Home – Home – Jornals – Siberian Journal of Forest Science 2020 number 3

Two geoinformation databases have been created, which provide information on the parameters of pine forests in the large Baikal region. The database «Elemental chemical composition of pine needles Pinus sylvestris L. in the Prebaikalia» contains the data obtained by the authors on the quantitative content of 39 elements and 20 organic pollutants in pine needles at 162 sample plots (SP), located in the southern part of the Irkutsk region territory, where a large industrial zone is located, aerial emissions of which are one of the main causes of forest pollution in the region. Information on changes in the elemental composition of needles in dynamics from 1992 to 2018 is given. The data are presented: 107 types of pine stands, 50 types of soils, 59 chemical elements and organic pollutants. In the second database «Ecological and physiological state of pine forests in the catchment basin of Lake Baikal», located mainly in the territory of Buryatia. Geographic coordinates, landscape location, type of forest, type of soil, parameters of the vital status of tree-stands, natural and anthropogenic factors that negatively affect the state of forests are indicated for each SP. The created databases contain a large enough amount of information to automate the collection of data on the forests state, analyze data, and form an information basis for GIS. This is of both scientific and practical interest in the planning of work on rational forest management.

On the example of the Azas State Natural Reserve, the potential productivity of forest stands is considered depending on the indicators of forest growth conditions. Multiple regression equations are formed. The class of productivity (bonitet) is used as a function. Initial information for drawing up the equations - materials of forest planning and data of digital elevation model. Soil, moisture and heat are the main factors affecting the development of the stands. The heat supply of locations is considered as a derivative of relief parameters. Soil moisture and fertility indicators of locations are constructed based on the characteristics of forest inventory indicators. The Siberian larch and the Siberian stone pine forests are found throughout almost the entire high-altitude profile of forests in the reserve: the range of absolute heights of larch about 1600 m, the Siberian stone pine - 2200 m, Scotch pine - 700 m, the Siberian spruce - 500 m. It turns out that the vertical temperature gradient significantly affects the representation of tree species in the high-altitude zones of the reserve, but practically does not affect the productivity of the stands. A significant decrease in the class of bonitet as the climb is observed only in larch stands. The effect of slope on productivity is not observed. The ranked number of soil moisture is demonstrated relative to the generalized qualitative indicator of forest-growing conditions of the forest type. There is a statistically significant relationship between the index of forest growth conditions and soil types. It is revealed that the class of bonitet of Scotch pine stands is determined mainly by soil moisture; in larch stands there is a dependence of the class of bonitet on the absolute height of the terrain, humidity and soil fertility; the productivity of the Siberian stone pine and the Siberian spruce stands naturally depends on soil moisture and fertility. Mapping of the potential productivity of stands is made by the values of the absolute height, soil moisture, and soil fertility of forest inventory compartments. Visual analysis of the map shows: on the best mode of moisture and soil fertility, located on the heated areas, can potentially grow more productive stands; it is established that within the reserve the most favorable forest conditions have developed on the terraces of the Azas river, meadows, forest-steppe areas; as elevation increases, forest conditions deteriorate.

At present the problem of abandoned agricultural land overgrown with trees and shrubs is relevant in Russia. At the same time, there is a problem of fire hazard of coniferous young forest, formed on these lands. The paper considers the fire hazard of pine young forest on unused agricultural lands with different duration of the period of termination of land cultivation. On the basis of spatial distribution of young pine trees on overgrown fields it is revealed that overgrowth occurs gradually and it begins from the bordering forest. The main amount of self-seeding and undergrowth occurs at a distance of up to 125 m from the bordering forest in the amount of 4 to 7 thousand trees per ha, and as you move away from the bordering forest, the number of trees gradually decreases. On the studied fields different-aged pine young growth is formed, the vital condition of which is estimated as satisfactory. Proportion of healthy self-seeding and undergrowth is more than 70 %, unreliable to 20 % and dry up to 10 %. The number of seedlings in the fields is insignificant, there are no tree shoots in the fields, which is due to the overgrowth of the fields with grassy vegetation from 53 to 80 % of their area. Duff on sites for this period is not formed. The stock of ground fuels consisting of litter and moss does not exceed 180 g/m² and does not form a continuous layer, in connection with which the spread of fire is impossible. It is revealed, that the ignition is possible in places where young growth grows in small groups or singly in the presence of a loose layer of dry grass consisting of cereals. Young pine stands are most flammable in spring.

The dynamics of ecological and microbiological parameters of the soils in fruticulose-lichen-green moss type of pine forests after fires of different intensity and logging tree stands at the initial stage (up to 10 years) of vegetation restoration in the Lower Priangar’e region are discussed in the article. It is revealed that at four to five year period after fires content of microbial biomass decreases by 2-9 times, total C_mic storages decreases by 20-40 % in the upper organo-mineral horizon of illuvial-ferrous sandy podzol, and the transformation of the structure and the number of ecological-trophic groups of microorganisms (ETGM), with more marked changes after high-intensity fires. The highest values of qCO₂ (6.7-27.4 µgС-СО₂/(mgС_mic · h)) were observed within four years after fires with a tendency to decrease its values. The maximum changes of the functional parameters of microbial communities, decreases the number of ETGM and changes its structure, increased microbial production of CO₂ by 54-40 % while reducing total C_mic storages by 20-40 %, and a high qCO₂ value (5.5-14 4 µgС-СО₂/(mgС_mic · h)) were observed in the soil in two-five years of deforestation with significant mechanical disturbance of litter, whereas in the soil of ten logging at the young stage the considered parameters of microbial communities approximated the control. The restored successions of microbiocenoses of the of illuvial-ferrous sandy podzol of pine forests in five to eight years after high-intensity fires and after logging of pine forests with disturbance of soil and vegetation cover had similar trend and focus, reflecting the transformation of hydrothermal and trophic soil conditions.

