Modellbaserat beslutsstöd för stubbskörd [Model based decision support for stump harvest, in Swedish]

In this study a decision support model for tree stump harvest was developed. The model takes into account four criteria: economy, energy and climate, biodiversity, and land and water. The value of each individual tree stump was calculated separately for each criterion. The four criteria values were then weighed together into a final suitability score for stump harvest. The final suitability score decided whether the decision support model recommended harvest of each individual tree stump or not. Data from the harvester collected at final felling was used as input to the decision support model. For each stump the values used in the model was dry mass, stump diameter, tree species and position. In addition, the harvesters log track was used as a basis for localising the terrain roads within the stand. Other geographical data used was elevation data, presence of objects with special value for biodiversity and land/water, such as key biotopes, open water and moist soil. A special study was conducted to estimate the soil stability from a topographical wetness index.The decision support model was evaluated on an existing felling 2010 in Northern Uppland. The area was 45 hectares with about 26 000 stumps. The result of the decision support model showed that general economic parameters had the greatest impact in both sensitivity and scenario analysis. The most important variable was the price for stump biomass at road side. The decision support model results left continuous areas of the stand with all stumps unharvested. The reason for this was the economy criterion's sensitivity to the local amount of stump withdrawal per hectare. Low stump withdrawal gave high harvesting costs. In that economy was the only criterion which motivated stump harvest, the model never suggested harvesting a stump unless surrounding stumps were harvested too.There is potential for developing this decision support model further using updated knowledge and examining the impact of different criteri
QC 20170914