Home – Home – Jornals – Siberian Journal of Forest Science 2022 number 6

In accordance with regulatory documents, the organization and conduct of logging operations should be carried out by methods and techniques that ensure maximum conservation of forest environment, contribute to the reproduction of valuable forests in the shortest possible time, and strentength their protective and protective functions. This is especially true for the coniferous-broad-leaved forests of the Far East, which are a unique formation that includes cedar and black-fir-broad-leaved, spruce-broad-leaved, hard and soft-leaved subformations. These forests are characterized by a very complex canopy structure. The composition includes, as a rule, 10-20 tree species, differing in their biology and growth, which creates a clearly expressed vertical density of the forest stand. The presence in plantations of endemic and forbidden species, as well as lianas and shrubs listed in the Red Book (2008) require a special approach to the methods and technologies of wood harvesting. Studies have shown that in the formation of coniferous-broad-leaved forests, selective felling methods and logging technologies should be predominantly used, allowing not only to preserve undergrowth and fine-grained valuable species, but also to ensure the formation of a post-cutting stands close to the original forest type. This leads to very important conclusions on the organization of wood harvesting only by certain types of machines and mechanisms using narrow stripe technology, which is confirmed by our research.

The total area of protective forests in Amur Oblast in 2022 was 2.51 million ha, of which 1.72 million ha (68.5 %) was forested, 0.18 million ha (7.2 %) was unforested land, and 0.61 million ha (24.3 %) was non-forest land. The share of protective forests in the forest fund of Amur Oblast is 5.6 % for forested lands and 8.2 % for all lands. For most of the post-Soviet period, the area of protective forests in Amur Oblast was characterized by a constant area: in the period 1998-2022, the total area of protective forests was in the range of 2.50-2.52 million ha. According to the contribution, the forbidden strips of forests located along water bodies are the most represented (47.9 % of the forested lands and 49.6 % of all protective forest lands). Spawning belts of forests are in second place in terms of representation (29.0 % of forested lands, 27.2 % of all lands). The third place in terms of contribution is occupied by protective forest belts located along public railways, federal public roads, public roads owned by the constituent entities of the Russian Federation (20.7 % of forested lands, 20.9 % of all lands). The prevailing categories of protective forests quite logically correspond to the economic specifics of the regions of Amur Oblast. The water protection services of the protective forests of Amur Oblast need to be strengthened. Under the conditions of climate warming, it is recommended that the regulatory recognition of forest services to prevent the degradation of permafrost is recommended.

For the first time a study of microbial communities of permafrost forest soils of the Yakut Botanical Garden of the Institute of Biological Problems of Cryolithozone, Russian Academy of Sciences, Siberian branch was conducted. The studied area is characterized by high soil diversity, almost all types of forest soils found in Central Yakutia are common here. It was found that in the studied permafrost soils in 2019, the number of cultivated microorganisms ranged from 5.2 ± 0.5 × 10² to 2.5 ± 0.1 × 10⁶ CFU/g of soil. Humus-carbonate soil turned out to be the most saturated with microorganisms of all types of permafrost soils, and malt was the poorest. According to the total number of microorganisms, humus-carbonate and pale gray soils formed as a result of the turf soil formation process were distinguished. It was noted that microorganisms were concentrated in the upper organogenic horizons and their number decreased with depth. Mycelial microorganisms dominated in the microbocenoses of the studied four out of five types of soils formed on loose light alluvial deposits, and ammonifying bacteria prevailed in the microbocenoses of malt developing on loess-like alluvial loams. It was found that the predominance of certain groups of microorganisms depended on the chemical composition of soils, as well as on the characteristics of their formation. Mycelial fungi were mainly represented by representatives of the genera Aspergillus sp . and Penicillium sp . Aerobic cellulolytic microorganisms were found in the amount of 5.2 ± 0.5 × 10² - 8.3 ± 4.1 × 10⁴ CFU/g, most of them were found in humus-carbonate soil. Nitrogen fixators were found only in humus-carbonate soil (98 %). It has been studied that the number of microorganisms with physicochemical parameters (C, N, pH, humidity) correlates in different types of soils in different ways. The change in the number of microorganisms mainly depended on the soil temperature, humus and nitrogen content.

