TY - JOUR

T1 - Tree diversity and mycorrhizal type co-determine multitrophic ecosystem functions

AU - Yi, Huimin

AU - Eisenhauer, Nico

AU - Austen, Jan Christoph

AU - Rebollo, Roberto

AU - Ray, Tama

AU - Bönisch, Elisabeth

AU - von Oheimb, Goddert

AU - Fichtner, Andreas

AU - Schuldt, Andreas

AU - Patoine, Guillaume

AU - Ferlian, Olga

N1 - Funding Information: We thank Julius Quosh for helping maintaining the field site and organizing the annual tree inventory. Moreover, we acknowledge Yuanyuan Huang for the support in statistical analysis and for curating the MyDiv database. We acknowledge constructive comments by three anonymous reviewers who helped us to improve our manuscript. We thank Max Lakanen's assistance in refining the language of the manuscript. T. Ray is member of the International Research Training Group TreeDì jointly funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), grant number 319936945/GRK2324 and the University of Chinese Academy of Sciences (UCAS). R. Rebollo was supported by Conacyt (Mexico), grant number 2019‐000003‐01EXTF‐00226 and the German Academic Exchange Service (DAAD), agreement number 57504644. This work was funded by the German Research Foundation in the frame of the Gottfried Wilhelm Leibniz Prize (Ei 862/29‐1). Further support came from the German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, funded by the German Research Foundation (FZT 118). The Graphical Abstract was created with BioRender.com . Open Access funding enabled and organized by Projekt DEAL. Publisher Copyright: © 2024 The Authors. Journal of Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

PY - 2024/3

Y1 - 2024/3

N2 - The relationship between biodiversity and multitrophic ecosystem functions (BEF) remains poorly studied in forests. There have been inconsistent reports regarding the significance of tree diversity effects on ecosystem functions, which may be better understood by considering critical biotic interactions of trees. This study investigates the role of tree-mycorrhizal associations that may shape forest BEF relationships across multiple ecosystem functions. We used a field experiment (MyDiv) that comprises 10 deciduous tree species associated with either arbuscular mycorrhizal (AM) or ectomycorrhizal (EcM) fungi to create gradients in species richness (1, 2, 4 species) and different mycorrhizal communities (only AM-species [AM fungi associated tree species] or EcM-species [EcM fungi associated tree species], or a combination of both). We investigated the effects of tree species richness and mycorrhizal types on crucial multitrophic ecosystem functions (foliage damage, predation [using artificial caterpillars] and soil fauna feeding activity [~0–10 cm]) and assessed how these effects were mediated by stand characteristics. Overall, we found that tree species richness and mycorrhizal types strongly affected multitrophic ecosystem functions. Compared to monocultures, 4-species mixtures with both mycorrhizal types experienced significantly lower foliage damage. The mixtures of EcM-species supported significantly higher predation (i.e. a greater proportion of artificial caterpillars being attacked), and this effect strengthened with tree species richness. The effects of tree species richness on soil fauna feeding activity were negative across all mycorrhizal types in the lower soil layer. Moreover, we showed that tree diversity effects were mediated by above-ground tree biomass, vertical structural complexity and leaf quality, with the dominating mechanisms largely depending on the mycorrhizal types. Synthesis. Tree species richness affected multitrophic ecosystem functioning by (1) directly decreasing the proportion of foliage damage in the communities with both mycorrhizal types, where AM-species benefited from mixing with EcM-species, and (2) increasing predation rates via changes in the vertical structural complexity in mixtures of EcM-species. Our results highlight the importance of considering mycorrhizal types for managing well-functioning mixed-species forests and contribute to broadening the mechanistic understanding of the context-dependent BEF relationships in forests.

AB - The relationship between biodiversity and multitrophic ecosystem functions (BEF) remains poorly studied in forests. There have been inconsistent reports regarding the significance of tree diversity effects on ecosystem functions, which may be better understood by considering critical biotic interactions of trees. This study investigates the role of tree-mycorrhizal associations that may shape forest BEF relationships across multiple ecosystem functions. We used a field experiment (MyDiv) that comprises 10 deciduous tree species associated with either arbuscular mycorrhizal (AM) or ectomycorrhizal (EcM) fungi to create gradients in species richness (1, 2, 4 species) and different mycorrhizal communities (only AM-species [AM fungi associated tree species] or EcM-species [EcM fungi associated tree species], or a combination of both). We investigated the effects of tree species richness and mycorrhizal types on crucial multitrophic ecosystem functions (foliage damage, predation [using artificial caterpillars] and soil fauna feeding activity [~0–10 cm]) and assessed how these effects were mediated by stand characteristics. Overall, we found that tree species richness and mycorrhizal types strongly affected multitrophic ecosystem functions. Compared to monocultures, 4-species mixtures with both mycorrhizal types experienced significantly lower foliage damage. The mixtures of EcM-species supported significantly higher predation (i.e. a greater proportion of artificial caterpillars being attacked), and this effect strengthened with tree species richness. The effects of tree species richness on soil fauna feeding activity were negative across all mycorrhizal types in the lower soil layer. Moreover, we showed that tree diversity effects were mediated by above-ground tree biomass, vertical structural complexity and leaf quality, with the dominating mechanisms largely depending on the mycorrhizal types. Synthesis. Tree species richness affected multitrophic ecosystem functioning by (1) directly decreasing the proportion of foliage damage in the communities with both mycorrhizal types, where AM-species benefited from mixing with EcM-species, and (2) increasing predation rates via changes in the vertical structural complexity in mixtures of EcM-species. Our results highlight the importance of considering mycorrhizal types for managing well-functioning mixed-species forests and contribute to broadening the mechanistic understanding of the context-dependent BEF relationships in forests.

KW - biodiversity-ecosystem functioning

KW - biotic interactions

KW - herbivory

KW - mycorrhizal type

KW - MyDiv

KW - predation

KW - soil fauna feeding activity

KW - stand characteristics

KW - Engineering

UR - http://www.scopus.com/inward/record.url?scp=85181961257&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/c9c44a31-92ff-35e8-8388-9bb054a62c87/

U2 - 10.1111/1365-2745.14252

DO - 10.1111/1365-2745.14252

M3 - Journal articles

AN - SCOPUS:85181961257

VL - 112

SP - 528

EP - 546

JO - Journal of Ecology

JF - Journal of Ecology

SN - 0022-0477

IS - 3

ER -