Long-term effects of trampling on Atlantic Heathland in Brittany (France): resilience and tolerance in relation to season and meteorological conditions Original Research Article

In recent decades, human trampling has become an important factor in the degradation of Atlantic heathlands. In a previous paper we showed that short-term responses of heathland to trampling were dependant on environmental parameters such as season and weather conditions (Gallet, S., Rozé, F., 2001b. Resistance of Atlantic Heathlands to trampling in Brittany (France): influence of vegetation type, season and weather conditions. Biological Conservation, 97, 189–198). Here, long term responses of experimental trampling, characterised by the resilience and the tolerance of communities and plants appear also dependant on these parameters. Dry and mesophilous heathlands are more tolerant to trampling in winter than in summer. In the case of mesophilous heathland, this is linked to high plant resilience, especially of Erica ciliaris. In summer, influence of meteorological conditions at the time of trampling depend on the species; indeed wet conditions lead to lower tolerance of Erica cinerea but to higher tolerance of E. ciliaris. Management of tourist pressure on natural or semi-natural sites must take visitors on the more tolerant communities, so it must take into account the variability of tolerance to trampling of the different types of vegetation present and needs to be adaptable to environmental conditions.