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Herbivorous pests and arbuscular mycorrhizal fungi (AMF) coexist on the same host plant, having an indirect effect on one another. We established an experiment in a randomised complete block design with four treatments and six replications to examine the impact of AMF on the population and the damage caused to plane trees by the leafhopper Zyginella pulchra. Manure, manure plus fertiliser, manure plus fertiliser plus AMF, and non-inoculated plants (control) were all of the treatments. The findings revealed that while the nutritional content and soluble carbohydrate content were significantly enhanced by all treatments, they largely reached their peak in the AMF-inoculated plants. When compared to control trees that were not inoculated, the concentrations of N, P, and Zn were boosted by 39%, 81%, and 425%, respectively. AMF inoculation increased the population of Z. pulchra nymphs and adults compared to the control. However, the plants with AMF inoculation eventually suffered greater leaf loss as a result of this rise in the pest population. The findings show that while AMF enhance nutrient absorption and are necessary to improve the nutritional state of the host trees, they also enhance the absorption of pests that are thought to be harmful to plane trees. However, AMF colonisation improved the potential attractiveness of Z. pulchra to plane trees.

The ecological significance of Scots pine (Pinus sylvestris L.) in Europe, especially in areas devastated by bark beetles, has led to its consideration as a substitute for Norway spruce. This pioneering species boasts sun and drought tolerance, fast growth, and wood industry value. To gauge its potential, we examined two ecotypes across two test sites over two years, focusing on height and growth increment. Through statistical analysis employing R software and linear mixed models, we assessed heritability, genotype by environment interaction, and spatial correlations. Both ecotypes exhibited significant differences in height and increment, varying by year and site. Heritability was higher in the second year, with increment showing greater stability. Genetic correlations between sites were evident, suggesting stable increment ranking across locations. These findings underscore the role of ecotypic variation in Scots pine growth, advocating for its consideration in reforestation. Acknowledging such dynamics is vital for effective forest management and reforestation in Central Europe, promoting sustainability and informed decision-making. Further research will enhance this understanding of preserving and enhancing the region's tree populations.

The paper deals with a new method of innovative assessment of the supported effects and ecosystem services of forests using the actual amount of their increased costs. Among the most important research findings and significance of the new method is that it contributes to the body of knowledge on valuation and payment for ecosystem services. The focus of the research task is to help address the current difficult economic situation of forest owners resulting from the impacts of climate change. The study aims to determine what work quantifies the amount of compensation for the provision of supported ecosystem services that is sufficient for owners by using hypothesis testing. The evaluation of the supported effects was carried out in a case study in the area of the Chrudim-Podhůra Recreational Forests in the Czech Republic. The results of the evaluation were quantified in two experimental spreadsheets of the results, a comparative analysis of the evaluation results was performed, and hypothesis testing was conducted. The innovative methodological approach to the assessment of supported effects can be easily modified and used to assess the actual amount of increased costs of other ecosystem services of the forest.

Construction sector has high environmental impact throughout entire life cycle of buildings. One way to reduce the impact is to use building materials with the lowest possible environmental impact – such as wood. The use of wood-based building materials can improve the overall environmental balance of buildings. Compared to other materials, wood probably has the best environmental performance. These findings are particularly significant in the context of the environmental and legislative situation in Europe and the Czech Republic and may be one of the reasons for the increasing number of new wood-based buildings. The main reason for the research is to highlight the potential of wood as an ecological renewable material with multiple applications in all sectors of the national economy, especially in the construction industry. This paper aims to deepen the knowledge of the environmental specifications of building materials, especially wood, highlight its benefits and verify that building with natural and eco-friendly materials is less costly with lower environmental impacts. To illustrate the environmental impact of the construction industry, a case study comparing house variants was conducted to find the most suitable combinations of materials in terms of economic, environmental, and social aspects. It was found that from a sustainable development perspective, building with green materials generally means lower environmental impacts measured by e.g. global warming potential and embodied energy. This is particularly evident in the case of wood, which is not only a renewable material with advantageous thermo-technical and construction properties despite its low weight, but also stores carbon as it grows. The findings show that wood in the structure can reduce the cumulative environmental impact of the whole structure.

