A data-driven approach to multi-facet prioritization of biodiversity in regional conservation planning

Strategic Environmental Assessment (SEA) of land-use planning is a major tool to minimize the environmental impact of urbanization. SEA implementation is, however, often based on incomplete biodiversity diagnostics and almost entirely focused on lists of priority species with high conservation value. At the same time, recent studies in Systematic Conservation Planning illustrate how to integrate the multidimensionality of biodiversity on a large scale, such as ecosystem function and species' evolutionary uniqueness, which could broaden the spectrum of stakes for SEA on a regional scale. The objective of this study is to assess the complementarity and feasibility of adopting a multi-facet approach to define spatial biodiversity priorities and inform regional SEA stakeholders. To do so, we used a spatial prioritization tool based on Species Distribution Models (SDM) to assess four facets of biodiversity (“priority species list”, “threatened species”, “functional distinctiveness” and “phylogenetic distinctiveness”). In a study of three taxonomic groups (Aves, Flora, and Papilionidae) in three regional administrative entities in France, our results confirm the pertinence of different facets of biodiversity to identify new and complementary priority areas for conservation. However, the limited amount of data adequate for SDM may bias the choice of conservation priorities. We conclude on the clear need to promote a holistic approach to biodiversity conservation if we are to correctly reduce the impacts of development projects on a land-use planning scale.