Temporal β-diversity decomposition: Insights into fish biodiversity dynamics in the Moroccan South Atlantic

Abstract

Understanding the various aspects of temporal β-diversity and their relationships can profoundly enhance the knowledge of the intricate dynamics of biodiversity over temporal scales. In this study, we examined extensive data on fish in the Moroccan South Atlantic, to quantify taxonomic and functional temporal β-diversity over three five-year periods, determine the relative contributions of turnover and nestedness to each facet, and elucidate the relationship between taxonomic and functional temporal β-diversity including their components using temporal and spatial comparisons. Our findings revealed a complex relationship between taxonomic and functional temporal β-diversity, with decoupled variation often observed. Furthermore, the predominant component of functional temporal β-diversity was functional nestedness, while species turnover had a greater impact on taxonomic temporal β-diversity. A noteworthy observation was the significant fluctuation in the turnover and nestedness components, despite consistent temporal β-diversity. These insights underscore the pivotal role of temporal β-diversity decomposition and advocate for the integration of functional aspects in temporal biodiversity research to provide additional key indicators for biodiversity sustainable management.