Siberian Journal of Forest Science

The small spruce bark beetle ( Ips amitinus (Eichhoff)) is the European species which invaded Siberia providing outbreaks in forests predominated by its new host plant, the Siberian pine ( Pinus sibirica Du Tour). The barrier pheromone traps with dispensers containing synthetic aggregation pheromone of small spruce bark beetle produced by the Russian Quarantine Center (VNIIKR) and the Austrian company Witasek were placed in the pest foci in the Siberian pine forest of the Tomsk Region and regularly checked in June-August 2024. During the period of bark beetle flight, the synthetic pheromones of Russian and Austrian producers attracted no one small spruce bark beetle specimen. Instead, the Russian pheromone attracted specialized entomophagous predator Thanasius femoralis (Zetterstedt) and a number of non-target species of bark beetles and sawyer beetles. The catches on the Austrian pheromone were indistinguishable from control traps in terms of the composition of attracted insect species. The necessity of additional research on the development of efficient pheromone mixtures for monitoring small spruce bark beetle in its secondary range is emphasized.

On average, in Siberia about 600 thousand hectares of forests have been annually cut down in the last two decades and about the same much damage from forest fires. Furthermore, forest stands have been damaged by pests (Siberian silkworm ( Dendrolimus sibiricus Tschetverikov), four-eyed fir bark beetle ( Polygraphus proximus Blandford), etc.) as well as windfalls and industrial emissions. Forest cover significant changes indicate the need identifying the causes of those changes for the purpose of eliminating negative phenomena. The forest fund dynamics disclose a deterioration of the qualitative species composition. The reasons for this are not only global climate warming, but and quite predictable human and natural factors: logging, forest fires, forest insect outbreaks, natural forest regeneration processes, and forest land transfers for infrastructure development. Forestry in Russia is still far from solving the problem of full-fledged forest reproduction. Forest reproduction involves a number of stages that must be consistently implemented to achieve the final goal. Reproduction of forest resources is preceded by the process of reforestation, which involves the restoration of cut, dead or damaged forests and which ensures the formation of a closed young forest, but does not guarantee the necessary structure and target functions of a mature forest. The latter can be achieved through subsequent forestry measures, including thinning, forest protection and conservation. The long period of forest regeneration calls for the need for decision-making, which results will be achieved in many decades later. The action system should be aimed at adapting forests to predicted natural and economic transformations.

Global climate change, anthropogenic pollution, the development of epiphytotics and the mass reproduction of insect pests are the cause of the phytopathological state of tree species stands. To the understanding of the pathology mechanisms development of the tree’s structural elements (in particular, needles) will be promote analytical approach to the study of the tested plant organ. The study approach was implemented by us using the example of a comparative study of healthy and damaged Scots pine ( Pinus sylvestris L.) needles from suburban stands using infrared Fourier spectroscopy. The analysis of the IR spectra of healthy and damaged needles is based on a method for comparing the intensity ratios of absorption bands at characteristic frequencies (for bonds, functional groups, and the type of their oscillations). The assignment of absorption bands was carried out according to the literature data. In order to compare damaged samples of needles with the control, the absorption band intensity ratio was calculated for I 1375/2900, I 1695/1647, I 1506/898, I 1564/1550, I 1695/1533, I 1447/1369, I 1654/1730, I 1728/1477, I 2920/1600, I 3040/1600, I 3040/1508, I 1512/894 (subscripts indicate for which wave numbers the absorption intensity ratios were calculated). The analysis of the IR spectra needles array using this method showed what changes (qualitatively and quantitatively) at the level of molecular and structural parameters are characterized by shrinking and diseased needles compared with healthy ones.

Dwarf birch ( Betula nana L.) is a circumpolar low shrub common in the northern hemisphere. Previously, it was suggested that dwarf birch hybridize with a sympathetic species - the downy birch ( Betula pubescens Ehrh.), with the formation of triploid hybrids in the northern regions of Western Eurasia. Data on the presence and intensity of these species hybridization on the territory of the Russian Federation are scarce and require additional study and verification. The purpose of this study was to study the ploidy level of some birch representatives growing in the mountain tundra of the Altai Mountain range to identify hybrid forms. The work used the flow cytometry method in combination with the analysis of nuclear microsatellite loci. The average DNA content of the studied dwarf birch and silver birch ( B. pendula Roth) samples was 2С = 0.966 pg and 2С = 0.974 pg correspondingly, while DNA content of the putative hybrid sample was 1.46 times higher 2C = 1.413 pg, indicating its probable triploid genome. Analysis of nuclear microsatellite loci confirmed the data obtained by flow cytometry. It was shown that nuclear loci L3.1, L7.3, L1.10, L5.4 are most suitable for identifying triploid hybrid birch samples. The work performed confirms the existence of rare triploid hybrids dwarf birch and downy birch in populations of dwarf birch trees growing in the mountain tundra forest in Altai. The analysis shows that the flow cytometry method in combination with microsatellite analysis is an effective tool for searching and verifying triploid birch hybrids.

