A GIS-based stand management system for estimating local energy wood supplies

A GIS-based system for decision support in wood procurement management was developed in order to identify energy wood harvesting alternatives during the integrated planning of harvesting operations. The system uses the information content of existing stand databases and an estimation method which is based on three major modules: i) modelling of energy wood volumes, ii) modelling of costs of haulage to the roadside and road transportation, and iii) economical allocation analysis of material flows. An application of this technology demonstrates how estimation of the total potential of residuals for local energy use can be integrated into wood procurement planning in Finland. Three experiments were prepared for testing this application. Based on the thinning regulations laid down by the Finnish national forest management organization Tapio, wood harvesting on permanent sample plots was simulated by two alternative procedures, one based on the empirical diameter distribution and the other on a theoretical Weibull distribution derived from the mean variables. The effects of these procedures on the extent of the residual energy wood potential were investigated. The third test compared this system with another system often used in Finland. The experimental results suggest that the theoretical distribution produces unreliable estimates in the case of untreated or young stands. Furthermore, the conventional system underestimates the potential of the residual energy wood. The implications of these results for improving the strategic planning of energy wood procurement in Finland are discussed.