Распределение влаги по сечению ствола дерева в ельниках черничных

Abstract

The article considers the change in the moisture content in the wood along the cross-section of spruce trunks, it also analyzes the influence of the trees age and the diameter of the trunk on the wood moisture content. The research was carried out in the Arkhangelsk Forestry in the bilberry spruce forests of different age classes (from IV to VIII). 10 trial plots were laid in clear stands or with a small mixture of birch and pine. To study the moisture content of spruce trunks, 15 sample trees (150 in total) were selected for each trial plot. The wood moisture content was determined on cores sequentially divided into 5-millimeter segments. Wood samples were weighed on a VT-500 torsion balance and dried in a drying cabinet at a temperature of 105 °C to a completely dry state. The relative moisture of wood was calculated. As a result of the conducted studies, the moisture of sapwood (from 44,8 to 45,9 %) and heartwood (from 32,2 to 36,1 %) was established. Two models of changes in the amount of water at different distances from the cambium were identified. The majority of trees (78–98 %) are characterized by a well-defined water supply zone, the moisture content of which is maximum at a distance of up to 25 mm from the cambium, after which it decreases sharply. The water supply zone is represented by approximately 40...50 outer annual rings. The second model is characterized by a gradual decrease in wood moisture along the radius from the periphery to the center of the trunk. Such a model of changes in the moisture content of wood in the cross-section of the trunk is rare, mainly in young trees. As the trunk diameter increases, the moisture content of sapwood decreases. There was no significant difference in the sapwood moisture of spruce trunks of different age classes. The sapwood moisture decreases from the root neck to 1.5 m in height of the trunk, varying from 52...53 % to 49,0...49,5 %.