Investigation of the Vegetation Coverage Dynamics and the Frequent Occurrence of Dominant Species on Coral Islands in the Truong Sa Islands, Vietnam

Coastline vegetation cover monitoring is critical for human survival because of plants are known as the most important dunes stabilizer. Evaluation of vegetation using Geographical Information Systems (GIS) and Remote Sensing (RS) was carried out in some areas of the Truong Sa Islands (Truong Sa island: A1; Nam Yet island: A2; Sinh Ton island: A3; Son Ca island: A4; Song Tu Tay island: A5). The study’s primary goal was to analyze salt-tolerant plants based on a data field survey conducted between 2020–2022 using an analysis of Sentinel-2 images taken between 2016 and 2021. Most of the islands show an increase in vegetation cover. Overall, plant species have mostly grown on dunes and sandy soil: (1) Herbaceous plants are dominated by Ipomoea pes-caprae (L.) R.Br., Chromolaena odorata (L.) R.M. King and H. Rob.; (2) Shrubland communities are dominated by Poaceae, Asteraceae, Goodeniaceae families; (3) Group of woody plants are dominated by Heliotropium arboreum (Blanco) Mabb . , Barringtonia asiatica (L.) Kurz., Calophyllum inophyllum L., Coccoloba uvifera (L.) L., Casuarina equisetifolia L., Terminalia catappa L., Catharanthus roseus (L.) G. Don, Scaevola taccada (Gaertn.) Roxb. Results have shown that the islands located in the northern latitudes have more diverse flora than the islands in the southern part. The size of these coral islands has expanded from 2016 to 2021, leading to the growth of vegetation coverage and biodiversity support for human and societal needs. This study provides important data to expand further studies to islands in different latitudes, actively supporting biodiversity management and protecting remote islands’ soil and sand resources.