Biodiversity and ecosystem services: Complementary approaches for ecosystem management?

The concept of ecosystem services introduced a new view on the relationship between biodiversity and human well being. But are both concepts, biodiversity and ecosystem services, mutually beneficial? We will try to unravel part of this much debated question in three steps. Firstly, a general hypothesis describing the present link between biodiversity, ecosystem services and land use intensity is tested for the region of Flanders (13.682 km2). The spatial exercise illustrates that even in a densely populated area as Flanders (539 inhabitants/km2), scores for biodiversity and ecosystem services show a clear decline with an increase in land use intensity. Despite the overall congruence of the rough indicators of biodiversity and ecosystem services used in this exercise, the need for new indicators integrating key structural and functional aspects of the ecosystem is highlighted. In a second step a target scheme is proposed describing the relation between biodiversity and land use intensity, for the long-term future. In this conceptual framework the need for the conservation and restoration of biodiversity hot spots is emphasized. At the same time the importance of the search for an environmental ‘bottom line’ is stressed. What is the minimum amount of biodiversity needed to reach sustainable use? And what is the critical point for human impact beyond which society will largely depend on the import of ecosystem services to sustain or increase its well-being? In a third step, ecosystem management is used as a concept to bridge the gap between the present and the target scheme. Ecosystem management is divided into three focal zones. (1) For the remaining zones with a high biodiversity and a low intensity of land use, a biodiversity conservation based approach is needed. (2) For most rural areas with multifunctional uses and a good state as a future perspective, a focus on ecosystem services is a good point of departure. (3) In the built-up areas and intensively used agricultural sites, beyond the minimum standards for land use intensity, a technological service based approach will be necessary. A division of ecosystem management into these three zones confirms the complementarity of biodiversity and ecosystem services for policy and management strategies. The concept of this triple division can help to facilitate the discussion of a joint achievement of the goals for biodiversity and ecosystem services in the field.