6. Coral is one of the ecosystems in the sea. Society of the coral reef is composed of several kinds of organisms live together. Organisms that cause significant coral reefs are the coral reefs which are invertebrates. On the basis of calcium from seawater in the Bay area, especially the small fragrant Thai Nan in the coral reef will not be accumulated until the coral reefs, but only bundled in the right place. Like the coral islands and Ko Si Chang Strip development, etc. Coral reefs are found in the small fragrant lanes scattered around the Bay, both in the Thai coastal areas and Islands. When the separate types of coral, about 55 percent. In the province of Ranong, Phang-Nga, Phuket, Krabi, Trang, Satun best 45 percent of all coral species found in Thai Gulf Coast islands scattered along. Chon buri, Rayong, chanthaburi, Trat province prachuap khiri Khan, Chumphon and Surat Thani.