by Yuri LATYPOV, Dr. Sc. (Biol.), manager of the Laboratory of Benthos Ecology of the RAS Far Eastern Branch Institute of Marine Biology
Surveys of ecosystems of tropical seas have been carried out in our institute since the day of its foundation at the Pacific Ocean shore in Vladivostok. We first visited cays more than 30 years ago and now have a complete idea of a great biological diversity of this unique community, its structure, problems of existence under the conditions of increasing anthropogenic pressure; besides, we realize how to preserve and keep it for the future. Our knowledge is proved by results of experiments carried out on the Mieu and Mun islands near Vietnam coast.
According to the last data, there are 382 species of reef-building corals of 80 genera living near Vietnam coast. A third of them (133 of 26 genera) was described by scientists only at the end of the 20th-beginning of the 21st century, 12 species of 6 genera having been unknown to the scientists before that time. Such a diversity (which is possible for the reason of a high content of biogenic elements in comparatively shallow local waters) does not cause deposition of thick sediments on cays. But these cays, analogous to formations of the Indian Pacific region, which are well formed from the point of view of structure and morphology, are characterized by a bionomic zoning: heterotrophic organisms dominate the internal slopes, and autotrophic organisms, the outer slopes.
Cays of Indonesia, the Philippines, and the Great Barrier Reef of Australia are considered the faunistical center of origin of tropical corals, which is not by accident: about 360 - 410 species of scleractinia belonging to 70 genera live in this region of the south-western part of the Pacific Ocean (Dr. Charlie Veron from the Australian Institute of Marine Science, 1995; author of the present article, 2005). Maximal variety of these organisms is observed in a so-called "fertile" t ... Read more