VEGETATION ANALYSIS AND COMMUNITY STRUCTURE OF MANGROVES IN ALABEL AND MAASIM SARANGANI PROVINCE, PHILIPPINES

The study was conducted in order to establish and describe the mangrove community and vegetation of the mangrove forest in Alabel and Maasim, Sarangani province. It was evident that the studies for mangrove vegetation were really few in Sarangani bay. Thus, this study will serve as baseline information. Sampling plots (10m x 10m) were established into sea ward, middle ward and landward. Individual plants found within the plot were identified and counted. Mangrove vegetation analyses were determined using relative density, relative frequency, relative dominance and importance value. Community structure was analysed using multivariate analysis performing non-metric multidimensional scaling (nMDS), cluster analysis and one way ANOSIM. Mangrove communities in Alabel and Maasim, Sarangani province have identified 12species; A. marina, L. racemosa, P. acidula, A. floridum, X. granatum, B. gymnorrhiza, B. cylindrical, C. decandra, C. tagal, R. apiculata, R. mucronat andS. alba out of 39 true mangroves reported in the Philippines. Vegetation analysis in Alabel showed that species with the highest importance value wasA. marina (84.72%) and S. alba (158.72%) in Maasim sampling site. Cluster analysis showed moderate similarity among plots observed from the same site than plots from different sites. All the 21 sampling plots in Alabel and 20 in Maasimwere clustered based on similarities and formed into 3 groups with 40% similarity. Data ordination in nMDS revealed that characteristic similarity of same sites was analogous with ANOSIM of (R=0.317, P=0.001) but very minimal similar characteristics were observed in Alabel sampling plots to Maasim sampling plots. Results shows A. marina and S. alba as species with highest importance value with mangrove structure showing no distinct characteristics on the two sites.