Management of Coral Reefs (SL IB Geography)

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

 

Formation of three coral reef structures

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 

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

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