Medium-Term Evolution of Forest Productivity in the French Mountains: The Use of National Forest Inventory Data

The assessment of changes in forest productivity at regional or national level is an important issue for wood industrialists, forest owners and managers as well as environmentalists. For example, when elaborating prospective studies about wood supply, the future evolution of forest productivity is one of the basic underlying hypotheses (Guero and Houllier 1990; Houllier 1992) but, because of the lack of reliable information, it is generally assumed that forest growth will remain unchanged. Furthermore variations in growing stock and in current increment are essential, but often neglected, elements of the global carbon budget and can be used for detecting forest decline (see Kauppi et al. 1992).