Лесное хозяйство. Деревообрабатывающая промышленность

As forests in Bosnia and Herzegovina cover 2,904,600 ha or 56.7 % of its total area, and since the meteorological data analysis for the period 1961–2014 shows that the mean annual temperature maintains a continuous rise, сlose attention should be paid to these fragile ecosystems. It is important to note that one of the most economically valuable species for forestry in Bosnia and Herzegovina, Norway spruce, is particularly endangered due to its very low drought resistance and spread of various diseases. Comparing the last climate sequence (1991–2019) with the previous one (1961–1990) we found that the spruce-inhabited areas showed an average increase in the values of the Forest Aridity Index of 0.929. As for the Ellenberg’s climate quotient, it is noticeable that climate change is not as strong as in the case of the Forest Aridity Index. Based on projections for the mid- (2041–2070) and late-century (2071–2100) under the RCP 4.5, there will be no change that is likely to significantly affect the distribution of spruce. The predicted rates of decline and altitudinal shifts of favorable habitats are negligible. On the contrary, projections under the RCP 8.5 predict a significant reduction of suitable habitats, both for the existing range of Norway spruce and the entire territory of Bosnia and Herzegovina. Particularly, late-century projection under the RCP 8.5 predicts an almost complete reduction of suitable habitats, while small areas of suitable habitats at higher elevations will remain intact. For citation: Miletić B., Drašković B., Đorem T., Bojić S., Matović B., Stojanović D.B. The Potential Impact of Climate Change on the Distribution of Norway Spruce (Picea abies Karst.) in Bosnia and Herzegovina. Lesnoy Zhurnal [Russian Forestry Journal], 2022, no. 2, pp. 73–83. DOI: 10.37482/0536-1036-2022-2-73-83

The technological processes of treatment of biomass into prospective materials are considered in the textbook. Intended for Master’s Degree Students of the Faculty of Power Engineering and Technological Equipment of the direction of training 35.04.02 «Technology of logging and wood processing industries» under the training program «Energy-saving technologies for processing forest resources into promising materials» (the discipline is «Basics of special methods of biomass processing into prospective materials»), as well as for post-graduate students and teachers.

