Внедрение искусственных конструкций Reef Ball в морских акваториях Южно-Центрального Вьетнама для восстановления коралловых рифов: первые достижения

Abstract

Among different methods of coral reef rehabilitation worldwide, the Reef Ball^TM technology based on artificial concrete modules mimicking natural reef structures is well-known and is used for more than three decades in over 56 countries. These modules serve as habitat promoting an increase of fish diversity as well as appropriate hard substrate for natural coral recruitment and artificial coral transplantation efforts. The project on implementation of Reef Ball (RB) method in south-central Vietnam was launched in 2023 using two sets of RB modules in two different coastal marine areas (protected (MPA) and recreational (RA)). The present study aimed to estimate the efficiency of these structures in promoting coral recruitment and enhancing fish diversity and abundance. The 1-year exposition of RB modules revealed similar coral recruitment patterns between RA and MPA with the dominance of Porites and Pocillopora. The density of coral recruits reached 9.5 ± 2.2 recruits/module and 8 ± 2.1 recruits/module in MPA and RA respectively. Fish diversity and abundance in MPA reached 18 species and abundance 131 ± 6 fish·100 m^-2, whereas RA exhibited respectively 10 species and abundance 110 ± 7 fish·100 m^-2. The longer 3-year exposition of RB modules in MPA revealed 4-fold increase in density of recruits to 42.5 ± 6 recruits/module and overwhelming dominance of Porites in recruitment pool. Fish abundance in this period exhibited 2-fold increase whereas their diversity increased to 33 species. This study showed that RB modules can be effectively used for reef ecosystem rehabilitation in coastal areas with different exploitation status; however protection from anthropogenic impacts may significantly enhance the outcome of this technology in marine environments.

Keywords: Reef Ball, Vietnam, coral recruitment, fish diversity, reef restoration