Home – Home – Jornals – Siberian Journal of Forest Science 2024 number 3

The capsule review of the scientific editor for the thematic issue of the Siberian Journal of Forest Science, 2024, number 3 is presented, dedicated to stationary forest studies.

Although there are no official and permanent criteria for determining the position of your name in the list of authors of an article, the principle of “authors at the both sides of the list” is increasingly used in biomedical publications. The best addition to it is a detailed indication of the contribution of each author to the creation of the article.

In the indigenous southern taiga fern-forb fir forests on the Tom-Yaya interfluve (Tomsk Oblast), the characteristics of tree stands, underbrush, undergrowth, coarse woody debris, ground cover, soils and their contribution to carbon sequestration were studied. The average stock of the forest stand for the type of biogeocenosis was 315.8 ± 56.1 m³/ha, the average stock of the Siberian fir ( Abies sibirica Ledeb.) in different stands varied from 99.2 to 201.4 m³/ha. In terms of forest health condition, the forest stands are weakened to varying degrees, the fir elements of the forest stands are stronger, which is largely due to their damage by the invasive four-eyed fir bark beetle ( Polygraphus proximus Blandford). The underbrush is sparse or of medium density (880-2720 pieces/ha), formed mainly by red raspberry ( Rubus idaeus L.) and rowan ( Sorbus sibirica Hedl.). Undergrowth with an absolute predominance of fir, its number (800-920 trees/ha) characterizes unsatisfactory regeneration in all studied stands. The average volume of deadfall for the type of biogeocenosis was 2.1 ± 0.5 m³/ha, stumps 3.3 ± 0.8 m³/ha, brushwood - 9.2 ± 5.3 m³/ha. The features of the phytocenosis include high values of floristic diversity (131 species), species richness of the grass cover (105 species) and species richness of plant communities (57 species per 400 m²). The increased participation of ferns in the composition of the grass stand is due to the presence of windows occupying from 5 to 30 % of the area of the phytocenosis, formed in stands at the site of fallouts and dead trees, mainly due to the drying out of fir damaged by the four-eyed fir bark beetle.. For the first time, data have been obtained on the phytomass of the ground cover of southern taiga fir forests in Western Siberia, estimated on average at 0.88 t/ha, with a wide variation of this indicator due to the peculiarities of the horizontal structure of the ground cover and different illumination in sub-canopy parcels and windows. The features of the composition, structure and thermal regime of the soils of the studied biogeocenoses are shown. Data are presented on changes in the productivity of phytocenoses, soil humus and carbon reserves in various components of the studied forests.

The Tellerman experimental forestry of the Institute of Forest Science, Russian Academy of Sciences, located in the southeast of Voronezh Oblast, has a long history. It was established on the initiative of Academician V. N. Sukachev in 1944 as a place to conduct complex long-term studies in broad-leaved forests on the border between forest-steppe and steppe. For almost 80 years specialists of different profiles worked in the territory of the forest area: foresters, geobotanists, soil scientists, zoologists, microbiologists, entomologists, phytopathologists. Extensive studies was carried out on the hydrology of the massif and water regime of stands, the environment-forming role of the forest, phytomass reserves were determined, productivity of stands in different forest types was determined, and a cycle of silvicultural experiments was established. The comprehensive study of biogeocenoses also included root systems, phenological, geobotanical, zoological, entomological, microbiological and mycological studies. The scientific basis for the establishment of pedunculate oak ( Quercus robur L.) crops in the forest-steppe was developed, taking into account its form diversity and the results of silvicultural experiments laid down in the first decades of the forest region’s existence. The study of silvicultural aspects of oak stands degradation allowed us to develop practical methods of reproduction of oak forests on clear cuts of stands mixed with oak by sowing acorns with a shortened period of thinning.

The observed increase in temperature, caused by increasing concentrations of climate-active (greenhouse) gases in the atmosphere, primarily carbon dioxide (CO₂) and methane (CH₄), may be responsible for the projected release of carbon accumulated over millennia in large areas of northern latitudes. The scale and duration of the expected effect remains an open question, due to the sporadic nature of quantitative estimates of carbon flows. The work reflects the current status, directions and main results of long-term instrumental studies of carbon flows in the ecosystems of the middle taiga subzone of Central Siberia, on the basis of the Middle Yenisei experimental station of V. N. Sukachev Institute of Forest, Siberian Branch of the Russian Academy of Sciences (ZOTTO observatory). The dynamics of CO₂ and CH₄ concentrations in the atmosphere from 2009 to 2020 are presented. The values of net ecosystem exchange of CO₂ for forest-swamp complexes are given, indicating that they act as a sink (sink) of atmospheric CO₂. For representative ecosystems, an assessment of soil CO₂ emission fluxes and the seasonal variation in the values of photosynthetic carbon assimilation by dominants of the subordinate vegetation layer are presented. The patterns of behavior of dissolved forms of carbon in the waters of streams draining oligotrophic and eutrophic swamps in the study area were revealed, and the values of CO₂ emission from the water surface were presented.

