Modern agricultural areas are shaped into landscapes with an impoverished heterogeneity. In this areas, habitat loss and fragmentation are the major concern that threaten biologically diverse habitats and its species. Functional ecological networks are now implemented by the law on Nature Conservation (1997) in order to preserve and restore vulnerable plant populations and to increase biodiversity. These conservation programs need a scientific framework in order to understand the population dynamics of 'tool species' in isolated and degraded habitats. In this study we investigate the impact of fragmentation and isolation on the reproductive success, population dynamics and population vitality in three Primula-species (Primula vulgaris, P. veris and P. elatior).