Investigating the balance between timber harvest and productivity of global coniferous forests under global change

A widely used assumption in forestry is that the demand for timber will exc eed the maximum level available from forests on a sustainable basis. In thi s study, measurements of extracted timber and modeled forest productivity w ere used to investigate the relationship between harvested timber and natur al forest productivity for current conditions, and under global change scen ario. The analysis was confined to coniferous forests and countries that ha ve coniferous forests within their territories. Annual roundwood production from the database of Food and Agriculture Organization was used as an appr oximation of annual timber harvest for each country. Annual stem primary pr oductivity of coniferous forests was estimated using the BIOME-BGC model. B ased on the current rates, annual timber extraction was extrapolated for ea ch country for the next 80 years. Then, on a country basis, the timber harv est was related to the modeled forest stem productivity, assuming that the area of coniferous forest would stay unchanged for the next 80 years. The r esults of this study suggest that global coniferous forests currently produ ce more wood than people consume, but that this gap will narrow in the futu re. The results also suggest that wood extraction may reach forest regrowth by the middle of the next century, even though most coniferous forests are loc ated in high latitudes and may have an accelerated stem growth associated w ith the joint effect of climate change and elevated carbon dioxide concentr ation in the atmosphere.