The phenology, productivity, intensity of gas exchange and resistance to biotic factors in climatic ecotypes of Siberian stone pine ( Рinus sibirica Du Tour) from latitudinal (from the West Siberian forest tundra to the low mountains of the Western Sayan) and longitude (from the Urals to the Northern Baikal region) profiles were studied in the 30-year clone archive at the scientific field station «Kedr» of the Institute for Monitoring of Climatic and Ecological Systems, Siberian Branch of the Russian Academy of Sciences. It has been established that Siberian stone pine is characterized by a high level of hereditarily determined ecological and geographical differentiation in productivity and resistance to biotic factors (pests and fungi diseases) when growing vegetative progeny in the south of the forest zone. The main factor of differences between ecotypes is the heat supply of the growing season in their places of origin. It increases significantly more from north to south than from east to west. Therefore, the differences between latitudinal ecotypes are much greater than between longitudinal ecotypes. The intensity of respiration depends more than the intensity of photosynthesis on the climate in which a given population was formed. Ecotypes from cold habitats have significantly higher respiration costs. This is an important factor in reducing their productivity in warmer climates. Being weakened by the imbalance between photosynthesis and respiration, they are damaged by pests and diseases which becomes an important factor in further reducing productivity. In conditions of global warming, ecotypes from warmer climates are not inferior to the local ecotype in terms of resistance to biotic factors and surpass it in productivity. Therefore, they are recommended to be actively used for breeding.

Quantitative assessments of the carbon balance of terrestrial landscapes and, specifically the permafrost zone, where the most significant warming trends are observed, require taking into account the export of terrigenous carbon beyond their boundaries with lateral flow. The paper presents the results of long-term monitoring of intraseasonal and interannual fluctuations in the concentrations of dissolved organic (DOC) and inorganic (DIC) carbon in the hydrographic network of the Central Siberian Plateau, carried out on the basis of the Evenkian field station of the V. N. Sukachev Institute of Forest, Siberian Branch, Russian Academy of Sciences (Tura settlement). Research is being carried out on more than 100 streams and rivers of various orders in the middle reaches of the Lower Tunguska River (62-66°N, 96-102°E) based on regular measurements of the concentrations of all forms of carbon, as well as quasi-continuous monitoring of the physical and chemical parameters using specific sensors and automatic loggers. It has been shown that the main limiting factors of lateral carbon flux within the Central Siberian Plateau at present are: 1) stocks of potentially mobilizeable organic carbon in terrestrial landscapes and 2) amount of precipitation in a sharply continental climate. An increase in the DOC flux is predicted both as a result of thawing of C-rich frozen deposits and an increase in the productivity of plant cover, and inorganic carbon - as a result of increased rates of silicate rock weathering and sequestration of atmospheric CO₂. Negative predictions of DOC behaviour are associated with an increase in the depth of infiltration of solutes with an increase in the seasonally thawed soil layer, which determines the sorption of DOC in the soil column and its microbiological destruction. An increase in the area and intensity of fires as a result of climate warming determines a significant transformation of the lateral carbon flux. At the same time, the observed reduction in river flow as a result of an increase in the pyrogenic factor will determine the overall decrease in the transport of terrigenous carbon from terrestrial landscapes.

The interaction of the main forest-forming species of Siberia: Siberian spruce ( Picea obovata Ledeb.), bush birch ( Betula fruticosa Pall.), Scots pine ( Pinus sylvestris L.), aspen ( Populus tremula L.), Siberian larch ( Larix sibirica Ledeb.), and Siberian stone pine ( Pinus sibirica Du Tour) with agro-gray soil is considered. The study is carried out in a special long-term experiment with forest crops, initiated by prof. N. V. Orlovskiy in 1968-69 in the southern taiga on the territory of the Kemchug Upland. It was revealed that biological characteristics and successional position of tree species significantly influence all components of the phytocenosis. The biggest changes were recorded under the canopy of early successional coniferous (larch) and small-leaved (birch and aspen) species, while late successional species - spruce and cedar - at this stage significantly limit the development of subordinate layers. Over the 45-year period of growth of forest crops, the soil profile is formed due to the differentiation of the arable substrate of the soil-forming species into genetic horizons. The influence of the forest canopy on planted agro-gray soil occurs gradually and intensifies with the growth and development of crops, the formation of a litter horizon and covers all soil properties. Active modern soil formation affects the mineral soil layer 0-10 (13) cm. Vertical flows of matter and energy entering the soil in the process of increasing capacity and intensity of the biological cycle are the main factor in the formation of the soil profile. The development of soil under forest crops under the conditions of a long-term zonal experiment was noted.

