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Climate change and topographic variations affect infestation by Xyleutes ceramica (Walker, 1865) (Lepidoptera: Cossidae) in teak plantations in ThailandOriginal PaperThanapol Choochuen, Jiøí Foit, Ponthep Meunpong, Warong SuksavateJ. For. Sci., 2025, 71(6):297-311 | DOI: 10.17221/15/2025-JFS The teak bee-hole borer [Xyleutes ceramica (Walker, 1865)] is considered one of the most serious pests of teak (Tectona grandis) in Thailand. The present study investigates climatic and topographic variables affecting the infestation of teak trees by X. ceramica in 10 plantations and predicts the risk of infestation by the species under current and future climatic conditions in Thailand. At each plantation, 48 plots evenly distributed among twelve teak stands were sampled. The infested teak trees in the plots were assessed, and the coordinates of the tree positions were recorded. The maximum entropy (MaxEnt) model was used to assess the effects of environmental factors and predict the occurrence probability of the species using current and projected (2050) climate data based on the Shared Socioeconomic Pathways SSP1-2.6 and SSP5-8.5 scenarios from multiple global climate models. According to our results, high accuracy values [AUC (area under the curve) = 0.852, TSS (true skill statistics) = 0.775] of the model prediction were obtained, and the infestation was found to be driven much more by climate than by topographic characteristics. Above all, X. ceramica was found to prefer moderate temperatures in a highly distinct seasonal climate. Additionally, relatively low amounts of premonsoon rainfall are also found to be favoured by the species. The predicted risk map revealed that the northern region is the core area of X. ceramica infestation in Thailand under current and future climatic conditions, but the severity of infestation is predicted to gradually decrease under the predicted future climatic conditions. Recommendations for management to minimise tree damage caused by X. ceramica are also presented in this study. |
Impact of technical water retention on European beech (Fagus sylvatica L.) resilience and growth dynamicsOriginal PaperZdenìk Vacek, Ivana Tomá¹ková, Zdenìk Fuchs, Václav ©imùnek, Stanislav Vacek, Jan Cukor, Luká¹ Bílek, Josef Gallo, Karel Zlatu¹ka, Martin DuchanJ. For. Sci., 2025, 71(3):124-137 | DOI: 10.17221/92/2024-JFS Global climate change (GCC) is putting increasing pressure on forest ecosystems, leading to more frequent disturbances such as pest outbreaks and other climate-related stressors, all of which threaten forest stability. This study examines how different technical water retention measures (infiltration pits) can enhance the resilience of European beech (Fagus sylvatica L.) to these climatic challenges, focusing on their impact on radial growth, sap flow, and acclimatisation to moisture conditions at two sites in Czechia (430–440 m a.s.l.). Three treatments were compared: a water infiltration pit under a culvert mouth, an infiltration pit without a culvert and a control plot without a technical solution. Results showed that maximum daily transpiration rates of beech ranged between 90–120 L per day. Air temperature had a stronger influence on beech radial growth than precipitation, particularly at the waterlogged sites. The lowest radial growth occurred in the treatment involving a water infiltration pit under a culvert mouth, while treatments with an infiltration pit without a culvert demonstrated notable seasonal stem shrinkage and swelling (tree water deficit – TWD), especially in early spring. On the other hand, no differences were found between the three treatments including the control variant in the maximum growth or the context of minimum TWD. In conclusion, these technical measures had limited or short-term effects on the growth and physiological processes of European beech. Despite the high costs of implementation, sap flow and dendrochronological measurements do not support the construction of infiltration pits as a means of improving water retention in forest ecosystems. |
Comparison of shelterwood and clear-cut regeneration methods on morphological traits of naturally regenerated sessile oak [Quercus petraea (Matt.) Liebl.] seedlingsOriginal PaperEli¹ka ®i¾ková, Martin Kománek, Dominika Krausková, Jakub ÈernýJ. For. Sci., 2025, 71(11):542-554 | DOI: 10.17221/77/2025-JFS The natural regeneration of the sessile oak [Quercus petraea (Matt.) Liebl.] is an important aspect of sustainable forest management, especially given the ongoing global climate change and the need to maintain forest stand stability and productivity. This study aimed to evaluate the effect of various regeneration methods on the growth of naturally regenerated sessile oak in the Masaryk Forest Training Enterprise Køtiny, Czech Republic. The research was conducted in seven