Designing and constructing a road network is one of the most critical steps of the development process in managing natural resources. The current research is going to investigate the application of network connectivity indices to the analysis of road networks in the forested watershed. First, the road network suitability map (RNSM) was created to emphasize the technical and physiographic criteria and integrated management scenarios using a weighted linear combination (WLC) and analytic network process (ANP). Subsequently, three road network alternatives (RNA) were assigned based on the priorities in the RNSM. In order to try to determine the appropriate alternative, the network connectivity of the designed alternatives looked into the forest and non-forest land uses, as well as the whole study area, using the values of alpha (α), beta (β), gamma (γ), eta (η), network density (ND) and detour indices (DI) in the context of the graph theory. Results show that the road density of the RNA2 variant (11.56 m·ha^–1) is shorter than the other alternatives and the existing road network (ERN). In addition, dealing with the whole study area, we realized that the index values which are related to the number two reflect a better status than the other alternatives of alpha, beta, gamma, eta and detour index, in which they were identified to be 0.44, 1.34, 1.16, 0.45 and 0.83, respectively. RNA2 is chosen as the appropriate road network according to the network connectivity, technical and physiographical criteria, along with integrated management scenarios. Further control measures and field surveys are recommended to achieve more relevant results.

The Ellenberg quotient (EQ) is a climate index defined as a ratio of the hottest month's temperature and the average annual precipitation sum. The quotient indirectly expresses the relationship between climate and vegetation, and its application is related to the ecological niche of Fagus sp. Although the quotient was curated on the grounds of field research primarily on German vegetation, the possibilities of its utilisation are not limited to the Central European region. The objective of this study is (i) to compare the EQ values calculated for the forest vegetation zones in the Czech Republic with the published data using the ecological niche of Fagus sylvatica; and (ii) to compare the new EQ-based vertical model with field empirical mapping. The study area is the Czech Republic, Central Europe. We used climate data from 1970–2000 and the data of the National Forest Inventory, 2^nd cycle (2011–2015), representing an objective data design. Geospatial analytic methods, machine learning (boosting), and verification through statistical testing were performed. The results indicate higher EQ values between the two most substantial spatial frames – the Hercynicum and Carpaticum regions. By comparing empirical mapped units to their climatic potential (in the EQ), a match was found only within the Carpaticum region. The study presents a concretisation of the general climate index for a specific region, adds to the knowledge about the Fagus ecological niche in context with the Central European vegetation, and also points to the EQ's potential for evaluating the concept of vertical differentiation of forest communities, as well as a possible prediction tool for the vegetation migration in context with climate change.

Biological diversity is the basis for a wide array of goods and services provided by forests. The variety of forest trees and shrubs plays a vital role in the daily life of forest communities. The purpose of this study is to investigate the possibility of modelling the diversity of tree species by characteristics of topography, soil and climate, using data mining algorithms k-NN, RF and SVM in Dr. Bahramnia forestry plan in the north of Iran. Based on the basal area factor for each species in a total of 518 sample plots, diversity indices such as species richness, evenness and heterogeneity were calculated for each plot. Topographic maps of primary and secondary properties were prepared using the digital elevation model. Categories of the soil and climate maps database of Dr. Bahramnia forestry plan were extracted. Modelling rates of tree and shrub species diversity using data mining algorithms, with 80% of the sampling plots were taken. Assessment of the model accuracy, using 20% of samples and evaluation criteria, was conducted. Results showed that topographic features, especially elevation, had the highest impact on the species diversity index. The modelling results also showed that Camargo evenness index had lowest root mean square error (RMSE) (0.14) and RMSE% (24.35), compared to other indicators of diversity. In addition, the results of the comparison between the algorithms showed that the random forest algorithms were more accurate in modelling the diversity.

The exact determination of the rotation period is still a current and important essential issue of forestry. It attracts the attention of forest economists, managers and owners worldwide, not only of forest economists but also of forest managers. The rotation period is defined by physical, technical or financial parameters of forest management. Therefore, it is necessary to distinguish between the biological and the economic optimal rotation period. A fundamental challenge in forest management is the need for appropriate determination of the rotation period. The primary interest of our research was to compare the effective legislation for the determination of the rotation period in the Czech Republic and in the Slovak Republic. Scientific methods such as document analysis and questionnaire survey were applied. The results of the legislation analysis and other related documents were compared with the expert opinions of the relevant stakeholders. Those who affect the decision process related to the problem and those where are "affected" by the problem were involved in the study. Results show that respondents do not agree with the regulation of rotation period according to effective law. Moreover, they consider it as not usable as the conditions in forest ecosystems have changed recently, which is not considered in the legislation.

