Patterns and drivers of avian taxonomic and phylogenetic beta diversity in China vary across geographical backgrounds and dispersal abilities.

Geographical background and dispersal ability may strongly influence assemblage dissimilarity; however, these aspects have generally been overlooked in previous large-scale beta diversity studies. Here, we examined whether the patterns and drivers of taxonomic beta diversity (TBD) and phylogenetic beta diversity (PBD) of breeding birds in China vary across (1) regions on both sides of the Hu Line, which demarcates China's topographical, climatic, economic, and social patterns, and (2) species with different dispersal ability. TBD and PBD were calculated and partitioned into turnover and nestedness components using a moving window approach. Variables representing climate, habitat heterogeneity, and habitat quality were employed to evaluate the effects of environmental filtering. Spatial distance was considered to assess the impact of dispersal limitation. Variance partitioning analysis was applied to assess the relative roles of these variables. In general, the values of TBD and PBD were high in mountainous areas and were largely determined by environmental filtering. However, different dominant environmental filters on either side of the Hu Line led to divergent beta diversity patterns. Specifically, climate-driven species turnover and habitat heterogeneity-related species nestedness dominated the regions east and west of the line, respectively. Additionally, bird species with stronger dispersal ability were more susceptible to environmental filtering, resulting in more homogeneous assemblages. Our results indicated that regions with distinctive geographical backgrounds may present different ecological factors that lead to divergent assemblage dissimilarity patterns, and dispersal ability determines the response of assemblages to these ecological factors. Identifying a single universal explanation for the observed pattern without considering these aspects may lead to simplistic or incomplete conclusions. Consequently, a comprehensive understanding of large-scale beta diversity patterns and effective planning of conservation strategies necessitate the consideration of both geographical background and species dispersal ability.

[Resident breeding bird responses to wind turbines: A functional and phylogenetic perspective]. / 基于功能和谱系视角分析繁殖留鸟对风机的响应.

As a clean and green renewable energy source, wind power attracts more and more attention globally, and rapidly expands its use scale. There are conflicts between wind power development and bird protection. The impacts of wind farms on birds is a hot topic for ecologists and conservationists. To estimate the effects of wind turbines on avian species diversity and their functional and phylogenetic diversity, we conducted line transect surveys in January, March, April and May 2019. Thirty-two line transects were divided into four gradients according to the distance from the wind turbines, i.e., 100-300 m (6 transects), 300-500 m (13 transects), 500-700 m (8 transects), >700 m (5 transects). The results showed that a total of 76 resident breeding birds were recorded, belonging to 11 orders and 31 families. Passeriformes and Timaliidae had the highest species richness (53 and 12 species, respectively). Bird species richness, functional richness (FRic), and phylogenetic diversity (Faith's PD) were increased with increasing distance from the wind turbines. Specifically, bird richness, FRic and phylogenetic diversity increased little within 500 m of the wind turbines, whereas a significant increase occurred over 500 m from wind turbines. The community-weighted mean of dispersal ability showed an increasing trend with distance from the wind turbines. The standardized effect size of both mean pairwise functional/phylogenetic distance (SES.MFD and SES.MPD) were less than 0 in all transects, with about half of which being significantly lower than expected at random. This finding suggested that the impacts of wind farms on bird species, functional and phylogenetic diversity occurred within 500 meters from wind turbines, with a pattern of functional and phylogenetic clustering. The impacts of wind turbines on birds were multi-dimensional. It is therefore difficult to provide complete perspective on assessing the impacts of wind farms on birds when only considering species diversity.