Seed storage and seedling performance of tangal [Ceriops tagal (Perr.) C.R. Rob] at the different mangrove zones in southern Leyte [Philippines]

Traditional and cultural practices of coastal dwellers really affected the natural process on regeneration of tangal because they already cut at sapling stage. Seldom can they reach the reproductive stage due to premature utilization. On the other hand, the variability of tangal seeds can be prolonged through appropriate storage technique using the ordinary jute sack. The successful establishment of tangal plantation also depends on the site conditions. Favorable growth was evident on the landward zone due to less disturbance from tidal inundation, soil fertility, and fishing activities. Results on studies on seed storage of tangal propagules under normal room temperature indicated the highest percentage germination from jute sack (98%) followed by cellophane (96%), cloth (95%) and nylon net (94%). The control treatment, sown immediately after collection had a 100% germination. However, ANOVA showed no significant differences among the treatments. Belt survey was the method adopted during the timber inventory. Total effective area inventoried was 15 hectares with 9 transect lines.Barangay [village]Lib-og is composed of 17 mangrove species and associates under 9 families. In terms of importance value, the following species are from highest to lowest ranks: Rhizophora apiculata (129.77), R. stylosa (48.48), Sonneratia alba (43.27), Avicennia marina (39.63), A. officinalis (11.57), Bruguiera gymnorrhiza (5.55), Lumnitzera littorea (0.62) and Ceriops tangal (0.53). Regeneration was excellent in R. apiculata with an average number of seedlings per hectare of 2,698, followed by R. stylosa at 698 seedlings. Ceriops tangal had zero regeneration. Statistical analysis showed that survival height and diameter of tangal seedlings were not significantly affected by the different zones and exposures on the 13th month of observation. However, the number and length of leaves were highly significant in exposures and zones. Similarly, the width of leaves and moisture content of the plant were significant at the different zones. Root-shoot ratio was significantly affected by the type of exposures and highly significant with the interaction of exposures and zones. Some seedlings, mostly in the landward zones and under shaded plots, were infested with larvae believed to be of Geometridae, Looper worms that defoliate the seedlings. Spot holes on the leaves were likewise infested with chrysomelid beetles. The ideal plantation site for tangal is in the landward zone preferably from the middleward toward the innerland part of mudflats. Tangal grows well in open site. When seedlings are used, the height should be at least 45 cm tall because they are sturdy and tall enough to resist tidal inundation. New plantation should also need daily visits to free the seedlings from debris during high tide