CORAL REEFS: A BRIEF REVIEW

Abstract

Coral reefs are often referred to as the ocean's rainforests and serve as a refuge with high gross primary productivity. They provide structural heterogeneity to a wide variety of creatures and provide numerous other ecological products and services. Coral reefs that have developed over the last half-million years are being jeopardised by coral loss and the related modification of reef habitats, which are risking the structure and function of coral reef ecosystems. They are valuable social, economicand environmental assets, but the diversity, frequency, and magnitude of human influences on them are increasing to the point that they are threatened globally. The resilience of the reefs is eroding to the point where it can no longer recover from recurring disruptions. Given these dangers and the value of coral reefs to humans and marine biodiversity, this papergives an overview of the types of corals, their organisation, formation, theories, zones of the reefs, biodiversityof coral reef ecosystems and their associated threats.