Energy and physiological tolerance explain multi-trophic soil diversity in temperate mountains

Aim – Although soil biodiversity is extremely rich and spatially variable, both in terms of species and trophic groups, we still know little about its main drivers. Here, we contrast four long-standing hypotheses to explain the spatial variation of soil multi-trophic diversity: energy, physiological tolerance, habitat heterogeneity, and resource heterogeneity.
Location – French Alps
Methods – We built on a large-scale observatory across the French Alps (Orchamp) made of seventeen elevational gradients (~90 plots) ranging from low to very high altitude (280 - 3160 m), and encompassing large variations in climate, vegetation and pedological conditions. Biodiversity measurements of 36 soil trophic groups were obtained through environmental DNA metabarcoding. Using a machine learning approach, we assessed 1) the relative importance of predictors linked to different ecological hypotheses in explaining overall multi-trophic soil biodiversity, and 2) the consistency of the response curves acro...