This study analyses the perception of the relationship between forest certification and the production of ecosystem services by Programme for the Endorsement of Forest Certification (PEFC) and Forest Stewardship Council (FSC) sustainable forest management (SFM) certification holders. In addition, the psychological constructs that govern the use of certification for ecosystem services are investigated. Specifically, online questionnaire surveys were submitted to a sample of Italian and German forest owners and managers to study reasons for and against and global motives to adopt certification for ecosystem services through the application of Behavioural Reasoning Theory (BRT). Results show that respondents believe that certification can better support ecosystem services related to 'regulation and maintenance' and the conservation of biodiversity. On the other hand, the application of BRT has only been partially useful in explaining the psychological factors towards the adoption of ecosystem services certifications. In any case, attitudes and reasons for certainly had a significant influence on the intention to adopt certifications. Apart from the scientific implications, these results have practical applications for policymakers who can focus on the dissemination of the certification of ecosystem services by trying to support through eco-policies, the attitudes and reasons for expressed by forest owners.

Forest thinning can be used as an adaptive measure to improve the growth and resistance of Norway spruce forests affected by climate change. The impact of different thinning intensities on sap flow, growth, and tree water deficit of 40-year-old Norway spruce was tested. High thinning intensity (–61% of basal area) resulted in increased tree-level sap flow compared to the control (+27%), but it caused a decrease in the stand-level transpiration (–34%) due to reduced leaf area index. Low-intensity thinning (–28% basal area), high-intensity thinning, and control showed similar responses of sap flow to vapour pressure deficit and global radiation, suggesting unchanged isohydric behaviour. Both low- and high-intensity treatments displayed greater radial growth than the control. There were no differences in tree water deficit between the treatments. The low-intensity treatment can be considered the best water utilisation treatment with increased growth and unchanged transpiration at the tree level. The high-intensity treatment had similar radial growth as the low-intensity but lower stand-level transpiration, implying improved soil water availability. The study expands the ecophysiological understanding of thinning as a valuable silvicultural practice for adapting forest management of Norway spruce to the effects of climate change.

Juglans pyriformis Liebm. (Juglandaceae) is a threatened and endemic tree that grows in the cloud forest of Mexico. Natural populations of this species have been reduced due to, among others, changes in land use, overexploitation, and logging, with probable effects on its genetic diversity and structure. To determine the levels of variation and genetic structure of two populations with different silvicultural regimes, six inter-simple sequence repeat (ISSR) primers were used to amplify DNA from 35 individuals from a high-logging population and 32 from a low-logging population. The results show a higher polymorphism in the low-logging population (81.5%) compared to the high-logging population (77.4%). The genetic differentiation coefficient (PhiPT) values (0.109), genetic distance (0.134) and STRUCTURE analysis (Fst = 0.2271, P = 0.04) show significant genetic differentiation between populations. Rare, private, and monomorphic bands were detected in both populations. These results confirm the trend of reduced genetic variation due to logging.

While even-aged forestry is the dominating forest management system in Sweden, there is an increasing interest in Continuous Cover Forestry. Consequently, the conversion of even-aged stands into uneven-aged ones using e.g. selection cutting can be expected to become more common in Sweden. However, there are no up-to-date studies available on harvester productivity during selection cutting under Nordic conditions. Studying harvest intensity during selection cutting is of interest because lighter harvest intensities lead to higher volume growth and better-preserved forest ambience than heavier intensities. The objective of this study was to examine the effect of harvest intensity on harvester productivity during selection cutting. The field study entailed harvesting either 14%, 28% or 48% of a mature stand’s basal area. Harvester productivity was mainly explained by piece size (stem volume), while other factors, including harvest intensity, had only minor effects. This reality means that during selection cutting (thinning from above), piece size increases with decreasing harvest intensity, which in turn increases harvester productivity. Moreover, we observed a mild tendency that operators could select the stems’ felling directions and order more freely when fewer trees are harvested. This amelioration increases productivity additionally during lighter harvesting intensities.

To enhance the induction of shoots, the excised nodes were cultured on Murashige and Skoog medium containing different cytokinins and various concentrations. The best conditions for shoot induction and growth were with 6-benzyladenine at 1.0 mg.l^-1. For axillary shoot proliferation, the excellent result was obtained using 2.0 mg.l^-1 meta-topoline. Well-developed shoots (more than 2 cm in length) were successfully rooted ex vitro at 82% by treatment with commercial rooting powder (2% indole-3-butyric acid; Rhizopon®). Rooted plantlets were acclimatized in the greenhouse and the survival rate of transplantation reached 80%.

