Evolution récente et future des paysages sylvo-pastoraux du Jura vaudois

Recent and future evolution of the silvopastoral landscape in the Jura vaudois Land-use management in silvopastoral landscapes is particularly complex because such ecosystems depend on a subtle equilibrium in the management scheme which aims to provide various ecological goods and services such as fodder, timber and biodiversity, as well as areas for leisure and attractive scenery. In this study we investigated land-use changes in the Parc naturel régional Jura vaudois, and the changes in tree cover density in two pastures using land-use statistics and aerial photographs. A prospective modelling approach was also undertaken on one pasture to assess changes in the landscape structure under two climate scenarios. A general tendency towards segregation between closed forests and open pastures was observed. The agriculture policy has markedly influenced the dynamics of tree cover density, but this effect depended very much on the local situation, for example, the proximity of a village, which allows a better optimization of farm management. The simulation of future development of these landscapes suggests that one might expect large changes in the structure and composition of the vegetation because of climate change. In the long run, areas of high tree densities will expand, and spruce will give way to beech and pine, depending on the warming intensity. Nevertheless, adaptation to new environmental conditions for sustaining ecological goods and services will call for management measures appropriate to the intensity of climate change. Furthermore, an active adaptive management based on experimentation and innovation, as well as allowing collaboration between scientists and land managers will be required to face and mitigate the ecological problems associated with climate change.