Oliver Mitesser, Marc W Cadotte, A. Mori, Fons van der Plas, Anne Chao, Julia Rothacher, Claus Bässler, Mirjana Bevanda, Peter H W Biedermann, Pia M. Bradler, Antonio Castañeda-Gómez, Orsi Decker, Benjamin M Delory, Sebastian Dittrich, Heike Feldhaar, Andreas Fichtner, Alexander Kreis, Lisa Köstler-Albert, Ludwig Lettenmaier, Goddert von Oheimb, Luisa Pflumm, Kerstin Pierick, Jakob Schwalb‐Willmann, Simon Thorn, Leah Vogelfänger, Wolfgang Weisser, Martin Wegmann, Clara Wild, Jörg Müller
Metacommunity theory has expanded our understanding of how spatial dynamics and local interactions influence species communities. Different assembly archetypes, reflecting different roles of species differences, habitat differences, and dispersal have been described, but we lack empirical studies specifically in terrestrial habitats testing which archetype is most important. In a replicated design, we experimentally enhanced structural between-patch heterogeneity in homogeneous production forests and developed a statistical framework controlling for sample incompleteness to detect different metacommunity processes. Meta-analyses on > 100 K individuals of > 1.3 K beetle species showed an increase of ~60 species in heterogenized forests at γ-level promoted by increasing α-diversity consistent with the mass-effect and an increase of β-diversity by ~10% supporting species-sorting. Additionally, we tested β-deviations from random assembly as a proxy of neutral processes. Findings indicate that enhancing structural heterogeneity can shift forests from patch-dynamics dominance towards mass-effect and species-sorting, offering a promising pathway to restore biodiversity in managed landscapes.