Spatial Distribution of Biodiversity Risk Index in Truong Sa Islands Marine Zone, Vietnam

The biodiversity of marine ecosystems is the foundation for the sustainable development of several marine economic sectors based on natural resources such as tourism, fisheries, and marine medicine in marine countries, including Vietnam. Truong Sa Islands (TSIs) is an offshore archipelago located in the southeast of Vietnam, a significant marine zone because of its rich biological resources and diversity of marine life. The study aimed to clarify the spatial distribution of biodiversity in the area using the International Union for Conservation of Nature (IUCN) Red List, from which a total of 839 species of six groups, including seagrasses, cone snails, reptiles, marine fish, lobsters, and mammals, were extracted. The biodiversity risk index (BRI) map revealed priority areas for conservation. It was calculated by averaging the conservation status of the species on a GIS-based cell-by-cell basis. The results showed the most species-rich area accounts for more than 45% of the total area and ranges from a depth of 400–1050 m, and the most threatened species are located in the coral reef zone. Analytical and comparative results between the six study plots illustrated that Thuyen Chai’s area (Barque Canada Reef) has the highest BRI, followed by Toc Tan (Alison Reef) and Nam Yet (Namyit). Based on the BRI, figuring out the order of the sea is an important step in making plans and strategies for marine economic development and protecting marine biodiversity.