Study Site
The assessment of mangrove forest ecosystem was carried out in Butig Island, Salcedo, Eastern Samar from February – April 2014. Butig Is. is located at 11° _________N; 125° ______ E. Geographical coordinates of the study site were determined using the GARMIN GPS unit, and was plotted in Manifold. The map of the study site is shown in Figure 1.
Figure 1. Map of Butig Island showing the seven plots
Field Sampling
Physico-Chemical Parameters The physico-chemical parameters, including temperature, pH, and salinity of each plot were determined in situ. Water temperature was measured using a thermometer. The pH was determined using a pH meter, and salinity was measured using the handheld ATAGO refractometer.
Mangrove Damage and Recovery Assessment
The methods employed in this study were based from Roth (1992) and Taylor et al. (2013) with some modifications. In the island of Butig, seven 100 m2 plots were established. The plots established were based on the vegetation types present.
I. Species Composition
All mangroves rooted within the plots were recorded and identified in situ. The Handbook of Mangroves in the Philippines – Panay by Primavera et al. (2004) and Field Guide to Philippine Mangroves also by Primavera (2009) were used as principal resources in identifying the species. Mangroves were categorized into three: trees, saplings, and seedlings. For individuals having greater than or equal to 2.5 cm DBH (girth at breast height, or 1.3 m above ground level), they were categorized as trees. GBH (cm) of each tree was measured using a measuring tape. For forking or branching stems, measurement was done separately. For the seedlings and saplings, they were only identified and counted. Other observations, such as debris and substrate type, were also noted.
II. Recovery
Typhoon impacts on the areas were recorded. Trees within the plots were judged as dead or alive, and assigned to one of three structural