Tree Regeneration, Diversity and Carbon Stock in Two Community Managed Forests of Tanahun District, Nepal

Abstract

Studied community forests lie in low elevation (500m to 620 m) of western Hill in Tanahun district of Nepal. Taldanda Community forest (TF) of Dulegauda VDC is regenerating forest and being managed by communities since twenty years, while Fulbari Community forest (FF) of Chang VDC is older and growing. Carbon stock of tree species of both forest were determined by allometric regression model and species diversity by Simpsons and Shannon –weaver index. Fulbari CF found to have lower value of tree carbon stock (71.11 per ha) as well as tree diversity (H1=0.9978) than the carbon stock (109.82 ton per ha) and diversity (H1=1.1835) of Taldanda CF. Statistical analysis through T- test did not show significant difference for mean values of their carbon stock and density but significant different in mean value of diversity, DBH and basal area of two forest types. ANOVA- Test showed significant difference between the mean values of carbon stock and diversity among the strata of Fulbari CF (log carbon, P=0.00 and log H1, p=0.001) while test did not show significant difference in mean values carbon stock (p=0.001) but significant difference in diversity (p=0.0045) among the strata of Taldanda CF. There was no significant difference in other stand attributes like density, basal area and DBH among the strata of both forest types. Two way ANOVA showed Proximity of strata from road or settlement had significant effect on carbon stock among the strata in Fulbari CF (p=0.003) but there was no significant effect of recent disturbance (p=0.882 in Fulbari CF and p=0.181 in Taldanda CF) and combined effect of both proximity and disturbance (p=0.226 in Taldanda CF and p=0.138 in Fulbari CF) on tree carbon stock in both forest types. Shorea robusta was found the single dominant species in Fulbari CF (higher value of Simpsons index and basal area) and contribute about 64% of carbon stock while in Taldanda CF Shorea contribute 44% of carbon stock . Shorea along with Schima also have comparable dominancy in Taldanda CF.There was Significant positive correlation and relationship of carbon stock with diversity (R 14

2 =0.371, p=0.0023) in Fulbari CF, while density showed significant positive relationship with carbon stock and tree diversity of Taldanda CF.