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3 a) Describe the conditions which provide the best environment for the growth of coral and explain how coral may be threatened by changes to those conditions.
A coral reef provides one of the most important natural habitats in the world, sheltering enormous amounts of biodiversity with its solid calcium carbonate skeleton. More than 25 percent of all fish biodiversity on the planet Earth is associated with the coral reef ecosystem.
Coral reefs require fairly specific environmental conditions in order to thrive. Coral reefs and the zooxanthellae algae living within the cell walls of coral polyps must have adequate sunlight and warm salt water - water that gets no ...view middle of the document...
As temperatures rise, mass bleaching and infectious disease outbreaks are likely to become more frequent. Additionally, carbon dioxide (CO2) absorbed into the ocean from the atmosphere makes the ocean water more acidic, and dissolves the skeletons of coral, which are made of calcium carbonate.
Fishing impacts in coral reef areas, when ecologically unsustainable, can lead to the depletion of key functional groups of reef species in many locations, with cascading impacts on coral reef habitats and their associated species and ecosystems.
Impacts from land-based sources of pollution (e.g. agriculture, deforestation, storm water, impervious surfaces, coastal development, road construction, and oil and chemical spills) on coral reef ecosystems include increased sedimentation, nutrient enrichment, toxins, and pathogen introduction. These pollutants and related effects can cause disease and mortality in sensitive species, disrupt critical ecological functions, and impede growth, reproduction, and larval settlement.
Other threats to corals that have been deemed important and relevant across all U.S. jurisdictions include: coral disease; tropical storms; tourism and recreation; vessel damage; marine debris and pollution; and aquatic invasive species.
Warm water emissions from factories, where water is used as coolant, is released back into the oceans, which raises the temperature of water.
Conservationists have suggested coral reefs can be protected if we take measures to limit greenhouse gas emissions and establish Marine Protected Areas (MPAs) to shield existing reefs from destructive human activities. In the long term, failure to address carbon emissions and the resultant impacts of rising temperatures and ocean acidification could make many other management efforts futile.
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4 a) Explain how any three of the threats can affect the conditions necessary for the growth of coral and the survival of coral reefs.
More than 20 percent of tropical reefs worldwide have been destroyed and are unlikely to recover. Coral reefs are threatened by a multitude of reasons, the main ones being climate change, pollution, and unsustainable fishing.
Climate change impacts have been identified as one of the greatest global threats to coral reef ecosystems. As temperatures rise, mass bleaching and infectious disease outbreaks are likely to become more frequent. Even a one degree rise in temperature can damage coral, causing it to expel its symbiotic algae in a process known as coral bleaching. It's called bleaching because the algae is what gives coral its color. Without it, the coral takes on a stark white appearance. If the stress is prolonged, the algae will not return, and the coral will die. Additionally, carbon dioxide (CO2) absorbed into the ocean from the atmosphere makes the ocean water more acidic, and dissolves the skeletons of coral, which are made of calcium carbonate.
Fishing can be problematic for several...