Interception, soil moisture and soil water potential were observed in four Norway spruce stands of different age in two subsequent vegetation seasons 2017 and 2018. Vegetation season 2018 can be characterized as being abnormally hot and dry with only 66% of precipitation in comparison with normal conditions. The interception of spruce increased with the stand age and its dimensions, ranging between 16 and 48% in 2017 and in the majority of stands even increasing in 2018. The soil moisture significantly decreased during the vegetation season 2018, with soil water potential close to the permanent wilting point (-1.5 MPa) for a substantial part of the monitored period. Differences between individual stands were observed in terms of the soil water potential (SWP) development which does not follow the interception patterns suggesting that the stand transpiration is a driving factor responsible for the soil water budget. In all stands, with the exception of the oldest one, the SWP of the upper soil horizon was less than 1.5 MPa for more than 80 days. In such extreme conditions the drought would negatively influence any Norway spruce stand regardless of its age or structure.

The extremely dynamic development of calamities caused by the effects of global climate change followed by the spread of under-bark insect pests mainly in coniferous stands and the ongoing incidental felling have raised concerns in the woodworking industry about the developments in the source material with respect to ensuring production in a short-term view. Since the overall standing stock in spruce stands of all age classes in the Czech Republic amounts to 399.6 million m³ (2017-2026) and the theoretical outlook of the logging potential based on the percentage of logging accounts for 112.62 million m³ (2017-2026), the concerns might be deemed justified. The article presents an updated view of the current situation based on official statistics and offers an analytic prediction of the possible development, considering the possible consequences, even in the production of the forestry sector. The statistical data on the current situation have been compiled for the last two decades of development. The results show that with a continued high rate of bark beetle calamities, assuming a total annual cutting with a permanent limitation on the planned harvests of more than 30 million m³, the complete stands of spruce from age class 5 onwards could be harvested in approximately 14-16 years.

Herbivorous ungulate diets affect population performance and overall forest health through balanced interactions on plant-herbivore relations; therefore, understanding them is critical. Faeces are frequently used in ungulate nutritional ecology because they can provide information about animals’ digestive efficiency. Roe deer (Capreolus capreolus) and red deer (Cervus elaphus) have different morpho-physiological and ecological constraints, and these differences should be reflected in their faeces. On the other hand, the lack of information about the animal (sex, age, reproductive status, diet selection, etc.) may be challenging for such studies. This study aimed to detect species’ different susceptibility to these factors reflected in animals’ faeces. Thus, we hypothesised that near-infrared reflectance spectrometry (NIRS) could distinguish between the faecal nutrients of two cervids. We collected 94 usable faeces from both species along the forest transect in Bohemian forests in the Czech Republic, covering 2 500 ha. Roe and red deer overlap was determined using the four faecal nutritional components on two axes. No discrimination occurred, refuting our hypothesis and highlighting that out-of-control variables are critical for faecal studies in uncontrolled settings. Fibrous parts explained the most variance (48%), indicating animals’ strong reliance on nutrition quality. Apparently, uncontrolled supplementary feeding produced similar faecal nutrient outcomes during the nutrition-limiting winter, which was theoretically supported by the animal’s response to predation and hunting pressure. The inability of NIRS to identify the source of N in faeces may also explain the lack of discrimination.

In some cases, it is difficult to promote climax tree species in the forest stand composition. In the Czech Republic, silver fir (Abies alba Mill.) is a typical example. This study offers an evaluation of the use of two improving compounds for tree plantations in the initial stage of growth in Central Bohemia. In the experiment, we measured the initial growth performance of a young fir plantation treated with a brassinolide compound (concentration 1 : 100 and 1 : 200) and Bio-Algeen^® prior to planting and compared it with control treatment: we assessed height, root collar diameter, vitality and mortality rate during the period 2014–2019. Cumulative mortality rate of the plantation reached 25% at the end of the monitoring period, without any significant differences between variants. Height increment of the variant treated with Bio-Algeen^® was significantly (P < 0.05) lower than the growth of brassinolide-treated variants, all treated variants were comparable with the control variant. The plantation underwent a drought-stress period in 2014 and 2015, which resulted in worsened vitality and colour across variants. As a result of the simple economic analysis, the most expensive inputs are planting stock and labour, therefore the price and application of additional substances should not affect decision-making.