Based on materials of trial plots, it has been analyzed the consequences of strip-gradual felling (SFG) of derivative forests on the territory of birch derivatives of the southern taiga forest region (the European part of the Russian Federation within the borders of the Republic of Udmurtia). It has been established that in the presence of coniferous undergrowth of addition to pregeneration and its preservation during logging operations it is ensured the formation of young spruce stands in place of derivative birch plantations without artificial forest restoration. In addition to preserving the pre-generation coniferous undergrowth, it is important to minimize the area of skidding roads, since even 25 years after cutting there is no undergrowth of coniferous species on them. In order to preserve undergrowth and coniferous trees it is advisable to place logging residues on skidding tracks, they increasing the bearing capacity of the soil. The destruction of teenage coniferous trees in the process of carrying out adjacent work contributes overgrowth of cut down strips with soft deciduous trees and living soil cover. Coniferous undergrowth of accompanying generation in stripes left for the second appointment is not accumulated due to the high density of the tree canopy of a two years planting but in the cut down strips of the first cut down strips appointment due to high competition from 2Sc undergrowth and softwood trees. In the absence of coniferous undergrown preliminary generation is advisable to carry out 5-7 before the first SFG for the purpose of accumulating coniferous undergrowth.

There are very few works in the scientific literature based on the results of long-term introduction. In this regard, the data obtained on stands in protected areas (objects of landscape art), which include introduced rocks in their compositions, are important both from a theoretical and practical point of view. Plantings at the objects of landscape art, in this regard, are actually a scientific, industrial and educational base. The objects of the study were old-age trees growing on 18 sites of specially protected natural territories of Vologda Oblast. It was found that 74 % of the compared tree-ring chronologies, taking into account forest growing areas, have a lack of communication, 16 % have a low connection, 10 % have an average one. Based on the denrochronological and dendroclimatic analysis, the relative contribution of various factors, taking into account the biological characteristics of tree species, to the formation of annual rings has been established. There is a positive reaction (response by radial increment) to the sum of positive temperatures in pedunculate oak ( Quercus robur L.) and small-leaved linden ( Tilia cordata Mill.) at values above 2000 °C. In turn, a negative response was recorded in Siberian larch and Siberian pine at a total effective temperature of less than 1900 °C. For Siberian pine, it was found that with a precipitation level of more than 300 mm and with the sum of effective temperatures for the growing season less than 2000 °C, an increase in radial growth is noted. The performed study allowed us to conclude that not for all introduced tree species, the thermal regime in the European North is a limiting factor, which is important for the introduction of introduced tree species into the crops in the region under consideration. The lack of timely care for stands in protected areas, an unsuccessful combination of tree species and agrotechnics of the formation of these objects affected the slowdown in growth rates, especially at the initial stages of growth and development of innoregional species, the obtained tree-ring chronologies were obtained for the region for the first time, they are characterized by high synchronicity with each other when compared. These data allow us to assert the existence of connections and general patterns in the growth and development of plants, regardless of their territorial location, and all differences are related only to the individual characteristics of the growth and development of each tree species.

The article analyzes and updates the features of the functioning of the transport and technological system for the supply of commercial wood and supply chain management, and identifies the main parameters for optimizing the supply chain management system for commercial wood to ensure the efficiency of the process. A multi-criteria approach to assessing the efficiency of the transport and technological process of supplying commercial timber is proposed due to the inconsistency of the main indicators that determine its effectiveness. A mathematical model has been developed for a complex multi-criteria assessment of the efficiency of the transport and technological process of supplying commercial wood, based on: methods of linear and dynamic programming, stochastic and economic-mathematical modeling, elements of statistical and economic analysis. The combination of the mentioned modeling methods allows the model to be quite simple and reliable in practical application, as well as adaptive to the changing external conditions of the production environment. The methodological development is presented with a detailed description of all the dependencies included in it, and the advantages of its application are noted.