Forest vegetation of a protected area (Binsar Wildlife Sanctuary) in Kumaun region (west Himalaya) was analysed for structure, composition and representativeness across three different altitudinal belts, lower (1...Forest vegetation of a protected area (Binsar Wildlife Sanctuary) in Kumaun region (west Himalaya) was analysed for structure, composition and representativeness across three different altitudinal belts, lower (1,6oo-1,8oo m a.s.1.), middle (1,900-2,100 m a.s.1.) and upper (2,200-2,400 m a.s.1.) during 2oo9-2011 using standard phytosociological methods. Four aspects (east, west, north and south) in each altitudinal belt were chosen for sampling to depict maximum representation of vegetation in the sanctuary. Population structure and regeneration behaviour was analysed seasonally for two years to show the establishment and growth of tree species. A total of 147 plant species were recorded from the entire region of which 27 tree species were selected for detailed study. Highest number was recorded at upper (18 species), and lowest at lower altitudinal belt (15 species). The relative proportion of species richness showed higher contribution of tree layer at each altitudinal belt. The population structure, based on the number of individuals, revealed a greater proportion of seedling layer at each altitudinal belt. The relative proportion of seedlings increases significantly along altitudinal belts (p〈0.05) while opposite trends were observed in sapling and tree layers. The density of sapling and seedling species varied non-significantly across seasons (p〉0.05). The density values decreased in summer and increased during rainy season. As far as the regeneration status is concerned, middle and upper altitudinal belts showed maximum number of species with fair regeneration as compared to lower altitudinal belt. Overall density diameter distribution of tree species showed highest species density and richness in the smallest girth class and decreased in the succeeding girth classes. This study suggests that patterns of regeneration behaviour would determine future structural and compositional changes in the forest communities. It is suggested that the compositional changes vis-a-vis role of 'New' and 'Not regenerating' species need priority attention while initiating conservation activities in the sanctuary. This study calls for exploring other less explored Wildlife Sanctuaries in the Himalaya and across the world, to achieve overall biodiversity status in these protected areas and thus to justify their role in conserving biodiversity in the region.展开更多
基金Council of Scientific and Industrial Research (CSIR) (File No: 09/560(0015)/2011-EMR-I)India and OCB programme of UNU, Tokyo, Japan for financial support to Balwant Rawat and Vikram Negi
文摘Forest vegetation of a protected area (Binsar Wildlife Sanctuary) in Kumaun region (west Himalaya) was analysed for structure, composition and representativeness across three different altitudinal belts, lower (1,6oo-1,8oo m a.s.1.), middle (1,900-2,100 m a.s.1.) and upper (2,200-2,400 m a.s.1.) during 2oo9-2011 using standard phytosociological methods. Four aspects (east, west, north and south) in each altitudinal belt were chosen for sampling to depict maximum representation of vegetation in the sanctuary. Population structure and regeneration behaviour was analysed seasonally for two years to show the establishment and growth of tree species. A total of 147 plant species were recorded from the entire region of which 27 tree species were selected for detailed study. Highest number was recorded at upper (18 species), and lowest at lower altitudinal belt (15 species). The relative proportion of species richness showed higher contribution of tree layer at each altitudinal belt. The population structure, based on the number of individuals, revealed a greater proportion of seedling layer at each altitudinal belt. The relative proportion of seedlings increases significantly along altitudinal belts (p〈0.05) while opposite trends were observed in sapling and tree layers. The density of sapling and seedling species varied non-significantly across seasons (p〉0.05). The density values decreased in summer and increased during rainy season. As far as the regeneration status is concerned, middle and upper altitudinal belts showed maximum number of species with fair regeneration as compared to lower altitudinal belt. Overall density diameter distribution of tree species showed highest species density and richness in the smallest girth class and decreased in the succeeding girth classes. This study suggests that patterns of regeneration behaviour would determine future structural and compositional changes in the forest communities. It is suggested that the compositional changes vis-a-vis role of 'New' and 'Not regenerating' species need priority attention while initiating conservation activities in the sanctuary. This study calls for exploring other less explored Wildlife Sanctuaries in the Himalaya and across the world, to achieve overall biodiversity status in these protected areas and thus to justify their role in conserving biodiversity in the region.