Tree diversity assessment of the beach forest trail of Puerto Princesa Subterranean River National Park.

Abstract

The tree species diversity and edaphic factors of the beach forest trail of Puerto Princesa Subterranean River National Park (PPSRNP) were assessed in this study. A modification of the Point Center Quadrat Method (PCQM) was employed for the sampling of the tree species. The importance value of each family and tree species was computed and the species richness and diversity of the site were measured using Shannon-Weiner, Simpson’s and Margalef’s indices. Soil samples were also gathered to give an ecological description of the soil along the trail. The trail had two zones, the true beach forest and the ecotone, designated based on the combined results of soil analysis and floral composition of the areas. The most important family is Calophyllaceae and the most important species is Calophyllum inophyllum. This species can survive in the beach forest despite the high leaching of the nutrients in the soil. The high species richness and diversity (Shannon-Weiner Index of Diversity - 1.812, Simpson’s Diversit y Index - 0.014, and Margalef’s Index 36.112) at the site were attributed to the relatively low level of disturbance at the site as well the edge effect since the beach forest meets with the mangrove and lowland forests.