The article notes the main sources of phytodetritus in undisturbed cryolithic larch forests of Central Evenkia. The features of the distribution of phytodetritus stocks and its individual components depending on the age of forest stands (young, mature and overmature) and forest types are considered. All these stands were formed on the territory of a small drainage basin in Central Evenkia after intensive ground fires in the early and last decades of the 20^th century. An uneven distribution of litter stocks was revealed both in age groups and forest types. Significant annual fluctuations in litter stocks over 7-year observation period were also noted. The composition of the litter is dominated by needles - 84.8-93.2% of the total mass, while the branches and bark of larch ( Larix Mill.) and birch ( Betula L.) leaves account for only 3.0-3.2, 4.5-2.6, and 7.7-< 1 %, respectively. It was established that according to the degree of accumulation of phytodetritus in the main types of larch forests of the basin under consideration, they are arranged in the following descending order: ledum green moss, red berry green moss, shrub green moss. Litter stocks in them vary from 2.4 to 76.3 t/ha. The total stock of litter in the territory of the basin is 133038 tons, of which 103916 tons fall on larch forests, with a predominance of mature and overmature - 4966 and 61188 tons, respectively. In larch forests of the permafrost zone, phytodetritus is formed mainly due to the litter of the moss-lichen cover. The role of litter from aboveground organs and root mortmass is insignificant. In all cases, with an increase in the age of forest stands, an increase in the mass of the litter is observed. The role of individual components of phytodetritus in the deposition of biogenic elements was revealed, with a significant predominance of carbon and nitrogen in them and an insignificant content of phosphorus and potassium as additional sources of mineral nutrition in forest biogeocenoses of the permafrost zone, and a low rate of their entry into the soil in the process of detritus mineralization was noted.

The species diversity and state of the ground cover of light coniferous forests in the territories of Irkutsk Oblast, polluted by emissions from three aluminum smelters (Bratsk (BrAZ), Irkutsk (IrkAZ) and Tayshet (TAZ)), differing in production technology and duration of impact on forests, were studied. 188 species of vascular plants from 49 families, 102 species of lichens, including 26 species of epigeal and 13 species of ground mosses were identified. Most species belong to the forest floral complex, mainly to the light coniferous zone-zonal group. Perennial herbaceous plants dominate in the biomorphological spectrum: its basis consist of long-rooted (30 % of the total flora), short-(26 %), and rod-rooted (13 %) species. The mesophytic species dominate in ecological spectrum. The most significant transformation of the species composition was observed in forest communities located in the industrial zone (within a radius of 0.5 km) of BrAZ, where the critical level of contamination of Scotch pine ( Pinus sylvestris L.) trees was found, the drying of trees and the degradation of the grass-shrub layer contributed to the formation of solid moss cushion from silvergreen bryum moss ( Bryum argenteum Hedw.) on the soil. In the industrial zone of TAZ and IrkAZ, where average and strong level of tree-stands contamination, respectively, was found we observed the increase of plant projective coverage to 70-85 % and the total number of vascular plant species due to the appearance of meadow, forest-steppe and ruderal, the composition of phytocenoses often changes towards the predominance of photophilic species. With a low level of contamination of tree-stands, changes in the floral complex are less pronounced and statistically insignificant compared to background territories.

