Spatial optimization of ground based primary extraction routes using the BestWay decision support system

Improving productivity in forest logging operations while reducing negative impact on soil and water streams is increasingly gaining more attention. Positioning primary extraction routes is crucial in these efforts as it has a huge impact on efficient and sustainable forwarder passages. To minimize the total forwarding distance and avoid steep terrain and impact on soil and water, a decision support system including a detailed optimization model and solution method was developed. Main information consisted of a detailed digital terrain model, depth-to-water maps and forest volume density. The information was supplemented with the extent of the stand, position of the landing(s), nature and culture conservation sites, and any known unavoidable crossings in the terrain (e.g., streams). Fast solution time of the model was a critical requirement, hence a decomposition method based on Lagrangian relaxation was developed. The system was evaluated in two case studies in Sweden. In the first case, the optimization model performance was analysed at 30 final harvesting sites. In the second case, experienced forest company staff evaluated the primary extraction routes at 19 harvest sites in operational conditions. The results indicated faster planning, shorter driving distances and potential to reduce negative impact on soil and water.