Ferns and Lycophytes of Gori Valley, Western Himalaya, Uttarakhand: A Case Study

Abstract. This study was carried out in the Gori Valley catchment of Uttarakhand, Western Himalaya, to document more fully the distribution and ecology of ferns and lycophytes at a montane site divided into 7 elevation sampling zones from 1,800–4,000 m (subtemperate to alpine) across a distance of approximately 30 km. A total of 16 families, 33 genera, and 92 species were found. Species richness, total species density ha–1, diversity, and Pielou's species evenness per elevation zone (m) were calculated for each zone. The data were used to evaluate three hypotheses addressing changes in density and species distribution in relation to the biogeographic and climatic conditions across the seven elevation sampling zones. Total density of ferns and lycophytes tended to decrease from Zone 1 toward Zone 7; although Zones 1-3 (sub-temperate) had clearly higher mean densities than those in Zones 5-7 (alpine). The highest density was found in Zone 1 (Lilam 1,800 m) and lowest density was found in Zone 6 (Burfu 3,450 m). After finding a significant difference among all mean densities for each elevation zone (p < 0.001), using a non-parametric Welch's ANOVA, a Games-Howell test for pairwise comparisons of the means showed that each of the mean densities for species in Zones 1 to 3 was significantly different from each of the species densities in Zones 5 to 7 (p < 0.05). The mean densities for Zone 4 were not significantly different from any of the other zonal mean densities (i.e., 1–3 and 5–7), suggesting that Zone 4 is a transitional zone between two end member Zones (1–3 and 5–7).