ABSTRACT
Oceans cover 70 percent of the Earth surface. Coastal and shallow water areas contain the most productive and diverse ecosystem, including coral reefs, mangroves and sea grass beds. Coral reefs, as referred to the tropical rainforest of the ocean, is a marine system whose valued about 30 million USD per year: Coral protects shares and islands from the strong waves and surges. Along with sea grass beds and mangroves, coral reefs acts as the biggest carbon sink from atmosphere in the earth. The tropical coral reefs worldwide cover an area of 284. 000 km2 can absorb carbon as much as 4 milion tons carbondioxide every year: It is five times higher than tropical rain forests can absorb. It is why people called it as blue carbon. On the other hand, some people say that coral reef is also acts as the carbon source.