Orchid Distribution along the Elevation Gradient in Panchase Forest Conservation Area of Gandaki Province, Nepal

Abstract

The vegetation composition and elevation play a key role in the distribution of plants. Among the flowering plants, orchids are widely distributed beautiful flowers having ornamental and medicinal values. The Panchase Forest Conservation Area is one of the hot spots for the orchids, a threatened group of the flowering plants. The preceding studies on orchids seem usually focused on documentation of the orchid species and their medicinal values showing no works on orchid species distribution along the elevation gradient and aspects. Therefore, this research was concentrated on assessing orchid distribution along the elevation in the forest of the Middle-mountain. The study was conducted in former Chapakot and Bhadaure-Tamagi Village Development Committees that lie in Pokhara Metropolitan City-23 and Annapurna Rural Municipality-4, Kaski District. Chapakot represents south-west (SW) aspect and Bhadaure-Tamagi represents north-west (NW) aspect. For this study, the belt-transect method with 20 m x 20 m quadrat size at an interval of 100 m elevation was used for assessing the orchid richness along elevation and aspects. Altogether, 61 orchid species, with Eria, Dendrobium, Cymbidium and Bulbophyllum as the most common genera, were found. Among the orchid species, Dendrobium gibsonii was not reported in earlier studies from Panchase area. The orchid richness varied along the elevation and aspect. The SW aspect showed fluctuation in orchid richness, whereas the NW aspect showed humped shaped pattern. Further detailed studies on factors causing distribution of orchids and their relationship with host species need to be conducted for the conservation of orchids in the Panchase Forest Conservation Area.