L’expansion séculaire des forêts françaises est dominée par l’accroissement du stock sur pied et ne sature pas dans le temps

Abstract

The expansion of French forests both in surface area and growing stock is explored based on National Forest Inventory data and Daubrée’s statistics (1908). The author studied their geographic variability under various ownership schemes (private, state or other regulated public forests) and depending on their composition (hardwood/softwood). Between 1908 and 2010, the increase in surface area was 5.1 million hectares (+ 50 %) with the fastest expansion rate in the Massif Central, and hardwoods gaining ground twice as fast as softwoods, although their overall proportions remained unchanged. Between 1975 and 2010, growing stock (+ 59 %, + 930 million cubic metres) developed three times more quickly than surface area but varied considerably between geographic locations: with area taking the lead in southern France and Brittany while in the Massif Central growing stock was preeminent, pointing to a certain continuity in relation to previous expansion of forest area. Over the same period, private forests and other regulated public forests experienced similar relative surface area variations (+ 20 %), but private forests accumulated twice as much growing stock (+ 80 %) as public forests. Between 1987 and 1994, private deciduous forests increased the most (+ 280 000 ha and + 105 million cubic metres), followed by private coniferous forests (+ 60 000 ha and + 63 million cubic metres). In the recent decade (2006-2015), increases in areas and stocks have continued at a pace of respectively 120 000 ha/year and 44 million cubic metres suggesting that this trend will continue over coming decades.