Наукові праці Лісівничої академії наук України (Oct 2018)
Growth and formation of oak stands with small-leaved linden participation under fresh hornbeam oak forest site type conditions in the Western Podillya
Abstract
In this paper we present the study of silvicultural and taxation indicators as well as the sanitary condition of oak stand of different ages with the participation of small-leaved linden, which grow under the conditions of fresh hornbeam in the Western Podillya. As a control we used clear and close to them in composition oak and linden stands. The study was conducted in middle-aged and mature stands. We have established that in the fresh hornbeam of the West Podillya complex oak stands are formed with the participation of common ash, common hornbeam, small-leaf linden, Scots elm, maple and sycamore maple and other tree species. The share of linden in their composition is from single trees to 6-8 units. Among them stands are dominated, in which the linden is 2-4 units. Common oak grows according to II and Іb bonitet and reaches maximum productivity (Ia and Ib bonitet) in stands, where the proportion of linden in their composition mostly varies within 2-8 units and lags behind in growth from oak in height by 10.0-46,1%. The worst growth of oak is characterized in stands, where the difference in height between oak and linden is not more than 7%. The growth of the oak is especially suppressed by the prevalence of its height by the linden. The correlation between the number of linden trees in the stand and the average height of the oak turned out to be converse and moderate (r = -0.49). The completeness and stock of tree stem wood vary greatly even within the age groups. In the medium-aged stands, the absolute completeness is 21.4-34.0 m2 / ha, and the timber stock is 172-374 m3 / ha. In mature trees, these figures, respectively, are 24.6-34.9 m2 / ha and 263-409 m3 / ha, and in mature - 26.6-40.3 m2 / ha and 330-487 m3 / ha. The largest stock of wood (409-487 m3 / ha) is formed by a stand, where the proportion of linden in their composition is 3-6 units. For experimental tree stands, the right-sided form of the distribution curve of trees in the tree stands in diameter is characterized by the predominance of moderate and high degree of sheath rate, and slight and moderate degrees of steepness. In 20% of experimental areas of water shoots oak trees were not detected. In other trees of varying completeness and productivity the number of oak trees with water shoots is 5.3-53.3%. It was established that the appearance of water shoots on oak trees grows in pure oak and close to them in the composition of tree stands. In complex tree stands, the appearance of water shoots on oak trees increases with a significant backlog of 22-50% of the height of the adjoining tree species from the height of the oak part of the forest tent. In trees there are trees of the 1st and 2nd categories of sanitary condition. Deadwood trees are found in 70% of experimental sites in the amount of 1.2-7.2%. The index of the sanitary state of the oak varies within 1.36-2.65. Worsening the sanitary state in middle age forests is associated with a significant density (1120-2507 per hectare) and with the processes of trees differentiation as a result of competitive interaction.
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