Analysing the connectivity of the turquoise infrastructure: definition, characterization, and operational issues

Abstract

The fragmentation of the landscape is defined by a rupture of connection within ecological networks. The concept of green and blue infrastructure has emerged as a tool for the protection and restoration of ecological continuities in the territories. New ecological networks have recently been proposed to identify other effective ecological discontinuities. This is notably the case of the turquoise infrastructure associating the blue infrastructure and the part of the green infrastructure in functional interaction. It includes different types of aquatic and terrestrial habitats on which many species of amphibians, odonata and other invertebrates or chiropterans depend. The turquoise infrastructure is receiving increasing attention in the operational world, even though its definition and characterization methods are not yet stabilized. This article proposes to contribute to a better definition and understanding of the turquoise frame. Based on the landscape graph approach, which is now widely used to model ecological networks and measure their connectivity, the INTERFACE project has developed an innovative multi-habitat network protocol to consider habitat heterogeneity when assessing the connectivity of the turquoise infrastructure. It thus makes it possible to go beyond the delimitation of a buffer zone around watercourses and to identify functional zones to be preserved, vulnerable zones and points of conflict where it would be interesting to restore aquatic and/or terrestrial habitats to improve connectivity.