This paper is focused on the description of the black mulberry (Morus nigra), its ecology and the possibilities of its in vitro propagation for quick and efficient obtaining of a large quantity of clones in a relatively short time for subsequent planting or sale. Due to ongoing climate change, it is considerable to use mulberry trees in horticulture, agroforestry and forestry under the conditions of Central Europe. The use of the mulberry is conditioned by the availability of planting stock. A proven and successful method of mulberry propagation is in vitro cultivation. Based on literature review, the recommended composition of planting media and other procedures for in vitro cultivation of mulberries are presented. The aim of the article is to inform foresters about the possibilities of using the black mulberry tree in our conditions and, using its example, to point out the possibility of using non-standard species of trees both as part of adaptation measures to the expected climate change and as one of the options for increasing the biodiversity of the landscape.

Local people’s socio-economic and natural resources, especially forest resources, have been affected by land degradation in Ethiopia in the past years. To combat this problem, rehabilitation of community-based degraded land has been performed since 1979. Rehabilitation of degraded land (RDL) is important for forest management strategy regarding the regeneration of degraded forests and related resources through women’s empowerment. Because empowered women are key users and managers of resources from rehabilitated land such as forest resources, which leads to sustainable utilization of forest products. The aim of the study was to evaluate women’s participation and empowerment in decision-making regarding the rehabilitation intervention. A total of 120 women households (60 user and 60 non-user
women) were selected using a stratified random sampling method. Data were collected using a household survey, focus group discussion and key informant interviews. The results revealed that there is a significant difference between user and non-user women in fetching water and fuelwood collection time. Furthermore, RDL contributes to improving user women’s economic status and social relationships such as livelihood opportunity, social network, build-up of trust and changes in social assets. The result also indicated that women able to participate in forest-related meetings, land use management, use and control of assets, decision-making, and in soil and water conservation measures. Further, user women had greater awareness compared to non-users due to participation in different meetings and other decision-making activities. The findings suggest that consideration of women’s participation in decision-making regarding the community land rehabilitation program is important to empower women equally with men.

Roads with the low standard level are often more susceptible to soil loss and production of sediment during rainfall events. The main aims of this research were to investigate the relationships between the standard level of the road and soil loss and determine the most effective road attributes in soil loss. Therefore, 30 road segments were selected in Bahramnia forest district, Golestan Province. These segments were classified into low standard, medium standard and high standard levels based on longitudinal slope, coverage on cut slopes, distance from runoff origin to culvert, traffic volume, and surfacing quality. A rubber bar was installed at the end of each segment to divert runoff into a sediment trap. In each trap, a series of wooden pins marked the locations for repeated elevation measurements of trapped sediment. Sediment volume was measured after each rainfall event. Results of the study showed that the most effective road attributes in soil loss were distance from runoff origin to trap and depth of ditch. Soil loss from road segments increased with the decreasing standard level of segments but this relationship was moderately strong (correlation coefficient: -0.45). An average amount of soil loss from low level standard road segments was 6.56 t.ha^-1.year^-1 while an amount of soil loss for high level standard roads was 2.66 t.ha^-1.year^-1. Indeed, by improving the road attributes and standard level, less sediment is produced from road segments.

The subject of this study is to point out the issue of various impacts of musculoskeletal disorders in chainsaw operators and their impact on human health. The first goal was to find out whether the body mass index is responsible for excessive stress to individual parts of the body of chainsaw operators at work. The second goal was to determine whether the excessive load to the individual body parts is affected by the time of working with the chainsaw. Questionnaires created for the fulfilment of the goals were distributed to professional forest loggers working in the Czech Republic, which were filled in by 161 of them. Questions in the first part of the questionnaire were formulated in such a way that answers to them would clearly identify information on the individual respondents. The second part of the questionnaire was focused on the assessment of the load upon 12 body parts of the operators (each part being split into the right and left sides). The results of the statistical analysis showed that neither the body mass index (BMI) nor the length of time working with the chainsaw affect the load on the individual parts of the body of the chainsaw operators.

