Soil biopores formed by burrowing earthworms serve as preferential pathways for water flow and aeration 2. Subterranean activity by earthworms influences soil structure and provides numerous ecosystem services 1. The mechanistic model delineates the potential for earthworm migration via connectivity of hospitable sites and highlights regions sensitive to climate. Earthworm activity is strongly constrained by seasonal dynamics that vary across latitudes largely due to soil hydromechanical status.

We include additional constraints that exclude earthworm activity such as freezing temperatures, low soil pH, and high sand content to develop the first predictive global map of earthworm habitats in good agreement with observed earthworm occurrence patterns.

A mechanistic biophysical model is developed here to link the biomechanical limits of earthworm burrowing with soil moisture and texture to predict soil conditions that permit bioturbation across biomes. Hence, their activity is constrained by soil hydromechanical conditions that permit deformation at earthworm’s maximal hydroskeletal pressure (≈200kPa). Earthworms use their flexible hydroskeleton to burrow and expand biopores. Earthworm activity modifies soil structure and promotes important hydrological ecosystem functions for agricultural systems.

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