Résumé
In cities of industrialized countries, urban agriculture is expanding in the townscape, both in surface and diversity of forms. In those highly populated areas a major challenge is to control plant pests without using pesticides. In rural context, soil epigeic generalist predators (EGP; mainly arthropods such as ground beetles or spiders) have an important role in biocontrol but little is known about their real impact and the subsequent ecosystem service in urban farms.The aim of this study is to better understand the biocontrol provided by EGP on various forms of urban farms. We surveyed 9 urban farms located in Paris and close suburb among (i) productive at ground-level, (ii) productive on rooftops and (iii) non-productive gardens. We measured the predation activity studying the consumption of sentinel eggs of the Mediterranean flour moth (Ephestia kuehniella) and pupae of the Housefly (Musca domestica) set on the ground. We also analyzed the density of potential EGP using pitfall traps.This study gave new insights about the biocontrol service in urban context and argue for the acknowledgement of EGP as ecosystem providers for urban farms