Long-term Coordination of Timber Production and Consumption Using a Dynamic Material and Energy Flow Analysis

A dynamic model for wood and energy flows is used to analyze regional timber management. The model combines a site-quality-dependent forest-growth module with modules for the timber industry, timber products use, waste management, and energy supply. The model is calibrated with data of a Swiss lowland region for the period of 1900-1997. Scenarios are developed for the period until 2100 in order to discuss possible future roles of domestic timber. Model simulations show that, with present strategies, timber overproduction will further increase in the twenty-first century because of an increase in forest site quality in the second half of the twentieth century, among other reasons. The increase in building gross floor area of the region by a factor of 5 during the twentieth century coincides with a reduction of timber use in building construction by a factor of 4.5, from 90 kg/m(2) to 20 kg/m(2). Increasing timber density in buildings could address overproduction; however, a strategy of timber construction could not be accomplished with domestic timber alone. A balance of production and consumption on the present level could also be achieved in a scenario in which the present building stock is gradually exchanged during the twenty-first century with buildings that exclusively use a combination of solar panels on roofs and domestic firewood and used wood as heat-energy sources. These replacement buildings would have density typical of late twentieth-century buildings, and they would need to perform on a low-energy standard of not more than 130 MJ/m(2)/yr.