forest stands where regeneration felling was applied after masting in 2022 (winter 2022/2023) using clear-cut (CC) and shelterwood (S) systems. A total of 531 seedlings were collected from these seven research plots, and the following morphological traits were measured: shoot length, root collar diameter, and biomass allocation. Statistical analysis revealed significant differences (P < 0.05) in shoot length, main root length and total seedling length between the CC and S variants. However, there were no significant differences in root collar diameter or any of the dry-mass parameters between the clear-cut with standards (CC1) variant and the shelterwood plots. Individuals from the CC variants have a 10.3–47.0% wider root collar diameter, 22.3–91.4% more dry mass of the root system, and 51.7–90.4% more dry mass of the aboveground part than individuals in the S variants. These results indicate that the early growth of sessile oak seedlings is greatly influenced by light availability: full sunlight stimulates the development of above- and below-ground parts, whereas canopy cover restricts early growth, particularly in terms of height. The findings highlight the need to consider light and site conditions when planning silvicultural treatments aimed at establishing stable and vigorous oak stands in the face of changing climate conditions. |
Changes in volatile organic compounds (VOCs) content in resistant and non-resistant forest trees in response to bark beetle attackOriginal PaperPetr Soudek, Jan Rezek, Kateøina Mo»ková, ©árka Petrová, Pavlína Máchová, Adam Véle, Martin Fulín, Petr Ho¹ekJ. For. Sci., 2025, 71(5):218-236 | DOI: 10.17221/4/2025-JFS Corrigendum in: J. For. Sci. 2026 Feb 27;72(2):106. doi: 10.17221/16/2026-JFS |
Tree growth and soil recovery in Amazonian lands degraded by coca cultivation and grazingOriginal PaperLuis Walther Espinoza-Ambicho, Luis Alberto Valdivia-Espinoza, Warren Ríos-García, Martin Valtera, Luis Alberto Valdivia-Ruiz, Tito Felipe González-Manrique de Lara, Lenka EhrenbergerováJ. For. Sci., 2025, 71(8):393-405 | DOI: 10.17221/47/2025-JFS Soil degradation resulting from illicit coca cultivation and unsustainable grazing practices poses a major challenge to ecosystem restoration in the Peruvian Amazon. This study evaluates the potential of fast-growing tree species to rehabilitate degraded soils while producing economically valuable timber. Monoculture plantations of Corymbia torelliana (eucalyptus), Calycophyllum spruceanum (capirona), Colubrina glandulosa (shaina), and Cedrelinga cateniformis (tornillo) were established on former coca and pasture lands in the Alto Huallaga Valley. We assessed tree growth and key soil physicochemical properties – including soil organic matter (SOM), bulk density (BD), pH, extractable phosphorus (P), and cation exchange capacity (CEC) – in topsoil (0–10 cm) and subsoil (10–40 cm) layers. Eucalyptus and tornillo showed the highest diameter growth, while tornillo plots had significantly higher SOM levels. Soil pH was strongly acidic across all plots, and subsoil P was lowest under tornillo. CEC was highest in eucalyptus and capirona plots. Our findings suggest that tree plantations, particularly with eucalyptus, capirona, and tornillo, represent a viable strategy for the sustainable use and rehabilitation of soils formerly used for coca cultivation and grazing. |
Changes in the concentration of CO2 in forest soils resulting from the traffic of logging machinesOriginal PaperLubo¹ Stanìk, Jindøich Neruda, Radomír UlrichJ. For. Sci., 2025, 71(5):250-267 | DOI: 10.17221/6/2025-JFS The aim of the study was to find out whether and how the forest soil compaction resulting from the traffic of forest logging machines results in the increased soil air concentration of CO2, occurring over a longer period of time and in different seasons of the year. Changes in the soil air CO2 concentrations were monitored in two periods: in winter (cold period) and in summer (warm period). CO2 concentrations were measured in compacted and non-compacted soil using a certified measurement. In addition to the soil concentration of CO2, air temperature, soil temperature and soil moisture content were measured. The research was conducted in the Czech Republic. The obtained data was subjected to statistical analyses (Student's t-test; correlation analysis). The results of the study confirm the long-term influence of soil compaction by the traffic of forest machinery on the CO2 concentration in soil in both seasons (cold and warm). The concentration of CO2 in the air of compacted soil was always significantly higher in both periods than the CO2 concentration in the air of non-compacted soil (control). Thus, the negative influence of soil compaction was clearly demonstrated as a result of a single pass of forestry machines over the soil surface. |
