Plant and Soil Biodiversity Support Different Dimensions of Ecosystem Functioning after Decades of Subtropical Forest Rewilding

Abstract

Subtropical ecosystems are important biodiversity hotspots to global change, where plant and soil biodiversity play crucial roles in supporting multiple ecosystem functions simultaneously (i.e., multifunctionality). However, the relative contribution of plant and soil biodiversity in supporting multifunctionality after decades of forest rewilding remains largely unclear. Here, we conducted a standardized field survey in a subtropical forest after 31-year forest rewilding to explore how plant and soil biodiversity (i.e., bacteria, arbuscular mycorrhizal (AM) fungi, ectomycorrhizal (EcM) fungi, and saprotrophic fungi) contribute to explain ecosystem multifunctionality. We found that both plant and soil biodiversity were significantly correlated with ecosystem functions, but contributed to different dimensions of ecosystem functions. Specifically, plant diversity significantly supported ecosystem functional dimension #1 dominated by plant-soil mutualism and soil C, whereas soil biodiversity mainly explained ecosystem functional dimension #2 linked with soil macronutrients and micronutrients. Together, our work provides insights that plant and soil biodiversity play complementary roles in supporting different dimensions of ecosystem functioning, which is critical for restoration and protection efforts in subtropical forests, and thus for human well-being.

Keywords: forest restoration, plant biodiversity, microbial biodiversity, biodiversity-ecosystem functioning, subtropical forest