Species Diversity and Composition of Bryophytic Vegetation in Garhwal Himalaya with Special Reference to Kedarnath Wildlife Sanctuary (KWLS), Uttarakhand, India

摘要

Species diversity, attributes and community composition of moss-dominated vegetation was assessed in Kedarnath Wildlife Sanctuary in Garhwal Himalaya, India. Eight sites (viz., Chopta, Devharital, Kanchula-khark, Pothivasha, Tungnath, Gaurikund, Sershi and Triyuginarayan) situated on an elevational gradient from 1760 m to 3662 m asl were selected for the study. The composition of moss communities was quantitatively analyzed by randomly sampled quadrat method. Considering the species diversity in all types of substrates (soil, boulders, tree bark) of the sites, maximum species richness (SR) was recorded in the site Kanchula-khark (30) with greater richness in the soil and the minimum in Tungnath (10). SR increased with increasing elevation up to middle elevations and then showed a sharp decline with further increase in elevation. SR was also negatively related with total annual rainfall. The Simpson's concentration of dominance (Cd) was maximum in Tungnath (0.10) and minimum in Kanchula-khark (0.03). The SR and Cd were inversely related with each other in the study area. The moss vegetation of Devharital and Tungnath showed logarithmic distribution curve, which infers that important ecological factors are being shared more or less between species at these sites. "Whereas all the other study sites showed random-niche boundary curves, which infers that species in these cases combine self-limitation of population density with self-limitation of niche space and each species is restricted to fraction of community space. Most of the study sites shared less than 30% of the total species between them, which meant significant differences in the diversity of mosses across the habitats. The analysis provides a basis for assigning a workable conservation value to such an important heritage site consisting of mixed conifer forests and alpine meadows.