Composition and Regeneration of Trees in the Community Forests of Lamjung District, Nepal

Abstract

The community forest program in Nepal is one of the successful conservation initiatives. Tree species in a forest ecosystem have a fundamental role in maintaining the vegetation structure, complexity, and heterogeneity. This study analyzes the composition and regeneration of tree species in five community forests (CFs) of the sub-tropical region, Lamjung district, Nepal for preparing baseline data for long-term research projects and helps the community to manage their CFs scientifically. Tree species data were generated by stratified random sampling using 35 quadrate plots (size: 20 m × 20 m). The density of adult trees in the forests ranged from 575 Ind ha–1 (Tilahar CF) to 1196 Ind/ha (Deurali Thadopakha CF). The sapling ranged from 2533 Ind ha–1 (Tilahar CF) to 4000 Ind ha–1 (Thuliban CF) and seedling from 19583 Ind ha–1 (Tilahar CF) to 37500 Ind ha–1 (Thuliban CF). Similarly, the adult tree basal area varied from 28.34 m2 ha–1 (Tilahar CF) to 49 m2 ha–1 (Deurali CF). The adult tree diversity index (Shannon-Weiner's H) also ranged from 1.08 (Thuliban CF) to 1.88 (Tilahar CF). The tree species such as Sapium insigne, Ficus benghalensis, Lagerstroemia parviflore, Albizia sp. and Pinus roxburghii were weak regeneration. In general, the forests have good regeneration status except for Tilahar Community Forest, but based on the DBH size class distribution diagram, there is no sustainable regeneration. Among the five community forests the DBH size of adults was significantly different, and the DBH of Deurali Thadopakha was the lowest. But only few species have good regeneration and most of the species have weak, poor to no regeneration. The dominancy of fewer species like Shorea robusta, Castanopsis indica, and Schima wallichii accordingly maintain the overall regeneration of tree of CFs, so further plantation needs to be done inside the CF by triage accordingly those species whose regeneration has poor.