Improving the integration of ecological functionalities in the mitigation hierarchy

Abstract

The mitigation hierarchy does not give enough importance to the impacts of development projects on habitat connectivity. However, environmental policies and the objective of no net loss of biodiversity underline the importance of preserving ecological networks to limit the habitat fragmentation. The failure to fully understand spatial dynamics and understanding of ecological functionalities cause these shortcomings at all stages of project design. We propose here a methodological framework encompassing all these steps: from the assessment of conservation issues, by quantifying the overall impact of a development project on the habitat connectivity, to the dimensioning of ecological measures, by defining their optimal location to maximize their gains. To this end we combine a species distribution model with a landscape functional connectivity model. The case study of the new football stadium in the metropolis of Lyon has highlighted the importance of this integrated approach to decision-making processes in land use planning. This method is a valuable contribution to support both policy makers and project developers applying the mitigation hierarchy to protect biodiversity, as well as for environmental authorities.