AUTHOR=Yao Zhenyu , Xin Yue , Ma Zhaoxia , Zhao Liqing , Mu Wenkui , Guo Jianying , Ali Arshad 

TITLE=Plant beta-turnover rather than nestedness shapes overall taxonomic and phylogenetic beta-diversity triggered by favorable spatial–environmental conditions in large-scale Chinese grasslands

JOURNAL=Frontiers in Plant Science

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2024.1285787

DOI=10.3389/fpls.2024.1285787

ISSN=1664-462X

ABSTRACT=<sec><title>Introduction</title><p>Although it is widely acknowledged that biodiversity maintains plant community assembly processes, exploring the patterns and drivers of beta-diversity (<italic>β</italic>-diversity; species variation among local plant communities) has received much less attention compared to alpha-diversity (<italic>α</italic>-diversity; species variation within a local plant community). Here, we aim to examine the patterns and spatial–environmental drivers of taxonomic and phylogenetic <italic>β</italic>-diversity, and their components such as species turnover and nestedness, in large-scale <italic>Leymus chinensis</italic> grassland communities.</p></sec><sec><title>Methods</title><p>We collected plant community data from 166 sites across widely distributed <italic>L. chinensis</italic> communities in northern China, and then calculated the taxonomic and phylogenetic <italic>β</italic>-diversity indices (overall, turnover and nestedness) using a pairwise dissimilarity approach. To assess the effects and to explain the variation in the patterns of <italic>β</italic>-diversity, we collected data on geospatial, climate and soil conditions. We applied descriptive statistics, Mental correlations, and multiple linear regression models to assess the patterns and spatial–environmental drivers of <italic>β</italic>-diversity.</p></sec><sec><title>Results</title><p>The <italic>β</italic>-turnover, as compared to <italic>β</italic>-nestedness, exhibited a predominant influence, constituting 92.6% of the taxonomic <italic>β</italic>-diversity and 80.4% of the phylogenetic <italic>β</italic>-diversity. Most of the spatial–environmental variables were significantly positively correlated with the overall taxonomic and phylogenetic <italic>β</italic>-diversity and <italic>β</italic>-turnover, but not with <italic>β</italic>-nestedness. Climatic factors such as MAP and MAT were the strongest predictors of both taxonomic and phylogenetic <italic>β</italic>-diversity and <italic>β</italic>-turnover. The variance partitioning analysis showed that the combined effects of spatial and environmental factors accounted for 19% and 16% of the variation in the taxonomic and phylogenetic <italic>β</italic>-diversity (overall), 17% and 12% of the variation in the <italic>β</italic>-turnover, and 7% and 1% of the variation in the <italic>β</italic>-nestedness, respectively, which were higher than independent effects of either spatial or environmental factors.</p></sec><sec><title>Discussion</title><p>At larger spatial scales, the turnover component of <italic>β</italic>-diversity may be associated with the species complementarity effect, but dominant or functionally important species can vary among communities due to the species selection effect. By incorporating <italic>β</italic>-diversity into grassland management strategies, we can enhance the provision of vital ecosystem services that bolster human welfare, serving as a resilient barrier against the adverse effects of climate change at regional and global scales.</p></sec>