Lichens of Khaptad National Park, West Nepal

Abstract

Lichens are playing important role in ecosystems functioning and are widely recognized as excellent environmental indicators worldwide. However, very little is known about lichen communities and their importance in Nepal. Nepal is believed to have a rich lichen flora. This present study studied the lichen species diversity along the altitudinal gradient and effects of host species on its distribution. To fulfill these objectives present work was carried out in the Khaptad National Park, Western Nepal. Khaptad National Park is one of holy shrines in Nepal. Lichens were sampled along different forests found in Khaptad National Park from an altitude of 2200 m to 3200 m asl. A total of 98 plots, of 5 x 5 m v

2 area each, were laid down. The plots were laid 10 m away from the ridges of walking trail between every 200 m distance. A total of 49 plots sampled on each sides of the study area. Detrended Correspondence Analysis (DCA) and Canonical Correspondence Analysis (CCA) were performed to analyze the species composition and environmental relations through the R- software. A total of 47 lichen species belonging to 29 genera and 14 families were recorded. Among them Parmeliaceae was largest family with 17 species. Within the recorded lichens, 27 species were foliose, 10 crustose, 7 fruticose and 3 leprose. There were 40 species found growing on the tree bark which were called as corticolous groups. DCA first axis Eigen value was 0.72 with an axis length of 8.01 SD units indicating a complete species turnover along the major altitudinal gradient. This gave inferences that each of the plot got a high beta diversity along the altitude. The CCA ordination showed that there was about 13 % of the total variance explained by the measured environmental variables and remaining 87% was unknown. Total lichen species richness showed significant increasing pattern with the altitude. Furthermore the number of lichen species occured more on the Quercus tree towards the lower altitude may be its rough bark. At the higher altitude, high air moisture would have aided the higher number of lichen species in the Abies, Picea trees. Slope and aspects did not show significant relationship to the lichen richness. Thus it can be concluded that the altitude and host have a significant effect on the distribution of the lichens. Keywords: Khaptad National Park, lichen species diversity, Detrended correspondence analysis, Canonical correspondence analysis, altitudinal gradient, host species.