Biodiversity has become a subject of major interest since twenty years, giving rise to scientifc works, international conferences and discussions. Fears concerning the decline of life diversity take a strong place in the current environmental stakes. Without denying the reasons that justify such a concern, this paper focuse on the territorial aspects of the topic. The naturalist approach seems partly inadequate to deal with the matter in a spatial and temporal point of view. Taking in account "natural” and social areas enable to demonstrate the relativity of the matter and the diversity of cases. This paper consider biodiversity partly as a result of social history and thus, as a temporal process with period of decline alternating with peri...