THESIS ABSTRACT

Abstract

Silviculture-Based Sustainable Forest Management (SBSFM) has been promoted in Nepal as a key strategy for enhancing forest productivity, regeneration and biodiversity in community-managed forests. Field-based evidence on how specific silvicultural interventions influence regeneration dynamics and species diversity across successive post-harvest stages nonetheless remains limited. This study therefore assessed regeneration status, species composition and diversity patterns under SBSFM practices in four community forests of the Saljhandi area, Rupandehi district, Nepal. Forest stands were categorised into three treatment groups – First, Third and Fifth – according to the number of years elapsed since silvicultural intervention. Sixty concentric circular sample plots (CCSPs) were established using a systematic random sampling design, with 20 plots allocated to each treatment group. Height, diameter and species identity were recorded for seedlings (height < 1.3 m) and saplings (height ≥ 1.3 m and DBH < 10 cm) as primary data. Regeneration density increased progressively across treatments: seedling density rose from 37,389 individuals ha−1 in the First treatment to 48,964 individuals ha−1 in the Fifth, while sapling density rose from 14,036 to 22,667 individuals ha−1. One-way ANOVA confirmed these increases were statistically significant (p < 0.001), and were accompanied by a significant decline in sapling height and DBH across the same treatment sequence, indicating a density-dependent growth trade-off. Diversity analyses showed lower heterogeneity and higher dominance at the seedling stage, whereas saplings exhibited higher species heterogeneity, richness and more stable evenness, particularly under later treatments. Overall, the study demonstrates that SBSFM practices effectively enhance natural regeneration and promote species diversity over time in community-managed Sal forests. The findings provide an evidence base for adaptive silvicultural planning that balances regeneration success, growth performance and biodiversity conservation under sustainable forest management in Nepal.

Keywords

Silviculture based sustainable forest management, silviculture, species diversity and regeneration.