Composition and structure of trees and saplings in the broadleaved forests of Singalila range, Darjeeling

The present study was carried out in three forest stands – SI, S2 and S3, located at 1900 m, 2600 m and 2800 m elevations, in Darjeeling. The stands harboured the typical broadleaved species of the East Himalayan Moist Temperate forests. Vegetation analysis for trees and saplings was carried out by quadrat method and the density (D), basal area (BA) and diversity were evaluated. A total of 24 tree species were recorded, of which S I had 13 species (D-740 ha-1, BA-48.23 m3 ha-1) and was dominated by Castanopsis purpurella. At S2, there were 12 species (D-840 ha-1, BA – 63.04 m2 ha-1) with dominance of Lithocarpus pachyphylla and Rhododendron spp. At S3, there were 9 species (D-620 ha-1, BA-30.33 m2 ha-1) with Cryptomeria japonica and Rhododendron spp. Dominating. The sapling layer was poorer in comparison with a total of 16 species. There were only 8, 9 and 5 species at S1, S2 and S3, respectively and the density ranged between 480 ha-1 and 900 ha-1. Both the trees and saplings showed low similarity values between the stands and a predominantly random distribution pattern. The tree and sapling diversity ranged between 2.917-3.385 and 2.305-3.026, respectively.