Lichen Richness and Composition Patterns along Altitudinal gradients and Land use types in the Manaslu Conservation Area, Central Nepal

Abstract

Lichens, the mutualistic association betweenan alga (green and/or blue green) and a fungus are the most successful symbiotic organisms in nature. Nepal is rich in biodiversity. In comparison to higher plants, research work on lichen is very scanty. In the present study selected Manaslu Conservation Area. Though the Manaslu Conservation Area (MCA) is rich in biodiversity butis less explored. My study focused on species richness and composition of lichens in differentl and use types, altitudinal gradients and aspects. Four land use types selected areCroplandland, Meadow, Disturbed forest and Natural forest at five altitudinal gradients 2200 m, 2600m,3000m, 3400m and 3800m respectively.A total of 40 transect of 25 × 2.5 m each were laiddown in the study site. R-software was used to perform all the statistical analyses. Altogether 250species of lichens under 86 genera and 38 families have been reported by this study.I found significant difference in lichens species richness within different land use types(p≤0.00, df = 3) that may due to effect of habitat heterogeneity. Higher species richness of lichens has been recorded at natural forest, followed by meadows, exploited forest and cropland.Post hoc analysis (TukeyHSD) reveals that there was a significant difference in species richness of lichens between crop land land and meadow,cropland land and exploited forest,cropland land and natural forest whereas there is no significant difference observed among other land use types .Thus the main variation for the species richness of lichens indifferent land use type is mainly due to major difference in cropland with other three land use types that is meadow, exploited forest and natural forest. Different life forms of lichen showed significant difference with different land-use types. All four forms of lichens (crustose, foliose,fruti cose and leprose) were dominant in natural forests followed by meadows, exploited forests and cropland.There was no significant difference in species richness of lichens along altitudinal gradients(p≥0.05, df = 3) and aspects. It might be due to less number of altitudinal gradients and almost similar habitat types respectively.The DCA diagram for species composition showed a good dispersion among species along first two axes.Permutation result showed that altitude, natural forest and crop land land were important environmental variables to structure the composition of lichens. Key words: Altitude, Species richness, Land use types, DCA