The composition and structure of a protected coral reef in Cam Ranh Bay in the South China Sea

Abstract

112The Hon Nai Islands are a group of islands located 11 km to the east of the coastline between the cities of Cam Ranh and Nha Trang. The largest Noi Island is somewhat more than 0.8 km long from north to south (12°03′50′′ N, 109°19′85′′ E and 12°02′75′′ N, 109°19′70′′ E). The island is made of large blocked dacite and is surrounded by a sandy platform with depths of 6-15 m along the eastern side and 9-20 m at the western coast. The bedrocks of the island and their blocky debris stretch from southwest to northeast in 5-20 m wide bands. Coral settlements develop mostly on submarine bedrock exposures and, in smaller amounts, on a corallogenic substrate that is composed of blocks no more than 1 m in size. The island is the property of the Sanest Co., which abso lutely prohibits any access to its submarine resources. The coral ecosystem developed at the southwestern part of the island is characterized by surprisingly clear water and extremely high species diversity of reef building corals and associated organisms, thus differ ing significantly from the ecosystems of the adjacent mainland and insular reefs [8,12].The specificity of geomorphology and climatic conditions allows one to divide the reefs of the World Ocean, in particular, the reefs of Vietnam, into two types. The reefs of the first type, also called "structural reefs" [33], demonstrate pronounced zonation (com prising lagoons, reef flats, etc.) and strong corallogenic carbonate structure; they are common in the tropical zone of the World Ocean. In reefs of the second type, including the reef at Noi Island, the morphological zonation is weakly pronounced and carbonate depos its develop small scale coral populations that make almost no changes to the substrate profile; however, their bionomical zonation is comparable with that of the structural reefs. These are so called non structural or encrusting reefs that often occur among reefs of the monsoon type [21,33]. The species diversity of the reef at Noi Island, which is unusual for the present time, motivates the necessity for investigations of the species composition and distribution peculiarities of scleractinians and associated macrobenthos of this reef. MATERIALS AND METHODSThe composition and distribution of scleractinians and common macrobenthic species and community structure in each reef zone at Noi Island were studied using scuba gear (Fig. 1). The studies were performed following generally accepted hydrobiological tech niques, with transects and standard frames [25]. The density of branched, massive, encrusting, and funnel form scleractinian colonies and the degree of substrate coverage by corals were estimated along a 100 m long transect using a 1 m 2 frame divided into 100 equal parts. At the same time we also determined the density of common species of macrophytes and echinoderms, HYDROBIOLOGY Abstract-A nonstructural reef at Hon Nai Island in Cam Ranh Bay (southern Vietnam) was investigated. In comparison with most of the coastal continental and island coral reefs of this region, it is characte...

Trading Off Tourism for Fisheries

“…23 The remaining RZ increase could be located in different parts of Khanh Hoa waters, i.e. Van Phong and Cam Ranh Bays, where there exist similar characteristics regarding ecosystems, biodiversity, and tourism attractiveness as in NTB (Latypov & Selin, 2012;Son et al, 2008;Long et al, 2014;Phung et al, 2002;Quang, 2008).…”

A Short Review of the International Trade of Wild Tortoises and Freshwater Turtles Across the World and Throughout Two Decades

“…were recorded off Hon Nai island in Cam Ranh Bay (southern Viet Nam), E. cristata was not present (Latypov and Selin, 2012). Euphyllia spp.…”