Two lime tree species: European - small-leaved lime ( Tilia cordata Mill.) and Far Eastern - amur lime ( Tilia amurensis Rupr.) grow in the arboretum of V. N. Sukachev Institute of Forest, Siberian Branch, Russian Academy of Sciences experimental station «Pogorelskiy Bor». Small-leaved lime tree has 9-16 m in height and 10-36.5 cm in diameter, amur lime tree has 11.5-14.5 m and 7.5-21.5 cm, accordingly. Plants of both species are characterized by high winter hardiness, they are not damaged with spring frosts and rarely attacked by pests. The lime trees begin blooming in the middle of July when the sum of effective temperatures reaches about 800 degrees/day (42.2-43.0 % of the total t _ef > 5 for the year). They continue blooming during 10-17 days. A fruits - lime-capsules ripen in September. The small-leaved lime tree capsules were 5.7 mm in length, 4.4 mm in width and 23.6 g in weight per 1000 pieces, its seeds were 4.0 mm, 3.0 mm and 14.5 g, accordingly. Sizes of amur lime tree capsules and seeds were similar - 5.3 mm, 3.9 mm and 23.8 g for the first ones and 3.9 mm 2.6 mm and 16.1 for the second ones. The part of empty seeds in small-leaved lime tree was 70 % but the part of such seeds in amur lime tree was 30 %. At the same time, the good quality of seed samples of both species did not exceed 30 %. On the territory of the arboretum there is natural regeneration of lime tree, including self-seeding. It is the most abundant at a distance of 50-100 m from the mother plants, where its density is 25-41 pieces per square meter.

The structure of the carbon pool in the middle-aged and mature pine stands of the Krasnoyarsk forest-steppe during care logging has been studied. The basis for calculations is data on the dynamics of the volume stocks of the stands. In accordance with the method of conversion coefficients, the phytomass of fractions (stem, bark, branches and needles) was calculated, which was then converted into carbon stocks. It has been established that the main contribution to the carbon pool of pine stands is made by stem wood. In medium-aged pine stands, the proportion of stems in the bark is 66-70 % of the total phytomass, and for mature stands this value is in the range of 76-80 %. The contribution of roots in medium-aged stands is about 20 %, and in mature stands 14-16 %. Branches and needles account for about 6.5 and 5.5 %, respectively, and in mature stands - 4.5-6.0 and 1.5-1.8 %. Felling residues account for about 13 % in medium-aged stands, and about 9 % in mature stands. In medium-aged and mature stands, when felling with an intensity of 15-20 %, it takes about 10 years to restore the carbon pool to the pre-cutting level. Felling residues in quantities proportional to the intensity of logging remain at the logging sites, and the carbon deposited in these fractions is an integral part of the ecosystem pool. In order to obtain the greatest increase in the phytomass of pine stands and minimize carbon losses during felling, selective logging using modern technologies for clearing felling areas and processing logging waste is most appropriate. It is possible to increase carbon absorption and minimize carbon dioxide emissions during felling of forest care by determining the intensity of optimal thinning of the tree stand.

The experience of a long-term study of the population dynamics of phyllophagous insects in Krasnoturansky pine forest (the southern part of Krasnoyarsk Krai) is discussed in the paper. Over the course of 40 years (1978-2016), regular counts of the abundance of five species of phyllophages were carried out in five landscape structures. Based on the data obtained, models of population dynamics of these species were proposed. The models were based on the idea of the existence of positive and negative feedbacks in populations. This approach made it possible to ignore the impact of parasites on insects. For calculations, an autoregressive (AR) model was proposed, according to which the current density linearly depends on the densities of previous years. The model coefficients were calculated using data from long-term surveys. It has been shown that most populations are characterized by the influence of the density of the past season on the current density in the form of a positive feedback and the influence on the current density of the density of the previous season in the form of a negative feedback. The characteristics of the stability of population dynamics of individual species in various habitats are considered. Stability margin indicators, widely used in control theory, were used as stability characteristics. It has been shown that the margin of resistance for sawflies (Tenthredinidae Latreille) is slightly greater than for other groups of species, which is consistent with the smaller dispersion of the population sizes of these species during long-term censuses. The use of AR models and characteristics of the stock of stability made it possible to classify landscape structures on the territory of the Krasnoturansky forest according to the risks of outbreaks of mass reproduction in these landscapes.

A review of the contents, processes of writing and reconstitution from manuscript materials of V. P. Grechkin’s monograph «Lesopathological characterization of the forests of the USSR by separate natural and geographical zones» is presented. Edited by Yu. I. Gninenko. In 3 volumes. VNIILM, 2019-2021.