Potential of Thuja plicata and Chamaecyparis lawsoniana in the context of global climate change in the Czech RepublicOriginal PaperPavel Horák, Petra Jablonická, Robert KnottJ. For. Sci., 2025, 71(9):426-440 | DOI: 10.17221/51/2025-JFS The introduction of non-native tree species is considered a potential adaptation strategy to global climate change (GCC) in the forestry sector. As some of the most widespread native species are undergoing stand disintegration due to both abiotic and biotic stressors, the search for alternative species becomes essential. These species can overwhelm native species with both production potential and adaptation to a changing climate. The research focused on climate-growth relationships of two introduced species of the Cupressaceae family, western redcedar (Thuja plicata Donn ex D. Don) and Lawson's cypress [Chamaecyparis lawsoniana (A. Murray) Parl.], in comparison with the native Scots pine (Pinus sylvestris L.) in the northeast part of the Czech Republic. The constructed tree ring chronologies were used as a basis for dendroclimatological analyses: basal area increment (BAI), linear growth trends, Pearson's correlations between climate variables and growth, resilience indices and others. Among the analysed species, Thuja plicata revealed the highest BAI and the most positive growth trend in the last 35 years, with values 2–3 times higher. The Chamaecyparis lawsoniana exhibited the highest negative correlation with mean summer temperatures. In general, Pinus sylvestris showed the highest correlations with precipitation. No clear pattern in resilience indices has been observed. Among the two introduced tree species examined, Thuja plicata emerges as a particularly promising candidate for future application in Central European conditions under ongoing GCC. |
Influence of the amount of water on the growth of one species and four hybrids of Paulownia in the first year of cultivation in Central EuropeOriginal PaperJiøí Kadlec, Kateøina Novosadová, Martin Kománek, Radek PokornýJ. For. Sci., 2025, 71(6):286-296 | DOI: 10.17221/19/2025-JFS
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Understanding societal priorities for forest ecosystem services: Survey insights from 'Forestry Days 2024' in SlovakiaOriginal PaperZuzana Sarva¹ová, Jozef Pajtík, Zuzana Dob¹inskáJ. For. Sci., 2025, 71(4):195-204 | DOI: 10.17221/7/2025-JFS Understanding society's demand for forest ecosystem services (FES) is crucial for effective forest management and the development of supportive instruments, such as payments for ecosystem services (PES). This study surveyed visitors at 'Forestry Days 2024' in Slovakia through face-to-face questionnaires, capturing their views on FES and necessary management changes. Results show that regulating services and biodiversity are prioritised over cultural and provisioning FES. Respondents indicated a clear need for changes in forest management to reflect their FES preferences. Notably, perceptions of specific FES varied by gender, age, forestry background, and forest ownership but not by residence type. Public PES were considered the most acceptable policy for enhancing FES management, providing valuable insight for aligning public preferences with sustainable practices in Slovakia. |
Additive volume-equation systems for Pinus ayacahuite and Pinus douglasiana in temperate forests of the Sierra Norte, Oaxaca, MexicoOriginal PaperWenceslao Santiago-García, Jonathan Ramírez-Arce, Agustín Ramírez-Martínez, Adan Nava-Nava, Juan Carlos Guzmán-Santiago, Elías Santiago-GarcíaJ. For. Sci., 2025, 71(9):441-455 | DOI: 10.17221/49/2025-JFS Volume models are essential tools for quantifying timber stocks and optimising forest utilisation. This study aimed to develop additive volume systems based on one- and two-entry simultaneous equations for Pinus ayacahuite Ehrenb. ex Schltdl. and Pinus douglasiana Martínez. Destructive sampling of 55 P. ayacahuite trees and 65 P. douglasiana trees was conducted in the communal forest of Ixtlán de Juárez, Oaxaca, southern Mexico. The additive systems were fitted using non-linear seemingly unrelated regression to estimate tree-volume components: stem and branch volumes, with whole-tree volume being the sum of both. The systems were evaluated using the relative ranking method, considering statistical indicators of accuracy, variability, and relative errors. Additionally, the predictive capacity of the equations was assessed through linear regression between observed and predicted values for each volume component, and the biological consistency was verified. The results indicate that two-entry additive systems provide greater accuracy in estimating stem, branch, and whole-tree volumes for both species. These equations are based on the Schumacher-Hall model, and their recommended range of application for both species is for diameter at breast height (DBH) between 9 cm and 75 cm, and for total height (H) between 9 m and 34 m. Therefore, their application is recommended for forest inventories and the planning of sustainable forest management. |
