Dynamics of tree vegetation in deciduous forest after harvesting (middle taiga subzone, Republic of Komi)

We studied the dynamics of the number, composition and structure of stands, young growth and undergrowth in deciduous and deciduous-coniferous forest appeared after harvesting in the middle taiga for 10 years. It was established that during the study period the composition of the forest stand determined by the stock of wood in the birch-spruce young forest changed. In 2005 it consisted of 80 % birch, 20 % spruce and few pines and aspens, in 2015 it consisted of 70 % birch, 30 % spruce and few pines and aspens. For the same period the aspen-birch young forest composition changed from 50 % aspen, 40 % birch, 10 % spruce and few firs to 60 % aspen, 30 % birch, 10 % spruce and few firs. By the number of trees, in the studied stands deciduous species prevail (up to 92 %), with a large share of birch. In the young growth the birch dominates: the young growth of birch-spruce forest (20 years old) is composed of 80 % birch, 20 % spruce and few pines and aspens, that of the aspen-birch forest (48 years old) consist of 50 % spruce, 40 % birch, 10 % aspen and few firs. It was established that for the 10-year period the share of spruce in young growth increased. The ratio of the number of reliable young growth to its total number in the birch-spruce forest for spruce increased from 88 to 93 %, for birch, pine and fir did not change; in the aspen-birch stands - for aspen and fir young growth it decreased, for spruce it did not changed much, for birch it increased from 52 to 63 %. In the birch-spruce young growth the renewal of spruce under the canopy is more intense than in the aspen-birch forest. It was revealed that in the undergrowth represented mainly by willow and rowan there was a decrease in the number of woody plants by almost half, especially for willow. It was observed that the state and ratio of species of the undergrowth changed due to a significant drop in their growth as the trees of forest-forming species and competition between them. The assessment of the dynamics of forest stand and undergrowth of the studied plantations over a 10-year period showed that reforestation was quite satisfactory. The studies showed that the composition of the stand and young growth, as well as the nature of reforestation of the studied forest reflect the possibility of restoring the original spruce biocenosis in the long term.