Economic aspects of silvicultural treatments in oak stands

The aim of the study was to economically analyse the costs of silvicultural management treatments in oak stands. The basic research material was obtained from selected forest districts belonging to the Regional Directorate of State Forests in Poznan. The economic analysis concerned only stands in which the share of oak in the species composition of the stand was above 60%. In total, data from 1,644 silvicultural activities performed from 2015-2019 were used for the study. The study analysed five types of tending interventions (groups of activities) that occurred in all of the studied forest districts. In order to demonstrate significant differences in unit cost average values related to the group of activities, the analysis of variance test in a single classification was used. In addition, cluster analysis was used for a more complete interpretation of the data and grouping of the examined elements. After carrying out a significance test, it could be concluded that the group of activities had a significant impact on the unit cost of the activities performed (p<0.000). Cluster analysis made it possible to look for similarities in the overall multi-activity structure of unit costs assigned to individual habitats. The analysis showed how similar individual habitats are to each other in the entire structure of costs incurred for five unique groups of activities. A dissimilarity matrix between the studied factors (group of activities and forest habitat types) and its visualization via a heat map were used in this study. Sorting the map by differences in the dissimilarity matrix allowed us to detect relationships in the cost data. The data mining analysis presented in this paper enabled the identification of factors influencing the level, structure and variability of the costs of tending oak stands.