This work presents the results of a research that was conducted in the Donskoy Leskhoz nursery of the Forestry Department of the Lipetsk Region. The purpose of the research is to determine the effectiveness of the influence of a low-frequency electromagnetic field and the hydrogel “Evabiona” on the survival rate of red oak annual seedlings grown in open ground of the nursery. This research presents the technology for creating red oak planting material with increased survival indices of test samples and their biometric parameters: seedling height, seedling diameter at a root collar, weight of roots and aboveground part in the air-dry condition after drying for 15 days. Treatment of red oak one-year old seedlings with a low frequency electromagnetic field was carried out according to the author’s technology POSEP – pre-sowing treatment of seeds and seedlings with an electromagnetic field. The hydrogel, a polymer water-retaining agent that absorbs and retains a large amount of moisture in the rhizosphere of plants, was applied to soil in the experimental research. The ability of the hydrogel granules to swell-compression improves the structure and drainage of soils, boosting the conditions of aeration and filtration of water, and maintains its waterretaining properties for several years. The research results indicate a clear positive effect of treatment with a low-frequency electromagnetic field and the hydrogel, as there was a significant increase in the survival rate of the test samples of oak seedlings in relation to the control samples. Also within the framework of the research a comparative histometric analysis of cross sections of control and test stems of oak seedlings was carried out late in the growing season at the laboratory of the Department of Forest Crops, Selection and Dendrology of the Mytishchi Branch of the Bauman Moscow State Technical University. The results of this research showed that a low-frequency electromagnetic field and the hydrogel can influence on the anatomical structure of seedlings, improving their quality characteristics. Thus, pre-sowing treatment of oak seedlings with a low-frequency electromagnetic field and the use of the hydrogel showed the effectiveness of these techniques in increasing the survival rate of seedlings and obtaining high-quality planting material of red oak in forest nurseries. For citation: Smirnov A.I., Orlov F.S., Aksenov P.A., Yaskov Yu.V. The Effectiveness of Low Frequency Electromagnetic Field and Hydrogel Influence on Survival Rate and Growth of Red Oak (Quercus rubra L.) Annual Seedlings. Lesnoy Zhurnal [Russian Forestry Journal], 2020, no. 5, pp. 81–89. DOI: 10.37482/0536-1036-2020-5-81-89
В настоящей работе представлены результаты исследования, которое проводилось в лесном питомнике Донского лесхоза Управления лесного хозяйства Липецкой области. Цель исследования определить как гидрогель «Эвабиона» и низкочастотное электромагнитное поле (ЭМП) влияют на приживаемость и рост однолетних сеянцев дуба красного в открытом грунте питомника. В работе приведена технология создания посадочного материала дуба красного с повышенными показателями приживаемости опытных образцов и их биометрических характеристик: высота сеянца, диаметр сеянца у корневой шейки, масса корней и надземной части в воздушно-сухом состоянии после высушивания в течение 15 дней. Обработка однолетних сеянцев дуба красного низкочастотным электромагнитным полем проводилась по авторской технологии ПОСЭП (предпосевная обработка семян и сеянцев электромагнитным полем). В постановке опытов применялся гидрогель «Эвабиона», полимерный влагоудерживатель, который при внесении в почву, абсорбирует и удерживает большое количество влаги в зоне ризосферы растений. Способность гранул гидрогеля к разбуханию-сжатию улучшает структуру и дренаж почв, повышая условия аэрации и фильтрации воды, сохраняет свои влагоудерживающие свойства в течение нескольких лет. Полученные результаты исследования свидетельствуют о явном положительном влиянии обработки электромагнитным полем и гидрогелем, так как отмечено существенное увеличение приживаемости опытных образцов сеянцев дуба по отношению к контролю, также в рамках исследования, в конце вегетационного сезона в лаборатории кафедры лесных культур, селекции и дендрологии Мытищинского филиала МГТУ им. Н.Э. Баумана был проведен сравнительный гистометрический анализ поперечных срезов контрольных и опытных стволиков сеянцев дуба. Результаты этого исследования показали, что электромагнитное поле и гидрогель могут оказывать влияние на анатомическое строение сеянцев, улучшая их качественные характеристики. Таким образом, предпосадочная обработка сеянцев дуба низкочастотным электромагнитным полем и применение гидрогеля показали эффективность данных приемов для увеличения приживаемости сеянцев и получения качественного посадочного материала дуба красного в лесных питомниках. Для цитирования: Smirnov A.I., Orlov F.S., Aksenov P.A., Yaskov Yu.V. The Effectiveness of Low Frequency Electromagnetic Field and Hydrogel Influence on Survival Rate and Growth of Red Oak (Quercus rubra L.) Annual Seedlings // Изв. вузов. Лесн. журн. 2020. № 5. С. 81–89. DOI: 10.37482/0536-1036-2020-5-81-89

A physical model is developed for heating a set of laminated cellular structure formed from peeled veneer, dependences for determining its thermal conductivity under conditions of non-stationary heat transfer are proposed. It was found that for a package of 11 layers of birch veneer 2 mm thick, the thermal diffusivity is 1.93∙10–6 m2/s. Based on the fundamental theory of thermal conductivity of the wood substance, dependencies are obtained for calculating the duration of bonding of heat-insulating materials of a cellular structure. It has been established that the duration of gluing of a 22 mm thick plywood mesh slab of peeled birch veneer under pressure exposure is 14.5 minutes at a temperature of press plates 110 °C. The thermotechnical characteristics of the new wood-based cellular structure material were determined: the thermal conductivity coefficient of a cellular plywood board with a density of 530 kg/m3 was 0.081 W/(m·K), the strength under static bending of the board parallel to the fibers of the outer layers was 14 MPa, and perpendicular to the fibers was 10 MPa. The use of underutilized soft broadleaved species with low operational properties as a heat-insulating material, where high strength indicators are not required, is justified, since its thermal conductivity is two times lower than that of a similar material – solid plywood board. For citation: Lukash A.A., Lukutsova N.P. Thermal Conductivity of Wood-Based Cellular Structures. Lesnoy Zhurnal [Russian Forestry Journal], 2020, no. 1, pp. 146–153. DOI: 10.37482/0536-1036-2020-1-146-153
DOI: 10.37482/0536-1036-2020-1-146-153.