Under conditions of a changing climate, the relevance of assessing the full carbon pool of all components of forest ecosystems increases, not only of the living aboveground and underground parts, but also of litter, large detritus, soils, etc. There are numerous estimates of the phytomass of the aboveground part of forest trees and stands, both taking into account the mass of branches that have died and preserved on tree stems, and without taking them into account. There is no information about the mass of dead branches on tree stems in the available databases on the phytomass of trees. Thus, the mass of dead branches of trees and stands is not included in the calculation of both the input and output components of the carbon cycle, and when estimating the carbon pool of forest ecosystems, it is underestimated by some unknown amount. In the published data on the phytomass of trees, the relative mass of dead branches, i.e. the ratio of the mass of dead branches to the aboveground phytomass, varies from 0.1 to 26 %, however, attempts to identify factors explaining such a wide range of it are quite rare. In this study, the first attempt was made to develop allometric models designed to estimate the mass of dead branches of growing trees of Scots pine ( Pinus sylvestris L.) and silver birch ( Betula pendula Roth) in the conditions of the steppe zone. The study was based on 465 model trees obtained on 35 sample plots. It was found that in the mature birch stand, the mass of dead branches is 1.32 t/ha and relative mass of dead branches is 2.5 %, in natural pine forests 0.9-17 t/ha and 0.7-13 %, respectively, and in plantations 0.2-13 t/ha and 1.3-11 %, respectively. The dependencies constructed for the relative mass of dead branches are combined with yield tables of the aboveground phytomass of stands of natural origin and plantations of the Turgay Depression. It was found that, depending on the origin of the stand, its age and site index, the relative mass of dead branches varies from 0.8 to 15 %. The proposed allometric models and inventory tables can be used in the assessment of the mass of dead branches on tree stems of pine stands. When calculating carbon pools in the forests of the steppe zone, it is necessary to take into account the mass of dead branches by applying increasing coefficients in pine forests from 0.8 to 15% and in mature birch forests 2.5 %.

The article presents for the first time data on the composition and structure of algae groupings in gray forest soils of the town of Usolʼe-Sibirskoe and its surrounding territories, exposed to technogenic pollution. Samples from 19 locations, mainly forest stands, located on the territory of the town (12 locations) and its surroundings (7 locations) were studied. Using culture-dependent methods, 77 species from five divisions of Cyanoprokaryota (22 % of the total number of species), Bacillariophyta (5 %), Ochrophyta (9 %), green algae (Chlorophyta) (61 %), Charophyta (3 %) were registered. The largest number of species are represented by green algae, which is typical for forest soils. A variety of Cyanoprokaryota species was noted in the soils of the town, which are characterized by lower acidity, increased content of exchangeable calcium, sodium, sulfur, and a lower content of total nitrogen compared to the background. In the studied forest stands on the territory of the town, the diversity of algae groupings was higher (the average number of species was 11.7) than in its surroundings (an average of 9.9 species). Composition and structure of algogroups of the studied forest soils of Usolʼe-Sibirskoe testifies to their preservation of common features characteristic of such soils of natural biogeocenoses. According to the number of species, the distribution of species in the departments, the soil algocomplex of forest stands in the town of Usolʼe-Sibirskoe and its surrounding territories is similar to those of other industrial centers of Irkutsk Oblast: Sayansk, Shelekhov, and Irkutsk.

The methodology for valuating regeneration and compensation cost and calculating the amount of damage in case of logging, damage, destruction of green stands, developed for agricultural and municipal lands in the territory of Beysky district of the Republic of Khakassia, is discussed. The replacement cost of green stands is determined per one tree / one bush and is determined by the formula S_v = C_sp × Kd_1.3. The transition from replacement cost to compensation cost is due to the need to take into account in the price of each tree or shrub being valued various aspects of their value. The compensation cost is calculated by applying correction factors to the replacement cost, such factors as their location, actual condition, environmental and social significance, and is determined by the formula S_kd = S_v × K_t × K_s × K_sez× N_d, where S_kd. In cases where green spaces simultaneously belong to different categories allocated to take into account their social and environmental significance, the maximum value of a similar coefficient is taken into account in cost calculations. The amount of damage caused by illegal logging and (or) destruction of green spaces is calculated at the amount of the compensation cost using the multiplying coefficient K_п = 5. cost of damaged green stand. Payment of the compensation cost of cut down green stands in case of forced demolition and damage in case of illegal logging, damage, destruction of green stands shall be credited to the budget of the municipal formation of Beysky district of the Republic of Khakassia.

The article for the first time deals with the issues of natural regeneration of the forest in blown sands - a kind of deserts of the northern taiga and forest-tundra of Western Siberia, which arose on the site of automorphic pine stands, destroyed by natural and technogenic impacts. During the reconnaissance survey of several blows, it was found, that the main factor hindering the natural regeneration of forests in these peculiar deserts of the North is the wind. In this regard, forest formation on them is carried out only in areas adjacent to the leeward side of the forest walls and in low places, as well as in voids between large-sized logging residues covered with sand.