Assessment of aboveground biomass and carbon stock of subtropical pine forest of PakistanOriginal PaperNizar Ali, Muhammad Saad, Anwar Ali, Naveed Ahmad, Ishfaq Ahmad Khan, Habib Ullah, Areeba Binte ImranJ. For. Sci., 2023, 69(7):287-304 | DOI: 10.17221/125/2022-JFS The presented study estimated the aboveground biomass (AGB) of Pinus roxburghii (chir pine) natural forests and plantations, and created biomass maps using a relationship (regression model) between AGB and Sentinel-2 spectral indices. The mean AGB and BGB (belowground biomass) of natural forests were 79.54 Mg·ha–1 and 20.68 Mg·ha–1, respectively, whereas the mean AGB and BGB of plantations were 94.48 Mg·ha–1 and 24.56 Mg·ha–1, respectively. Correlation showed that mean diameter at breast height (DBH) and mean height have weak relationships with AGB, and BGB has shown correlation coefficients (R2 = 0.46) and (R2 = 0.56) for polynomial models. Regression models between AGB (Mg·ha–1) of Pinus roxburghii natural forest and Sentinel-2 spectral indices showed a strong relationship with Ratio Vegetation Index (RVI) with R2 = 0.72 followed by Normalized Difference Vegetation Index (NDVI) and Atmospherically Resistant Vegetation Index (ARVI) with R2 = 0.70. In contrast, the lower performance of spectral indices has been shown in regression with plantation AGB. Correlation coefficients (R2) were 0.41, 0.41, and 0.40 for RVI, NDVI, and ARVI, respectively. All indices showed that the distribution of AGB data was not the best fit with the linear regression model. Therefore, non-linear exponential and power models were considered the best fit for NDVI, RVI, and ARVI. A biomass map was developed from RVI for both natural forests and plantation because RVI has the highest R2 and lowest P-value. |
Silver fir restitution: The role of seedling stock type in adapting to various environmental conditionsOriginal PaperWojciech Kowalkowski, Rados³aw Jagie³³o, Marlena Baranowska, Wladys³aw BarzdajnJ. For. Sci., 2025, 71(7):358-371 | DOI: 10.17221/28/2025-JFS Due to past human activities, Abies alba Mill. (European silver fir) now covers only 0.7% of the forest area in the Sudety Mountains. A large-scale restitution program has been launched to produce, plant, and effectively protect over 200 million seedlings. This study aims to validate commonly used seedling stock types and provide critical insights into identifying the most effective one. Three-year-old bareroot seedlings were produced in the open-canopy nursery (3/0) or under-canopy nurseries in Scots pine (Pinus sylvestris L.) (3/0 Sp) or Norway spruce [Picea abies (L.) H. Karst] (3/0 Ns) stands. Two stocks were produced in a greenhouse and transplanted to an open-canopy nursery (2/1) after the second year or into containers designed by Kosterkiewicz (2/1 K). Seedlings have been planted in four regions in the Sudety Mountains. Two performance characteristics have been measured: height and survival rate. Our findings demonstrate a clear gradient in sapling performance among seedling stock types (survival rate): 2/1 K (81%), 3/0 (73%), 3/0 Sp (73%), 2/1 (70%), 3/0 Ns (62%). This paper has shown that under favourable environmental conditions, bareroot seedlings can sufficiently achieve stable regeneration. Containerised seedlings perform better in harsher and more challenging microclimatic or trophic conditions. Kosterkiewicz's method presents a relatively low-cost and environmentally friendly alternative for silver fir restitution. |
The new EU Timber Regulation 2023/1115 and its legal implications for the Czech forestry and timber sectorReviewPetra Hlaváèková, Martin Cempírek, David BøezinaJ. For. Sci., 2025, 71(12):575-588 | DOI: 10.17221/82/2025-JFS Regulation (EU) 2023/1115 on deforestation-free products (EUDR) establishes a substantially revised legal framework that extends beyond the previous EU Timber Regulation (EUTR 995/2010) by integrating legality, sustainability, and traceability obligations. This article provides a legal and comparative assessment of the implications of the EUDR for the Czech forestry and timber sector. The methodological approach combines doctrinal interpretation of EU legislation, comparative analysis of national implementation models, and an examination of relevant case law. Experiences from selected EU Member States are used to illustrate institutional, technological, and administrative challenges linked to EUDR implementation. The results indicate that, although the Czech Republic has an established regulatory framework under Act No. 251/2025 Coll., effective compliance with the EUDR will require improved coordination among supervisory authorities and the development of a unified digital platform for submitting and verifying due diligence declarations. Evidence from other European countries shows that integrated monitoring systems and the use of third-party certification can enhance both efficiency and transparency. The study concludes that the successful implementation of the EUDR in the Czech context will depend on institutional capacity, digital readiness, and the ability of forest managers and traders to adapt to more stringent environmental and traceability requirements. |
