潮白河(北京段)大型底栖动物多维度多样性及群落稳定性特征OA

The Chaobai River basin,a biodiversity hotspot in Beijing,plays a crucial role in understanding the river's ecosystem and improving protection quality.This is achieved through studies on benthic macroinvertebrates,biodiversity and community sta-bility.In this study,44 sampling sites were established in the mountainous and plain sections of the Chaobai River basin,and sur-veys of benthic macroinvertebrates communities and their diversity were conducted in September 2020(autumn),December 2020(winter),April 2021(spring),and July 2021(summer).Utilizing the data obtained from these surveys,a comprehensive analy-sis was conducted to examine the spatiotemporal variations in the multidimensional biodiversity and community stability of benthic macroinvertebrates within the Beijing section of the Chaobai River basin.This analysis employed Pearson correlation coefficients and generalized linear models to explore the relationships between various biodiversity and community stability indices.The results indicated that the biodiversity and community stability of benthic macroinvertebrates in the Chaobai River exhibited no significant seasonal fluctuations,while pronounced differences were observed between mountainous and plain regions.The Margalef richness index and other species diversity indices were found to be elevated in the mountainous area,while the Pielou evenness index was reduced.The analysis of functional diversity indices indicated a greater abundance of both functional traits and redundant species in the mountainous section.Secondary productivity,turnover rate,and species competition intensity of benthic macroinvertebrates were lower in the mountainous area of the Chaobai River than in the plain area,while cohesion was higher,suggesting greater com-munity stability in the mountainous area.Pearson correlation analysis revealed significant correlations between different biodiversity indices,while correlations between indices representing community stability were weak and not significant.A correlation analysis was conducted between diversity and stability,with the findings indicating that a more uniform species distribution,higher species richness,and greater niche differentiation resulted in higher secondary productivity,a larger turnover rate,less intense species competition,and greater community cohesion.This,in turn,led to higher community stability.The most parsimonious models for community stability in both mountainous and plain areas favoured taxonomic and functional diversity to explain changes in benthic macroinvertebrates community stability in the Chaobai River.The most frequently selected option was functional divergence(FDiv),indicating that differences in species trait abundance and interspecific niche complementarity are key factors affecting benthic macroinvertebrates community stability in the Chaobai River.However,it was the model for secondary productivity in the plain area that exhibited comparatively high explanatory power;the other models demonstrated low explanatory power.This finding suggests that environmental factors may exert a greater influence on the stability of the benthic macroinvertebrates community in the Beijing section of the Chaobai River.