Species Composition and Carbon Stock of Selected Secondary Growth Forest Patches in Ilog-Hilabangan Watershed Forest Reserve

Abstract

A tree species composition and carbon stock assessment was conducted in selected secondary growth forest patches at Ilog Hilabangan Watershed Forest Reserve in Barangay Buenavista, Himamaylan City, Negros Occidental. The study aimed to (1) identify and enumerate the various tree species, (2) characterize the community structure of tree species in terms of species composition, diversity, evenness and richness, and (3) estimate the carbon stock of the remaining forest patches. In each sampling site, three 100-m transects were laid out, from which three 20m x 20m plots were established. The data collected from each sampling plots include tree count, species identification, and diameter at breast height. A total of 66 species of trees, belonging to 47 genera and 28 families were identified. The dominant species found were Parashorea malaanonan (pi=0.14) in NIDCO, Ficus variegata (pi=0.20) in Cansirmon and Shorea contorta (pi=0.39) in Candi-is. Forest patches in Cansirmon had the highest species richness (Dmg=12.75), while NIDCO had the highest tree species diversity (H’=3.01) and evenness (D=0.12). The highest carbon stock was estimated from NIDCO forest patches, with an average of 194.56 tons/hectare. This can be attributed to the dominance of old and larger trees in the sampling site. The study concluded that the level of disturbance of the site influences its diversity and carbon stock.