Species Richness Capture Plant Functional and Phylogenetic Diversity Variations Along Different Ecosystems on the Hillsides of Damavand Mountain (Iran)

Abstract

Aims Plants vary in their functional traits and thus in their preference towards edaphic conditions. Plants displaying tougher, long-living leaves, which better conserve nutrients in the tissues, are expected to grow better in acidic soils, which are frequently nutrient poor. Methods We used a trait-based approach, quantifying variations in the Leaf-height-seed (LHS) scheme and functional and phylogenetic indices in semi-arid communities from three different habitats (grasslands, shrubland and mixed habitats). Three traits, including specific leaf area (SLA), Plant height (H) and Seed Mass (SM), in 350 plots across the three habitats in the southern hillsides of Damavand Mountain. We only included the species that occurred in more than 20 plots throughout the dataset for the following analyses (i.e., 44 species). We calculated at the plot scale, community weighted means (CWM) for each trait, species richness, Faith’s phylogenetic diversity index (PD), functional richness (Frich), functional and phylogenetic mean pairwise dissimilarities (MPD) and nutrient concentration. Results The results showed that the higher soil nutrient concentration and pH were significant and positive related with species and functional richness and Faith´s phylogenetic distance, while not significant results were obtained for any functional trait at community level (SLACWM, VHCWM and SMCWM) or for the functional and phylogenetic mean pairwise distance.Conclusiones In addition, the phylogenetic and functional patterns responded more to the taxonomic richness variations than to trait-based assembly processes.