Coral Reefs
Coral reefs, like coastal wetlands, perform important ecological functions, such as harbouring marine fish and nursing their progeny. They are highly bio-diverse, with some reefs containing more major plant and animal groups than rain-forests. They also serve as protective barriers to coastlines that reduce the effects of storm waves and surges. However, more than half of the total area of living coral reefs is thought to be threatened by human activities ranging from water pollution to coral mining. How will coral reefs be affected by global change? It appears that simple sea-level rise will not be a factor because healthy coral reefs are able to grow upward at a rate equal to or greater than projected sea-level rise. However, the increase in sea-surface temperature that will accompany global warming is of major concern. Many coral reefs appear to be at or near their upper temperature limits. When stressed, for example by a rise in temperature, many corals respond by ‘bleaching’. In this process, they expel the algae that live symbiotically inside their structures, leaving the coral without colour. The bleaching may be temporary if the stress subsides, but if permanent, the corals die. Major episodes of coral bleaching have been associated with the strong El Niño’s where water temperatures were increased by at 1C. During the very strong El Nino of 1997-1998, the Indian Ocean experienced a major coral bleaching event that was especially prominent on Australia’s Great Barrier Reef.
|
Login
Favorites
From the Vault
Quick Vote
| Please Rate Our Website |
| Poor | |
| Fair | |
| Average | |
| Good | |
| Excellent |