Relative importance of deterministic and stochastic processes for beta diversity of bird assemblages in Yunnan, China

Xuelian He,Calum Brown,Luxiang Lin

doi:10.1002/ecs2.3545

Abstract

AbstractEvaluating the relative importance of deterministic and stochastic processes underlying taxonomic and functional beta diversity is crucial in community ecology, because it can reveal the dominant processes of community assembly. However, studies of bird communities remain rare and of limited spatial extents. In this study, we described the taxonomic and functional beta diversity patterns of 32 passerine bird assemblages of Yunnan Province, China. We constructed null models based on observed species beta diversity and used multiple regressions on distance matrices to evaluate the relative contributions of deterministic and stochastic processes to passerine bird assemblage dissimilarity. Our results showed significant geographic distance decay in taxonomic and functional similarity, with passerine bird assemblages located in the northwest and southwest of the province having higher functional beta diversity values than expected. Environmental distance and geographic distance explained a similar amount taxonomic beta diversity, but environmental distance explained much more functional beta diversity. Our results suggest that both deterministic and stochastic processes drive taxonomic beta diversity, but that deterministic processes, particularly environmental filtering, play a dominant role in driving functional beta diversity of passerine bird assemblages at sub‐national scale.

Highlights

Deterministic and stochastic processes are thought to be important in governing the structure of natural communities
We focused on the following questions: (1) whether the taxonomic and functional dissimilarity increases with increasing geographic distance; (2) whether the functional dissimilarity between assemblages from extreme habitats and other habitats are significantly higher than expected; and (3) whether spatial or climatic explanations of taxonomic and functional beta diversity are significantly different
Taxonomic beta diversity was positively correlated with geographic distance

Summary

Introduction

Deterministic and stochastic processes are thought to be important in governing the structure of natural communities. Two communities may have both high taxonomic and functional beta diversity if their habitats are connected but in different environmental conditions (Smith and Wilson 2002, Fukami et al 2005, Dalmolin et al 2019). Integrating these two aspects of beta diversity could help to achieve better understanding of the dominant processes in community assembly (Siefert et al 2013, Dalmolin et al 2019)

Methods

Results

Discussion

Conclusion