Detecting threatened biodiversity by urbanization at regional and local scales using an urban sprawl simulation approach: Application on the French Mediterranean region

Abstract

a b s t r a c tUrbanization is a major threat on biodiversity due to the direct destruction of natural and semi-natural habitats and to the indirect impacts caused by urban areas beyond their limits. In this study, we proposed a methodological framework to assess the potential impacts of current and future urbanization on high diversity sites and their associated species across the entire French Mediterranean region. Using a 100 m grid cell, we adapted a land-use change (LUC) model to project future urbanization over a 20 years period. We developed a multi-level approach based on three impacts of urban development: the direct consumption of high diversity sites, the indirect urban effects on the surrounding area over a scale of 2 km and a scale of 50 km. Our model predicts that 35% of the total number of sites can potentially be impacted by urbanization (i.e. at least 1 ha predicted to be built between 2006 and 2030). 3.2% of the total number of sites may lose 10% or more of their surface area to urbanization. We found that the impacts of urban area and urban growth differ among the three different pressure indicators in terms of surface area and localization of sites, number and nature of species impacted and variation of these patterns between the two dates. In general, most of the sites under pressure are located in the coastal part of the study region and are of smaller surface area than average.

The Environmental Impacts of Sprawl: Emergent Themes from the Past Decade of Planning Research

“…Sarvestani et al [27] use remotely sensed imagery and GIS to quantify and map the spatial dispersion of Shiraz, Iran from 1976 to 2005. Overall, the literature addressing land resource impacts from both developed and developing countries are comparable in their methodologies with remote sensing and GIS tending to play a prominent role [3,17,18,20,27,37,51,55,63].…”

Spatial mismatches between plant biodiversity facets and evolutionary legacy in the vicinity of a major Mediterranean city

“…The landscapes of these outcrops are characterised by a mosaic of low matorrals ("garrigues") mainly dominated by Quercus coccifera with open rocky spaces and a low vegetation cover formed by herbaceous plants. Along with an increase in the human population density occurring in Mediterranean lowlands near the coast, the naturally open habitats of Provence are affected by a combination of urban sprawl, habitat fragmentation, trampling and direct or indirect pollution (Barbero et al, 1990;Médail and Vidal, 1998;Tatoni et al, 2004;Dumas et al, 2008;Baumberger et al, 2012;Vimal et al, 2012). In parallel, the rocky habitats of Southern Provence shelter many rare or endemic plant taxa that make this area a priority for biodiversity conservation assessment and management.…”

“…A. provincialis occurs on limestone outcrops in Provence (south-eastern France) surrounding the big city of Marseille, and its habitats are threatened by severe urban sprawl, recreation and trampling leading to habitat degradation. Like many other endemic species of the Mediterranean region, A. provincialis is high in conservation priorities (Thompson et al, 2005;Hobohm and Tucker, 2014), but seriously threatened by human activities (Hoekstra et al, 2005;Underwood et al, 2009) and particularly by urban sprawl along Mediterranean coastlines in the vicinity of major cities (Médail and Diadema, 2006;Vimal et al, 2012).…”

Urbanization Forecasts, Effects on Land Use, Biodiversity, and Ecosystem Services

“…Calculations of carbon storage and agricultural production reveal that urbanization under the sprawl scenario will result in losses that are 3.5 times higher than urbanization under the densifi cation scenario. Vimal et al ( 2012 ) use a land change model to predict impacts of forecasted urban expansion across the French Mediterranean region. Over one third of the high-biodiversity sites in the region will potentially be directly impacted by urban expansion by 2030.…”