Why are Oceans essential?
Why are Oceans essential?
- Help to regulate atmosphere
- Transport and trade
- For food-fish-fishermen make money
- Energy-hydroelectric/wave power/tidal power
- Important for tourist industry-to earn money
- Natural resources
- Provide water cycle
- Scientific and educational research
- For fun!
- Oceans provide habitats for lots of species-food chain
- Coral is limestone rock made up of skeletons of tiny marine organisms called polyps.
- Coral reefs are found near the surface of the water because they need to have access to sunlight and they need warmth.
- Coral reefs are found around the equator in particular around the coast of Indonesia and North Australia
- The reefs are normally inbetween the two tropics, cancer and capricorn
Value of Coral Reefs
Tourism-magnet for world's tourists
Exploitation for fishing- 4000 species of fish provide food. 25% of the worlds fish comes from coral reefs.
Shoreline protection- protection from storms, tsunamis and wave erosion
Aquarium trades-supply tropical fish
Other uses-medicine, jewellery, building materials
Education and Research- learn about marine life
Great Barrier Reef
- Over 1500 species of fish live on the Great Barrier Reef, representing 10% of world fish species
- This reef supports a wide diversity of life, and was selected as a World Heritage Site in 1981
- The reef is located in the Coral sea, off the coast of Queensland in northeast Australia.
Problems for Oceans
- Climate change- global warming + rising sea levels
- Oil spils-damage and kill wildlife and destroy marine species
- Overfishing- food chains affected- can lead to extinction
- Pollution from coastline and tourism-litter and water pollution
- Tourist activities-may damage habitats (eg. coral reef)- tourism in decline
- millions of tons of plastic waste in the ocean
- wildlife poisoned
- 300million tons of new plastic made every year -(10% recycled)
- food chains are contaminated and food is dangerous
- toxins- DVT's and PCB's
- huge trawls collect waste at the bottom of oceans
- converting plastic waste into fuel
- Growing trade in reef fish
- Higher want (need) for exotic fish-luxury
- Most exotic fish goes to Hong Kong- 30,000 tons of fish a year!
- Loss of entire species and habitat
- Fish are taken at a juvenille age
- Tokyo-biggest fish market in the world
- A lot of rare bluefin tuna
- Nearly 50% of Japans food is from the sea
- Species at risk
- BUT helps the economy (money)
Blast Fishing in Philipenes
- Reefs-natural wonders of the world
- Use poison- stun fish -chemicals- kills fish and damages humans
- Dynamite- stun fish and make easier to catch- destroys coral reefs
- Hit rocks on the bottom to force fish into nets- wipes out whole reefs clear of fish
- provide jobs
- take pressure off the reefs
- old enough fish are caught
- Rise in sea levels- 9mm per year!
- 80% of ground only 1meter above sea level
- Could be flooded before 2100
- Reclaimed land
- Building new islands
- Building sea walls
The EU tries to manage overfishing by setting out quotas.
Quotas set out what can be caught and how much of it can be caught in certain areas
Countries divide the quotas between them
Where stocks of species have collapsed, fishing in that zone is banned.
The disadvantage of quotas is that 'waste fish' (fish that are not the right species) get thrown back into the water, dying or dead.