The structure of the Siberian stone pine Pinus sibirica Du Tour stands was studied using the example of late-successional chern Siberian stone pine forests with sedge, tall herbaceous and large forest ferns and mountain-taiga Siberian pine forests with bilberry and green hypnum mosses that are widespread in the North-Altai-Sayan and the East-Sayan (respectively) mountain forest vegetation province of the Altai-Sayan mountain ecoregion. A comparative structure analysis of stands by age, diameter and height was carried out in two significantly different climatic zone conditions. The Siberian stone pine stand in the chern sedge, tall herbaceous, large forest ferns Siberian stone pine forest has a wider age range (from 60 to 560 years) and a cycle type of long-term dynamics. The age composition of the Siberian stone pine stand in the mountain-taiga blueberry, green hypnum moss Siberian stone pine forest has a smaller amplitude (from 60 to 220 years) and belongs to an absolutely uneven-aged structure type. Despite the differences in the age composition of stands, the long-term development of both late-successional Siberian stone pine forests led to the formation of similar unimodal distributions of the data of stands structure by diameter and height, which, apparently, provide the most effective interaction of the keystone species with the environment. The dynamic stability of chern sedge, tall herbaceous, large forest ferns Siberian stone pine forest under conditions of abundant rainfall, high soil fertility and powerful development of lower layers vegetation is provided by the increased spatial heterogeneity of phytocenosis, a complicated interaction between the Siberian stone pine and the Siberian fir Abies sibirica Ledeb. populations and high lifespan of the Siberian stone pine trees. The resistance of mountain-taiga blueberry, green hypnum moss Siberian stone pine forests structural-functional organization in less favorable climatic zones conditions is formed by mass, almost permanent natural regeneration of the Siberian stone pine and stable tree recruitment in separate gaps. Thus, fundamental differences in the structure and dynamics of the Siberian stone pine coenopopulations in hyperhumid and humid climatic facies of the Altai-Sayan ecoregion are shown on the example of two representative objects. The results of the study can help predict main possible trends in the forest ecosystems transformation in different scenarios of natural and anthropogenic changes.

Ecotopic analysis of the Scots pine Pinus sylvestris L. population structure based on the ratio of intraspecific forms - red male cones P. s. f. erythranthera Sanio and yellow male cones P. s. f. sulfuranthera Kozubow was performed in the plantations in the Shira steppe of the Republic of Khakassia. It was found that the part of red male cones form trees is (22.5 ± 1.9) %, while in extreme growth conditions associated with a distinct lack of moisture or, in contrast, seasonal excess moisture, the share of their participation increases. A statistically significant relationship between the color of male generative structures and the stand DBH in various ecotopic conditions was identified by the information analysis. The trees’ yellow male cones form has larger stem diameters in the optimal and seasonal excess moisture content. The trees’ red male cones form has best radial growth in the most xerophytic conditions; a high abundance in seasonal excess moisture conditions and in high-density plantations, also characterizes them. The results obtained show that the less common red male cones form of the Scots pine is an adaptively significant «element» of intraspecific diversity, providing a functional «safety margin» of populations and their stability in extreme growing conditions.

In the European North of Russia, the need for scientifically based normative and reference materials for stands’ survey, including nonprincipal tree species, such as treelike willow, represented in the region mainly by sallow Salix carpea L., northern willow Salix borealis Fries, almond-leaved willow Salix triandra L., and their hybrids, was and remains relevant. Without maintaining a unified system of forest survey standards, it is impossible to conduct intensive forestry. Forest survey standards for a treelike willow were developed, taking into account the specifics of forest growing conditions of forest areas. The absence of forest survey standards for a treelike willow makes it difficult to improve the accuracy of accounting forest resources in the European North of Russia, to fulfill functions of protecting, safeguarding and restoring forest resources, and to increase the ecological functions of forests. The article presents new tables of volumes of willow tree stems in diameter and height in the north-taiga region. When developing the tables, the data of 42 sample plots were used, which were established in the Verkhnetoemsky and Arkhangelsk forestry districts of Arkhangelsk Oblast, on which 105 sample trees were measured. Tables of stem volumes by diameter and height of a treelike willow are used to determine the stock of stand, as well as to determine the volume of individual tree stems in the sample plots during the studies. The shape of willow stems were studied using sample trees using the old form factor. The height range with the appropriate diameter was taken from the sample plot data and the measured sample trees. Forest survey standards for a treelike willow in the north-taiga region of the European part of the Russian Federation previously have not been developed.