Encrusting protected reef Hon Nai in Cam Ranh Bay in the South China Sea

Abstract

A protected non-structural reef in Сam Ranh Bay in southern Vietnam was surveyed. A high diversity was found among scleractinian and accompanying mass species of macrobenthos. Thirtyfour species were identified only among genera Acropora; it made 80% of the total composition of these Scleractinian on reefs of Vietnam and a quarter of the total abundance of these corals on reefs in the Indo-Pacific. A new species, Favites сamranensis sp. nov, earlier unknown for science, has been found. The vertical bionomic zonality corresponding to zonal distribution of environmental factors on the reef under study is similar to that on reefs of the Siam Bay, different regions of the Pacific and the Caribbean Basin. Expansion of prosperous state of the reef and minimization of anthropogenic influence on some reefs of Vietnam had a positive effect on their state. It is supposed, that the reef at Hon Nai Island is obliged by the prosperity to security measures and minimization of the anthropogenous influence, provided with the decision of government SRV and company "Sanest".

The spatial-temporal variability and stability of Vietnamese reef communities

“…Exam ples include the reefs of the Hon Tre and Den islands in Khanh Hoa Province, which are under the protec tion of the state, as well as reefs of Bach Long Vi Island and the Spratly Archipelago [11,35,46,48,54], which are located distant from populated areas. This is also corroborated by the results of recent studies (2010, 2013) of the coral reef of the Con Dao Islands, which is an ecosystem that is not subjected to pronounced human impacts and has been optimally preserved for the past quarter century [13,[33][34][35]. Some reefs of these islands have been declared a national park and are under the protection of the state.…”

“…As a result, the identified species richness of the reef building sclerac tinians of Vietnam increased by more than 4% and reached 376 species. Since the composition and distri bution of the reef biota were described in detail previ ously [12,13,33,34], we will focus on the changes that have occurred in some reefs in the past 10-12 years.…”

“…These reefs are characterized by bionomic zoning, sig nificant species richness, and a high degree of sub strate coverage with corals [11,12,33]. It is believed that to maintain high species diversity on coral reefs repeated changes in species composition are needed.…”

Features of Formation of Structureless Reefs near the Mainland and Island Coast of Vietnam

“…Such reefs spread along the entire coast of Vietnam and its islands, and are formed near rock and rocky coasts. Different types of reefs, as well as the composition and structure that form their communities, have been repeatedly described in detail in various articles and monographs [3] [4]- [6] [7] [8]. Information on unstructured reefs is rather limited [9]- [12].…”