THE INFLUENCE OF STRUCTURAL DIFFERENTIATION OF TREES AND SELECTIVE LOGGING ON PHYSIOLOGICAL PROCESSES OF SCOTS PINE
L. V. Zarubina1, S. S. Makarov2,3, I. B. Kuznetsova4
1Federal State Budgetary Educational Institution of Higher Professional Education Vologda State Dairy Farming Academy by N.V.Vereshchagin, Vologda, Russian Federation
2Russian Timiryazev State Agrarian University, Moscow, Russian Federation
3Northern (Arctic) Federal University named after M. V. Lomonosov, Arkhangelsk, Russian Federation
4Kostroma State Agricultural Academy, Kostroma, Russian Federation
Keywords: Pinus sylvestris L, dominant, co-dominant and deppressed trees, drained lands, root respiration, photosynthesis, pigments, transpiration, shoot growth
Abstract
The results of studies of physiological processes (root respiration, intensity of photosynthesis and transpiration, pigment content, growth of needles and shoots) of Scots pine ( Pinus sylvestris L.) trees of different groups of subordination of a 230-year-old drained same-aged shift-sphagnum pine forest and the influence of selective (mine) felling. The position of the pine tree in the tree stand was consistent with the physiological state of the tree. The highest intensity of physiological and growth processes was noted in dominant trees (according to G. Kraft, trees of class II) - 1.5-2 times higher than in other groups of trees (co-dominant, oppressed). The lowest activity of physiological and growth processes was observed in oppressed trees. After selective felling, the illumination under the canopy of the tree stand increased by 3.2 times compared to the control without felling (up to 47.9 % of the illumination of the open area) and became favorable even for the growth of undergrowth. In pine trees left for cultivation, root respiration increased by 1.5 times, the intensity of photosynthesis and transpiration increased by 1.2-1.5 times, the content of chlorophylls decreased by 15-42 %, carotenoid pigments - by 5-32 % compared to control. The highest physiological and growth response to the selective cutting was shown by dominant trees of Kraft’s class II, and the lowest - by deppressed trees of class IVa. Mine cuttings did not change the structural differentiation of trees in the canopy, but increased their physiological activity, the growth of needles and shoots.
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