Functional traits mediate the effect of land use on drivers of community stability within and across trophic levels.

Sperandii MG; Bazzichetto M; Götzenberger L; Moretti M; Achury R; Blüthgen N; Fischer M; Hölzel N; Klaus VH; Kleinebecker T; Neff F; Prati D; Bolliger R; Seibold S; Simons NK; Staab M; Weisser WW; de Bello F; Gossner MM

Abstract

Understanding how land use affects temporal stability is crucial to preserve biodiversity and ecosystem functions. Yet, the mechanistic links between land-use intensity and stability-driving mechanisms remain unclear, with functional traits likely playing a key role. Using 13 years of data from 300 sites in Germany, we tested whether and how trait-based community features mediate the effect of land-use intensity on acknowledged stability drivers (compensatory dynamics, portfolio effect, and dominant species variability), within and across plant and arthropod communities. Trait-based plant features, especially the prevalence of acquisitive strategies along the leaf-economics spectrum, were the main land-use intensity mediators within and across taxonomic and trophic levels, consistently influencing dominant species variability. Functional diversity also mediated land-use intensity effects but played a lesser role. Our analysis discloses trait-based community features as key mediators of land-use effects on stability drivers, emphasizing the need to consider multi-trophic functional interactions to better understand complex ecosystem dynamics.