Stocking Density and DBH Distribution of Community Forests in Nepal

Abstract

There is a growing concern for sustainable forest management globally, and individual countries have been developing national policies and plans for forest management. This is the case in Nepal, but a large area of national forests is still under protection due to lack of people-centric management guidelines. In this study, diameter (DBH) and height were measured for trees, and frequency was recorded for regenerations (sapling and seedling), in concentric circular plots of 8.92 m, 5.64 m and 1 m radius respectively, in 89 plots from two community forests in the Mid-hills of Western Nepal to analyze whether the forests could be used sustainably. Regression analysis and the Mann–Kendall and Sen’s slope coefficient tests were performed to determine the composition and structure of forests in relationship with elevation which largely determines forests' type. It was found that seedling density decreases with increasing elevation, but sapling and tree density do not follow any significant pattern for elevation. The DBH size found to be inversely related to stand density for the two dominant tree species (Shorea robusta and Schima wallichii). In contrast, DBH did not vary significantly with elevation for Pinus roxburghii and Castanopsis indica. The DBH distribution of all trees (26 species) was found to decline consistently with stand age, indicating that the forests are in good condition to manage sustainably by a simple, people-centric and cost-effective regime of thinning and size-based harvesting. Results suggest that forest managers, forest users and policy-makers need to develop and implement user-friendly forest management directives.