Fig. 3
Conceptual model of the processes involved in the assembly of local belowground communities. The model reflects our modelling strategy. At large scales, dispersal determines whether a species colonises an environmentally suitable patch. Nematodes are not much dispersal limited. Environment is therefore filtering species from broader to smaller scales. In the patch, there might be local environmental heterogeneity but also interaction with other species, which either were already resident or may colonise the patch in a second moment. Species feeding preferences might not overlap (Eudorylaimus–Plectus; Eudorylaimus–Scottnema: see Gaussian curves of different colours), which makes local coexistence more probable. Or, species feeding preferences might overlap (Scottnema–Plectus), which might imply either local competitive exclusion and segregation or, in some cases local coexistence via stabilising mechanisms
