Heritage Site and a Natural Wonder of the World – this provides lawful protection and global recognition
Legislations
Created for The Great Barrier Reef area, Queensland, The Commonwealth, and the International level
Reef 2050 plan
Long-term plan for reef sustainability
Bringing together governments, local communities and industries
Assesses values and threats to the reef, guiding professionals to where management is most necessary
Education
Education and training is important for people like tour guides
Presentations on reef protection regularly show at the Marine Park Authority Office
Regular research is carried out to assess management strategies and their effectiveness
Universities in Queensland offer courses for coral research
Tools
Zoning plans
Guiding where activities and industry can and cannot take place
Includes ‘No Take Zones’, ‘Scientific Research Zones’, ‘Green Zones’ for recreation, and ‘General Use Zones’
Permits – most activities require a permit, e.g. tourism, infrastructure construction, boating
Policies – environmental, scientific and tourist government policies are set in place
Balancing stakeholders
Tourism management
Balancing the importance of tourism while protecting the reef
Guidance on managing reef tourism
Future plans for tourism to be ecological as well as respectful to the heritage of the area
Heritage management
Respecting Aboriginal ownership of land and knowledge of the area
Working with Aboriginals and Torres Strait Islanders to protect the reef together
Training, programs, mapping and action plans
Science management
Using scientific evidence to guide management practices
Monitoring
Fluker posts involve tourists in monitoring strategies
Tourists use these posts to take pictures of the reef
Photos are transferred to a site for professionals to examine
Cost-benefit – this saves money and time for workers
Species protection and control
Some species have different levels of protection (international, national, state or local)
This means they have lawful protection
Species are also separated into threatened, at-risk or iconic
Some species must be controlled due to their negative impact, such as crown-of-thorns starfish outbreaks
Professional divers inject starfish to kill them (without harming the environment)
Reef restoration
Planting vegetation in canals to reduce sediment
Coral IVF – growing baby corals outside of the reef and replacing them back into degrading areas
Coral fragments – taking fragments and planting them elsewhere (underwater or onshore in tanks)
Cryopreservation – freezing tissue in nitrogen for future preservation, reducing the risks of species extinction
Photogrammetry – monitoring the growth of the coral reef
Traditional management
Indigenous People are using traditional and modern tracking methods to track animals like turtles
There is a priority for subsistence fishing, limiting overfishing
Some areas of the reef are taboo, increasing protection
Some areas of the reef belong to Indigenous Groups
Last updated:
You've read 0 of your 10 free revision notes
Unlock more, it's free!
Did this page help you?