ECOLOGICAL STUDY AND DISTRIBUTION OF PTERIDOPHYTE ALONG THE ELEVATIONAL GRADIENT OF PHULCHOWKI HILL, CENTRAL NEPAL

Abstract

The present study aims to find the relationship between pteridophyte richness along the elevational gradients of Phulchowki Hill, Central Nepal. The study was carried out in three elevational zones namely lower (1500-1900 masl), middle (1900-2300 masl) and upper elevation (2300- 2700 masl), starting from 1550 masl and ending to 2698 masl of Phulchowki Hill at an interval of 100 m. Random number of quadrats having 5m × 5m sizes were laid at each elevation band. SPSS- Software and Microsoft Excel were used to perform the statistical analysis. All together 46 (39 terrestrials and 7 epiphytic) pteridophyte species belonging to 28 genera and 14 families have been documented. Among the 14 families Polypodiaceae was found to be the largest family having highest number of genera followed by Pteridiaceae. However, Pteridiaceae was found as largest family on the basis of highest number of species followed by Dryopteridaceae and Polypodiaceae. Plant community properties such as species richness, diversity, and composition vary along environmental gradients. Species richness of tree species showed asymmetric hump shaped pattern of distribution with elevational gradients. The pteridophyte species richness significantly differs along the elevational gradients within different sites. Pteridophyte species like Selaginella chrysocaulis, Dryopteris carolohopei were dominant in lower elevational zone; Polystichum squarrosum, Drynaria moliis were dominant in middle and Polypodiodes hendersonii, Drynaria moliis were observed dominant in upper elevational sites. The Spearman's correlation analysis table shows elevational gradient strongly affects the pteridophytes richnes