Indian Journal of Ecology

Several studies have reported on the influence of forest canopy gaps on understory plant growth and species richness. In this study, soil properties and the richness of understory vascular plants under forest canopy gaps of varying sizes in a permanent Long-Term Ecological Research (LTER) plot in Mt. Musuan were determined. Based on the results, the light and photosynthetically active radiation varied among canopy gaps. There was an observed variation in the mean pH, percent organic matter content, extractable P and exchangeable K among forest canopy gap classes but the variations were not statistically significant. Large gaps had higher species richness of trees, shrubs and vines. Mean species abundance was also higher in large gaps (81) in comparison with small (60) and medium gaps (76). Although there are many species of trees present, there are only very few numbers of individuals. Donax canniformis (G.frost) K.Schum., Orania palindan (Blanco) Merr. and Calamus sp. were the most abundant species. The abundance of D. canniformis increased with canopy gap size which may indicate that it can easily spread in open sites. This could be indicative of the potential harm that the species can pose to tree regenerates if its spread is not controlled.