The introduction of terrestrial platyhelminthes, recognized as superpredators of soil invertebrate fauna, may represent a threat to earthworms and the numerous ecosystem services that they provide. Based on the functional classification of ecosystem engineers7, earthworms can be considered, in the soil, as (i) structural engineers; (ii) chemical engineers and (iii) bioturbators. The structural function refers to the creation of biogenic structure (aggregates, burrows) and the chemical one to earthworm involvement in nutrient cycling through their influence on the decomposition and mineralization of litter by breaking down organic matter and their influence on the gas and water exchange or nutrient transfer in the soil. Earthworms are also recognized as one of the three top bioturbators in soils, together with ants and termites8. By significantly modifying the physical, chemical and biological properties of the soil profile; earthworms play a key role in determining the biodiversity of the whole ecosystem, as they influence the habitat and activities of many other organisms (plants, animals and micro-organisms).

Predicting the impact of the presence of a newly introduced predator is particularly challengingbecause of the need to simultaneously consider many anthropogenic and ecological factors18. Our final objective is to develop an original qualitative model aiming at exhaustively describing soil ecosystem dynamics following platyhelminthes introduction. We propose to use discrete models inspired from theoretical computer sciences for their ability to model changes in the structure of interactions networks19. This requires determining the ecological components (biotic, abiotic and anthropogenic) and all the interactions that are necessary to understand the invaded ecosystem.