The top diameter limits in integrated forest fuel procurement system: Lithuanian case studies.

摘要

Economic possibility of undelimbed stems parts usage for forest fuel production is analysed in this article. The aim of the research is to assess the top diameter limits in integrated cut-to-length and forest fuel wood procurement system. The article provides mathematical model for calculation of spruce, pine and birch stems delimbing time. Delimbing costs of 1 m3 of wood, comprised from the same diameter stems parts, are presented in the article. In order to reach the goal, study of time expenditures of spruce, pine and birch stems delimbing was carried out and delimbing costs were calculated. Delimbing time of 725 spruces, 733 pines and 1000 birches was observed by cumulative timing method. The top diameter limits were estimated by maximum difference in net income of integrated and cut-to-length wood procurement. The top diameter limits depend on difference in prices of pulpwood and forest fuel. The top diameter limits were estimated for spruces, pines and birches in relation with diameter and development class of trees..