Within the scope of the Alter-Net WP I3, CEMAGREF has set-up in collaboration with several other institutes (CNRS, University Joseph Fournier of Grenoble, University of Savoy) and regional bodies (e.g. National Park of Ecrins, Natural Regional Park of Vercors, National Botanical Conservatory, National Forest Office) the LTSER plat-form French Alps. This LTSER site federates about 50 scientists in the field of climatology, ecology, social science, and economy. Main concerns of the our LTSER site are to strengthen a scientific network on the thematic of land use and climate changes in the French part of Alps, to conduct long term observations and experiments and to develop strong links with land managers/users. The LTSER plat-form French Alps is in particular working on climate change and impacts on ecosystems, land-use change dynamics, and biodiversity and ecosystem functioning.