Aim: Biodiversity across different scales provides multidimensional insurance for ecosystem functioning. Although the positive effects of local scale (α-diversity) biodiversity on ecosystem multifunctionality are widely accepted, species turnover across communities (β-diversity) which is often an important driver of ecosystem functioning did not receive the same attention. This study broadens the understanding of how multiple attributes of biodiversity maintain ecosystem multifunctionality from local to regional scales, across diverse environmental gradients.

Location: North-eastern China.

Time period: 2017.

Major taxa studied: Woody plants.

Methods: We estimate ecosystem multifunctionality using both averaging and modified multiple thresholds (50%, 70% and 90%) approaches. Multiple dimensions of biodiversity across varying spatial scales were measured within the framework of Hill‒Chao numbers. Linear and nonlinear models were used to evaluate the optimal patterns of multifunctionality and biodiversity along the latitude. Using variance decomposition, structural equation modeling and linear mixed models, we explored how multiple attributes of tree diversity at varying spatial scales affect multifunctionality, and how these relationships are modulated by environmental drivers.

Results: Our results show that multifunctionality decreased with increasing latitude, mirroring the pattern of tree diversity along latitudinal gradients. Phylogenetic β-diversity and species α-diversity emerged as crucial diversity indices for sustaining multifunctionality in these temperate forests. Soil and climatic conditions had either direct effects on multifunctionality, or indirect ones mediated by tree diversity. Environmental heterogeneity played a pivotal role in maintaining high levels of multifunctionality, exerting influence both directly and indirectly via phylogenetic β-diversity.

Main conclusions: This study underscores the positive effects of biodiversity on multifunctionality across multiple dimensions. Based on our findings, we conclude that any design of a forested landscape that is aimed at maximizing multifunctionality should consider maintaining high local diversity as well as forest community heterogeneity at varying scales.