Elevational patterns of amphibian functional and phylogenetic structures in eastern Nepal Himalaya

Abstract

Aim Exploring the mechanism underlying community assembly processes is considered as one of the central topics for biogeography. As one of the biodiversity hotspots, Nepal Himalaya has attracted increasing attention during the past decade. However, the main processes shaping amphibian assemblages in this area are still unclear. Here, we examined the elevational patterns of amphibian functional and phylogenetic structures to understand the main mechanism driving amphibian assemblages along an elevational gradient in eastern Nepal Himalaya. Location Eastern Nepal Himalaya. Methods Amphibian taxonomic, functional and phylogenetic diversity were calculated, and their responses to the increasing elevations were investigated based on the linear regressions. The environmental determinants of amphibian diversity were revealed based on the incorporation of generalized linear models and hierarchical partitioning analyses. In addition, the mechanism driving amphibian assemblages from low to high elevations was tested by calculating the mean pairwise functional distance and the mean pairwise phylogenetic distance indices. Results Amphibian taxonomic, functional and phylogenetic diversity had contrast responses to the increasing elevations, which were strongly determined by variables such as air temperature, the number of trees, leaf litter cover and water pH. Interestingly, the trends of amphibian functional and phylogenetic diversity along an elevational gradient can be changed after controlling the effects of species richness. Moreover, determining process played a dominant role in shaping amphibian assemblages with the increasing elevations. Conclusions Our results revealed the elevational patterns of amphibian functional and phylogenetic structures in eastern Nepal Himalaya, associated with the change in environmental variables. We also highlighted the dominant role of determining process in shaping amphibian assemblages. Overall, our results can help ecologists and managers better understand and formulate amphibian diversity conservation. In addition, our results also enriched the fundamental knowledge to understand the general patterns of community assembly rules in montane ecosystems.

Spatial Patterns of Species Diversity of Amphibians in a Nature Reserve in Eastern China

“…The variations of phylogenetic diversity with elevations were variable across different taxa in different mountains [ 60 ]. In our studied nature reserve, the PD values of amphibians also showed a hump-shaped relationship with elevation, which was similar to other reported mountainous areas, such as the eastern Himalayas of Nepal [ 20 ]. Interestingly, the elevations of 300–500 m seemed to have the maximum PD value, which could be explained by the presence of evolutionary key species which are narrowly distributed along low elevations [ 20 ].…”

“…To create effective conservation schemes and management strategies, it is important to know the various community structures that underpin and support the present biodiversity in the ecosystem [ 2 ]. Most studies focus only on the taxonomic element of species, regarding species as ecologically identical entities when analyzing how communities are formed [ 20 ]. Taxonomic diversity indices (e.g., species richness, Simpson index, and Shannon–Weiner index) reflect certain characteristics of species diversity to some extent, such as the abundance of species and the uniformity of their distribution [ 21 ].…”

Multiple β‐diversity patterns and the underlying mechanisms across amphibian communities along a subtropical elevational gradient

“…Community structure and its assembly mechanisms are not constant across mountain ecosystems (Du et al, 2021; Wang et al, 2022; Zhao et al, 2022). We tested the variations in standardized β‐diversity among communities to assess the potential assembly processes.…”

“…Amphibian communities exhibit diverse patterns in response to environmental and geographical gradients (Dalmolin et al, 2019; Leao‐Pires et al, 2018; Zhao et al, 2022). Elevational distance when considered a proxy of the dispersal limitation (Basham et al, 2019), greatly influenced species replacement and loss/gain among communities.…”

New progress in exploring the mechanisms underlying extraordinarily high biodiversity in global hotspots and their implications for conservation

“…Still in Asia, Zhao et al (2022) showed that both elevation and environmental variations (e.g. air temperature, the number of tree stumps, the number of trees showing looping, the number of trees and water pH) drive the spatial distribution of amphibian functional and phylogenetic diversity patterns in eastern Nepal Himalaya.…”