Himalayan fir growth in central Bhutan reflects variability in temperature and precipitationOriginal PaperJiøí Lehejèek, Gabriel Vávrù, Sangay Wangchuk, Miroslav Svoboda, Katrien BoonenJ. For. Sci., 2025, 71(10):516-524 | DOI: 10.17221/58/2025-JFS 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. |
Overgrazing strongly impedes the natural regeneration of the endemic Boswellia species on Socotra IslandOriginal PaperSalem Hamdiah, Klemen Eler, Kay Van Damme, Fabio Attorre, Dario La Montagna, Michele De Sanctis, Mohammed Shaneyehen, Mohammed Amar, Theodore Danso Marfo, Petr MadìraJ. For. Sci., 2024, 70(5):249-263 | DOI: 10.17221/3/2024-JFS Frankincense trees (Boswellia spp.) worldwide are affected by a number of threats, including global warming and changing land management practices. On the Socotra Archipelago (Yemen), which harbours eleven endemic Boswellia species, grazing is generally assumed to be one of the main threats preventing natural regeneration. To test the impact of overgrazing on natural regeneration, we established an in situ experiment on four different Boswellia taxa in different areas of Socotra Island. Mortality and the height increment of seedlings were measured for a period of two/three years in five plots excluded from grazing (fenced) and in five paired control (unfenced) plots. Each plot was 50 m × 50 m in size and contained several adult trees as a source of viable seeds. Our results show that seedling mortality was significantly higher, and seedling height increment generally (4 out of 5 sites) lower in open compared to fenced plots. In the fenced plots, the number of seedlings for all species reached up to 772, with 560 surviving seedlings. In comparison, the control plots reached up to 296 seedlings, with 176 seedlings surviving after 2–3 years. The results of our experimental study indicate that grazing directly threatens the natural regeneration of the endemic Boswellia on Socotra Island. However, seedling mortality remained relatively high inside the exclosures as well, which indicates that even without the pressure of livestock grazing, other impacts remain a challenge for the future conservation of the archipelago's unique frankincense trees. |
Age-related phenological and anatomical response of European beech (Fagus sylvatica L.) under severe summer drought conditionsOriginal PaperDimitrios Tsalagkas, Hanu¹ Vavrèík, Vladimír Gryc, Kyriaki GiagliJ. For. Sci., 2024, 70(9):458-475 | DOI: 10.17221/16/2024-JFS The year 2018 was distinguished by a warm summer with extended periods of low or no precipitation. In this context, we investigated the intra-annual dynamics of xylem differentiation phases and quantitative vessel anatomy to analyse the age effect on the xylem formation response of younger (50 years) and older (135 years) mature European beech trees under summer drought conditions. The xylem formation dynamics of young and old trees were performed on microcores collected at weekly intervals in the Rájec-Nìmèice ecological station in the South Moravia region (Czech Republic). The onset of xylem formation was found identical in both age trees, and most of the trees ceased their enlargement by the end of July, which is attributed to the harsh environmental conditions of this month. Young trees were characterised by a 10-day extended enlargement period and a higher growth rate, resulting in more vessels and a wider tree-ring width. No significant linkage was found between intra-annual environmental conditions of the 2018 year or age effect and the vessel anatomy traits. |
Hydrology and carbon pool characteristics regulate dissolved carbon export in a subtropical forest headwater streamOriginal PaperZemin Zhao, Fuzhong Wu, Yan Peng, Qiqian Wu, Qiao Yang, Chaoxiang Yuan, Xiangyin Ni, Kai YueJ. For. Sci., 2026, 72(4):188-201 | DOI: 10.17221/68/2025-JFS
