Mountain soil food webs shaped by the interplay between habitat and pedoclimatic conditions

Abstract

Our knowledge of the factors influencing the distribution of soil organisms is limited to specific taxonomic groups. Consequently, our understanding of the drivers shaping the entire soil food web is constrained. To address this gap, we conducted an extensive soil biodiversity monitoring program in the French Alps, using environmental DNA to obtain multi-taxon data from 418 soil samples. The spatial structure of resulting soil food webs varied significantly between and within habitats. From forests to grasslands, we observed a shift in the abundance of trophic groups from fungal to bacterial feeding channels, reflecting different ecosystem functioning. Furthermore, forest food webs were more strongly spatially structured which could only partly be explained by abiotic conditions. Grassland food webs were more strongly driven by plant community composition and soil characteristics. Our findings provide valuable insights into how climate and land use changes may differentially affect soil food webs in mountains.