The bioporosphere and its role in soil functioning

Along with roots, soil macrofauna such as earthworms, ants, termites, beetles and myriapods dramatically alter the physical architecture of soil with strong effects on the distribution and connectivity of pores, and therefore on key ecological functions such as water dynamics, gas exchanges, soil organic matter decomposition or storage. While most of the literature has focused on the properties of galleries and show their large variability, much less is known about the other pores produced by soil fauna (e.g., those agented between or within biogenic aggregates or those located around galleries).

Using examples from studies carried out in tropical and temperate soils, I show that the ‘trait-based’ approach in soil biology offers interesting perspectives for understanding the properties of biopores, and as a consequence of the impacts of soil fauna on water dynamics and biogeochemical cycling. Second, I show that galleries are not as stable as we imagine, indicating the need to quantify their dynamics. Finally, I show that macrofauna influence also the architecture of small pores with consequences on the dynamics of soil organic matter and other properties. To conclude, I introduce the “bioporosphere” as a new concept to integrate the complex effects of soil fauna on its functions.