Clear-cutting is the most common silvicultural system. Sometimes, if the new crop is not established successfully, clearcut is left unreforested. This study focused on a site where early successional species such as silver birch (Bi) and rowan (Ro) were accompanied with Norway spruce (Sp) in 13-year-old stand from natural regeneration at 550 m of altitude at an acidic site with eastern aspect and 25% slope. We found five types of stand composition: treeless gaps, Ro-Bi, Ro-Bi-Sp, Bi-Sp and monospecific Sp. Besides these juvenile ones, adjacent 100-year-old spruce (Sp old) stand representing pre-harvesting conditions was studied. In addition to the performance of trees, organic layer (Hum), topsoil (Ah) and upper subsoil (B) horizons were sampled to study an expected shift of chemical properties after clear-cutting and secondary succession at the site of interest. Birch dominated the natural regeneration; rowan and spruce were present mostly in understorey. Old spruce was more acidic and nutrient-poorer compared to the juvenile treatments. The treeless treatment showed also slightly higher pH and comparable nutrients compared to the young mixtures. Young spruce was higher in nitrogen compared to Ro-Bi-Sp mixture.

The Levels-of-Growing-Stock study for ponderosa pine was a collective effort among western Research Stations within the US Forest Service. The experiment was established to test sustainable productivity across a wide range of densities by periodically thinning the plots. Beyond the original purposes for wood production, contemporary applications of these long-term studies have been to determine stand density effects on (i) both overstory and understory responses to stand development of even-aged ponderosa pine, (ii) biomass accumulation and carbon sequestration, (iii) plant diversity and wildlife habitats, and (iv) forest resiliency to insects and pathogens, droughts, and wildfires. Furthermore, these installations have served as a showpiece for the public and natural laboratories for professional foresters and students. For the past half century, the study has helped guide land managers and stakeholders on public and private lands about the value of thinning in overstocked young stands of ponderosa pine across its range. We hope that it will continue to serve as a springboard for addressing future issues facing forest management.

We studied sessile oak (Quercus petraea) growing on six dry sites to understand adaptability responses to drought stress. Pedunculate oak (Quercus robur) on a moderately dry site was tested in parallel. We analyzed accessions from mostly dry sites that were less sensitive to soil drought and found that the growth performance ranking was not the same before and after treatment. We used phenological plasticity approaches to study seed development and plant development before and after drought: the treatments included stem length, root length, and collar diameter, as well as dry above- and below-ground biomass performance. Additionally, after drought treatment, osmolytes and root surface were tested in Q. petraea. According to the analyses and results, the ranked sites did not maintain their ranking status, with Q. petraea exhibiting different rates of growth during each developmental stage from seed development until the end of the treatment of plant material. The smallest seeds came from the driest site, which may indicate more adaptability to drought stress. After drought treatment, large differences were found between the dry biomass performance, stem length, root length, and collar diameter of oaks grown on different sites. The osmolality of Q. petraea on most of the dry sites was higher under the reduced treatment than under the optimal treatment, but not significantly. After drought treatment, all accessions - and especially those from the driest site - showed large differences in growth performance between the treatments. The relationship between seed weight and seedling development before and after drought treatment differed according to the developmental stage.

Micropropagation has enormous potential in the forestry industry for the mass production of elite genotypes. A limiting factor that hinders a wider adoption of this technique is its high associated cost, dissuading small producers and laboratories from its use. Thus, it is important to develop low-cost protocols to increase the competitiveness of micropropagation. The goal of the present study was to elaborate a low-cost culture medium that would allow plant growth without diminishing plant quality and production. The replacement of laboratory sucrose with commercial sugar as a carbon source, and laboratory agar with locally produced agar as a gelling agent was tested. To validate the effects of the medium for woody species micropropagation, two relevant forest species, chestnut and birch, were used and several phenotypic characteristics were recorded. Our data indicated that the substitutions made in the media composition did not alter growth or rooting parameters. Substitution of laboratory sucrose and Bacto agar by table sugar and local commercial agar provides a valuable alternative for forest species micropropagation and for increasing their potential profitability.

In this paper, empirical relationships between diameter at breast height (DBH), crown diameter (CD), and stem number per hectare (N) were improved in a Paulownia Shan Tong plantation. Various functions of these variables were defined, focusing on growing space (G_s) and stem number per hectare. The linear crown index between CD and DBH seems to be particularly important in predicting stem number per hectare. Based on an analysis of the relationships, a CD-DBH (R² = 0.7254) and a DBH-N graphic model (R² = 0.7302) can be applied widely in plantation forestry. Under suitable site conditions, the investigated Paulownia hybrid can provide a higher increment in DBH than most of poplar hybrids at a certain age. The aim of this study was to explore the relationships between the G_s based on CD and DBH. These types of investigations are of fundamental importance in terms of the growing technology of tree plantations.

