Effects of prospective landscape changes on species viability in Segre River valley, NE Spain

Abstract

Traditional land use in Mediterranean region resulted in complex landscape structures characterized by great ecological and cultural diversity. Recent changes such as intensification of agriculture, infrastructure development, rural depopulation and abandonment of the less productive regions led to landscape simplification and loss of biodiversity. In this project, we used a multispecies modelling approach to explore the possibility to develop landscape management plans that combine urbanization and infrastructure development with maintenance of traditional land-use to prevent further loss of biodiversity. For this purpose we studied the effect of progressing land use changes on the abundance and viability of fauna in the Spanish Pyrenees landscape. We compared the present land use situation in Cerdanya and Alt Urgell with foreseen changes in a near future grouped in two management scenarios. The assessment of the population size and viability of indicator species was conducted with the landscape model LARCH. Our results indicate that most of the selected species maintained viable populations in the present situation. Conservation of traditional land use would strongly improve the viability of the species characteristic for the habitats of higher conservation value like riparian forest. In contrast, the abandonment of traditional land use would lead to a decline of numbers and loss of viability of all species, with the strongest negative impact for specialist species. Based on these results we developed specific land use recommendations, both at local and regional level, that allow combining conservation efforts with economic and demographic developments in Mediterranean regions.