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Abstract: Macrolichen community structure and traits were examined across a high elevation gradient in southwestern British Columbia. To our knowledge, the current study is the first to examine lichen phylogeny and community traits along a gradient of elevation. Samples were collected from 13 plots, every 50m from 1200 to 1800m at Joffre Lakes Provincial Park. Species richness within this zone had a unimodel distribution from low to high elevation and peaked at an intermediate elevation. Canonical correspondence analysis (CCA) confirmed that a distinct lichen community structure and assemblage of lichens is represented across the gradient of elevation. The covariate for lichen phylogeny explained 9% of the variation in community assemblage along the gradient of elevation. Lichen traits explained 91% of the variation in community assemblage. The first CCA axis distinguishes between alpine and forest lichen communities, and identified important microhabitats and traits used to explain variation in the species associations. The second CCA axis makes a distinction between higher and lower elevations and is strongly correlated with variables such as the presence of specific microhabitats (i.e. rock, wood, or bark), and lichen traits. Within the elevation range assessed, the analysis indicated three distinct lichen communities, one in alpine ecosystems, one in higher elevations forests and one in mid elevation forests. These results provide forest managers with an increased understanding of lichen community structure across elevation gradients and of indicator species and their associated traits, which can assist with management strategies that include the preservation of biodiversity. [Copyright &y& Elsevier]

Biodiversity surveys were conducted in 13, 10×50 m2 plots located between 1400 to 3700 m above mean sea level in a range of habitats in temperate mixed Oak and Coniferous forests through sub-alpine to the alpine grasslands in Chamoli district of Uttaranchal state in the Indian Garhwal Himalaya. Cross-taxon congruence in biodiversity (α-diversity and β-diversity) across macrolichens, mosses, liverworts, woody plants (shrubs and trees) and ants was investigated, so as to examine the extent to which these groups of organisms can function as surrogates for each other. Although woody plants provided a major substrate for macrolichens and mosses, there was no species-specific association between them. Woody plant species richness was highly positively correlated with mosses (r2=0.63, P<0.001), but the relationship was not particularly very strong with lichens and liverworts. While there was a significant correlation in the species turnover (β-diversity) of macrolichens with mosses (r2=0.21, P<0.005), the relationship was relatively poor with the woody plants. On the other hand, negative correlations emerged in the species richness of ants with those of macrolichens, mosses and woody plants (r2=−0.44, P<0.05), but most of the complementarity (turnover) relationships among them were positive. Since diversity between taxonomic hierarchies within the group was consistently significantly positively correlated in all these taxa, the higher taxonomic categories such as genus and family may be employed as surrogates for rapid assessment and monitoring of species diversity. Although no single group other than macrolichens has emerged as a good indicator of changes in species richness in all other groups, some concordant relationships between them conform to the hypothesis that species assemblages of certain taxonomic groups could still be used as surrogates for efficient monitoring of species diversity in other groups whose distribution may further predict the importance of conserving overall biodiversity in landscapes such as the Garhwal Himalaya. [Copyright &y& Elsevier]