COMPOSITION, DIVERSITY, AND VEGETATIVE STRUCTURE OF MANGROVES IN SAMAR, PHILIPPINES

Samar is one of the Philippines’ provinces with extensive mangrove cover, which could be a potential biological hotspot. However, information on its status is scarce and this study seeks to gather information on developing conservation strategies applicable to Samar. Hence, this study investigates the composition and diversity of mangrove species in the province. Accordingly, 69 10 m × 10 m plots were assessed using the Transect Line Plot (TLP) method to obtain the data on the forest structure and diversity indices were used for the mangrove biodiversity. In particular, 20 mangrove species were identified. Avicennia marina, Rhizophora apiculata, and Sonneratia alba were the most widespread and ecologically dominant species based on their high Importance Value Index (IVI) and basal area. Meanwhile, the Shannon Diversity Index only ranged from 0.87 to 1.56, indicating a low level of mangrove diversity. Furthermore, the results revealed that although the mangroves of Samar fall short on the diversity scale, the dominance of the few species offers information for identifying suitable species that can be utilised as planting materials. Nevertheless, the environmental factors influencing species dominance should be investigated and long-term monitoring should be explored to assess the success of mangrove restoration initiatives in Samar.