Presentation on theme: "ARC 344 HUMAN IMPACTS ON CORAL REEFS Ertuğ Cemal BARUTOĞLU 1662550."— Presentation transcript:
ARC 344 HUMAN IMPACTS ON CORAL REEFS Ertuğ Cemal BARUTOĞLU
OUTLINE Importance of Coral Reefs Human Impacts on Coral Reefs –Sedimentation –Overfishing –Careless Recreation –Pollution –Climate Change Results of Impacts
Importance of Coral Reefs Corals are shelters for fishes Corals controls O 2 and CO 2 levels of sea Corals are natural barriers that protect nearby shorelines from the eroding forces of the sea, thereby protecting coastal dwellings, agricultural land and beaches. imatology_closeup_2.php
Importance of Coral Reefs With growth rates of 0.3 to 2 centimeters per year for massive corals, and up to 10 centimeters per year for branching corals, it can take up to 10,000 years for a coral reef to form from a group of larvae Depending on their size, barrier reefs and atolls can take from 100,000 to 30,000,000 years to fully form.
Human Impacts on Coral Reefs Climate Change Sedimentation Over-Fishing Careless Recreation Pollution
What is sedimentation? Sedimentation occurs when sediments found on land (soil, silt, & sand) enter the ocean and cause the water to become very murky Sedimentation
How does sediment travel? Sedimentation Wind Runoff Natural Impacts
What are human causes of sedimentation? Clearing land for homes, resorts, & other buildings Sedimentation Harbor construction Agriculture Dredging
How does sedimentation threaten the coral reef habitat? Smothering coral when particles settle out Reducing light availability which reduces coral photosynthesis and growth Sedimentation increases nutrients which allow algae overgrowth on coral Sedimentation
Over-fishing is when people take more fish from the ocean than the ocean can produce Smothering coral when particles settle out Reducing light availability which reduces coral photosynthesis and growth Sedimentation increases nutrients which allow algae overgrowth on coral Over-Fishing
How do people over-fish? Over-Fishing longlines dynamite & poisons gillnets
Over-fishing threatens the coral reef habitat Over-Fishing Fish caught too young cannot grow old to reproduce and contribute to fish population Fewer fish are available to provide food for other marine organisms Some fish eat algae and where there are less of these fish, algae grows too thick and smothers the reef
How do people use the reef for recreation? Careless Recreation snorkeling diving surfing boating fishing
How are people careless with the reef? Careless Recreation Kicking, touching, or standing on coral Boats can drop anchor or drive across shallow coral Abandoning fishing gear https://cabrillo.edu/~ncrane/Clipperton/clippertonlog8.html https://cabrillo.edu/~ncrane/Clipperton/clippertonlog8.html
What can you do to protect the reef? Careless Recreation Don’t touch the coral or any other animals Do not drive your boat over coral Only drop anchors in sand or other non-coral sediment Educate others!
Pollution Human’s cause many forms of pollution that harms or kills coral. Lost fishing gear (ghost gear) Raw sewageTrash that settles on coral will kill it Oil can kill all forms of sea life
Climate Change What is climate change? Climate change is the increase in the temperature of the Earth’s air and oceans.
What causes climate change? Climate Change happens when more carbon dioxide enters the atmosphere than can be removed by plants Climate Change
Human sources of climate change many types of transportation factories anything that uses fossil fuels! Climate Change deforestation Climate Change
How does climate change affect the coral reef habitat? Climate Change Bleaching is a result of warm sea-surface temperatures Increases in water temperature can kill marine organisms not adapted to the warmer temperatures healthy coralbleached coral Climate Change polynesia.html
Human Impacts on the Ocean The Big Picture
Results of Impacts Susceptible species die as a result of bleaching Significant declines occur in coral genetic and species diversity when corals die as a result of bleaching Change in the size structure of the reef fish populations and assemblages when corals die as a result of bleaching Bio-erosion and collapse of structural complexity of the reef will accelerate changes in reef communities, erosion of beaches, and loss of coral islands With the corals absent, fish and invertebrates that rely on the coral for food and habitat leave
Conclusion In conclusion, these behaviours of human cause bleaching and extinction of one of the most beautiful visual exhibitions in the world and the sea life accordingly. To prevent this extinction, people should be more awared and educated not only giving up from doing personal damage on them but also stopping the activities causing climate change like deforestation or air pollution.
References G. Hodgson, (1999), A global assessment of human effects on coral reefs. Marine Pollution Bulletin (vol. 38, pp ) B.S. Haplern, S. Walbridge, (2008), A global map of human impact on marine ecosystems (vol. 319, pp ) Nystrom, M., Falke, c., and Moberg, F. (2000). Coral reef disturbance and resilience in a human-dominated environment. Trends in Ecologly and Evolution 15, pp T.P.Hughes, A.H. Baird, (2003), Climate change, human impacts and resiliance of coral reefs (vol. 301, pp )