Format: ORAL

Sandra Navas1, Rut Snchez de Dios1, Felipe Domnguez Lozano1

1 Department of biodiversity, ecology and evolution, Complutense University of Madrid, Madrid, Spain.

Land-use change analysis is widely accepted as a biodiversity conservation tool. However, it has seldom been used in the context of endangered plants. Our aim is to accurately quantify changes in land cover over the last 60 years in a selection of 58 populations of 43 Spanish threatened plants. Consequently, we explain how these changes correlate with major trends in biodiversity conservation such as human demography, ecological gradients or the spatial distribution of plant threats. A semi-automatic classification methodology has been used to identify land-cover changes by comparing aerial photographs from 1956 to 2019 in an established radius around field plots. Secondly, information from field plots and external databases was analyzed using GIS layers and PCA statistics. Land-use changes have been extensive throughout the sampled threatened plant populations. On the one hand, we find species inhabiting mountain areas, which are less prone to land-use changes because human activities are limited. On the other hand, species that have their habitats in coastal and/or urbanized areas. Hence, land-use changes define two groups in the endangered flora: a first groupis related to high human densities, low elevation settings and low in situ protection, while a second group is related to the cessation in human pressure, protected area establishment and increase in forest cover. Based on our research, it can be concluded that passive rewilding is not the solution to conservation problems for plants, and could be counterproductive.Urban land-use changes present a more urgent issue, especially for those endangered plants in coastal areas. Finally, high herbivore density and richness compromise endangered plant populations growing at high elevation in protected areas.