Mountain ecosystems, especially those at the highest altitudes, are sensitive to current climate change. Proxy archives may provide an insightful tool to better understand ongoing changes and evaluate future scenarios. Trees have traditionally been used as such archives, as they often respond sensitively to environmental change. Thus, we studied tree-ring records of forest-line species Abies densa Griff. growing in the Eastern Himalayas, central Bhutan, to evaluate the effect of climate on the growth of this species. The annual chronologies were generated using standard dendrochronological methods and then compared with climatic data from the CRU TS database. The results demonstrate a negative effect of summer temperatures on the width of the annual rings, suggesting possible stress caused by higher temperatures during the monsoon season. On the other hand, a positive effect of temperatures on tree growth was observed during late winter months. The response to rainfall was mixed, with a positive effect on growth in November and a negative effect in May and January, suggesting a later onset of the vegetation season. To our knowledge, we present the first dendroclimatological study on this long-lived species in central Bhutan, portraying its potential for future climate and environmental research and applications.

Seedling quality is an important input affecting the outplanted seedling performance. Morphological attributes and association with symbiotic ectomycorrhizal (ECM) fungi belong to influential traits determining seedling quality. In this study, the effect of pre-sowing applied commercial additives Ectovit (containing hydrogel and ECM fungi), Mycorrhizaroots (ECM fungi and nutrients) and Vetozen (natural mineral fertilizer) on the growth and ectomycorrhiza formation of Norway spruce seedlings grown in nutrient-poor pure peat in an open nursery site was assessed. Two-year-old bareroot seedlings were transplanted into containers. No significant growth differences were detected between treatments for 1 + 0 seedlings but the values of growth parameters (root collar diameter; stem height; shoot, root and total dry weight) of Ectovit-inoculated seedlings were significantly higher than those in the other treatments including the control after the second (2 + 0 seedlings) and the third growing season (2 + 1). Root-to-shoot dry weight ratio and number of root tips were distinctly higher after the third year compared to the previous two years but they were not significantly different between treatments. Mycorrhizaroots and Vetozen did not have any significant effect on seedling development. Although the occurrence of treatment-specific ECM morphotype was detected in Ectovit-inoculated seedlings, the high total ECM colonization of roots in all treatments including the control indicated a crucial impact of naturally occurring fungi on ectomycorrhiza formation.

In this study, the first observation of Thanasimus femoralis was conducted in Türkiye. Adults of T. femoralis and Thanasimus formicarius were collected from pheromone traps together with Ips sexdentatus, Ips acuminatus, Ips mannsfeldi and Scolytus intricatus in forest nurseries located in the Western Black Sea Region, between 2021 and 2022. The clerid and bark beetles were morphologically described. The aedeagus and antennae of T. femoralis were observed by scanning electron microscopy.

Soil nitrogen (N) cycling plays a pivotal role in forest ecosystem productivity and nutrient regulation. This review synthesises recent advances in understanding how forest management practices influence soil nitrogen cycling and highlights future research priorities for elucidating underlying mechanisms and optimising forest ecosystem functioning (Figure 1). Management interventions such as thinning, species composition adjustment, and understory vegetation control have been shown to affect N inputs and transformation pathways by modifying litter quality, microbial community structure, and N-cycling enzyme activities. However, current findings remain inconsistent, and mechanistic insights are still limited. Future research should focus on disentangling the multi-scale, multifactorial interactions through which forest management regulates soil N cycling. Integrative approaches that link molecular biology with ecosystem-level processes are needed to clarify the interplay among microbial dynamics, enzyme activity, root exudates, and soil physicochemical properties across spatial and temporal scales. In addition, research should explore how forest management affects community structure, litter inputs, soil aggregation, and subsurface biochemical processes to reveal the synergistic regulation of nitrogen cycling by biological, physical, and chemical drivers. Establishing long-term monitoring networks across a range of forest types and climatic regimes, combined with tools such as metagenomics, high-throughput sequencing, and stable isotope tracing, will enable the precise characterisation of key nitrogen-cycling genes and fluxes. In the context of global environmental change, it is also crucial to assess how forest management modulates the coupling of nitrogen, carbon, and water cycles and the resultant ecological feedbacks.