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The role of the water regime in a reclaimed limestone quarryOriginal PaperMarcela Burnog, Ale¹ KuèeraJ. For. Sci., 2024, 70(8):391-406 | DOI: 10.17221/6/2024-JFS This study focused on the hydrophysical characteristics of an abandoned limestone quarry in Czechia. Six sites were examined; two sites were undergoing natural succession (the Quarry Wall and Reed Canary Grass plots, which had undeveloped arboreal layers) and four sites were undergoing managed forest reclamation. Of the four forest reclamation sites, three were classified as prospering (the Prospering Lime, Prospering Maple and Prospering Lime + Oatgrass plots) and one was in decline (the Declining Larch + Lime plot). The arboreal layer included small-leaved lime (Tilia cordata Mill.), sycamore maple (Acer pseudoplatanus L.), and European larch (Larix decidua Mill.). Our results showed that Lime + Oatgrass plot retained more water than other plots. Field soil moisture measurements indicated that throughout the 1096-day monitoring period, only the soils at the successional sites reached the wilting point (Quarry Wall plot: 159 days; Reed Canary Grass plot: 43 days). Soil heterogeneity in the reclaimed areas was due to variation in the soil profile depth, disturbance from mining activities, reclamation efforts, and the availability of quality soil material. Soil conditions and the dynamics at the quarry created less than ideal conditions for tree regeneration. This primarily relates to limiting and significantly heterogeneous successional plots. |
Sap flow modelling based on global radiation and canopy parameters derived from a digital surface modelOriginal PaperTomá¹ Mikita, Zdenìk Patoèka, Elizaveta AvoianiJ. For. Sci., 2023, 69(8):348-359 | DOI: 10.17221/191/2022-JFS Sap flow represents water transport from roots to leaves through the xylem and is used to describe tree transpiration. This paper proposed and tested a procedure to estimate sap flow by calculating global radiation in a digital model of the tree canopy surface obtained by unmanned aerial vehicle imaging. The sap flow of nine trees was continuously measured in the field. In the digital surface model, individual canopies were automatically delineated, their parameters were determined and the global radiation incident on their surface on specific days was calculated. A polynomial relationship was found between sap flow and the calculated incident solar radiation during the morning hours with a coefficient of determination of 0.98, as well as a linear relationship between the decrease in radiation and sap flow during the afternoon with a correlation coefficient of 0.99. Using the Random Forest machine learning method, a model predicting the sap flow of the trees was created based on the global radiation and canopy parameters determined from the digital surface model of tree canopies. The resulting model was deployed on additional days and compared to field measurements of sap flow, achieving a correlation coefficient of 0.918. In addition, two linear regression models were created for a tree group, achieving coefficients of determination of 0.66 and 0.90. |
Analysis of selected functional parameters of saw chainsOriginal PaperPavel Nevrkla, Lubo¹ Stanìk, Jindøich NerudaJ. For. Sci., 2025, 71(2):72-85 | DOI: 10.17221/64/2024-JFS Results obtained from the research study focused on the functional parameters of five saw chains tested on a test bench equipped with an electrically driven chain saw brought a number of findings. One of the most important of them is the significant difference between the cutting rates of round and square chains. The cutting rate of square chains R = 27.9 cm2·s–1 is about 12% higher than the cutting rate of round chains. The influence of the chain construction on the chain cutting rate was conclusively demonstrated – the cutting rate of chains with a square profile is higher than the cutting rate of round-profile chains. It was further found out that although the specific energy Em = 77.8 Ws·cm–2 is by ca. 7% lower in the square chain than in the round chain, Student's t-test did not reveal any statistically significant difference in the data on the specific energy consumption of round and square chains, i.e. the influence of the chain design on the specific energy consumption of the chain at cutting was not clearly demonstrated. Other findings, for example, showed that working with a loose saw chain on the guide bar impairs parameters of the chain operation or that energy demands of cutting with the saw chain are directly proportional to wood density (hardness) and increase with the decreasing wood moisture. Yet another finding was learning the energy flow structure, which indicated that 46% of total power input is consumed by the electric motor alone for its operation while only about 7% goes for driving the chain movement along the bar (without cutting) and power input required for cutting is approximately 46%. |
Hydrological risks of clear-cuts after the bark beetle outbreaks and related forest management decisions in Central EuropeReviewVít ©rámek, Kateøina Neudertová Hellebrandová, Vìra FadrhonsováJ. For. Sci., 2026, 72(4):161-173 | DOI: 10.17221/19/2026-JFS
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Boulders as functional microrefugia: Quantifying a continental-like microclimate supporting Pinus cembra at its oceanic range marginOriginal PaperYann Fragnière, Stéphanie Morelon, Alain Müller, Gregor KozlowskiJ. For. Sci., 2026, 72(2):82-92 | DOI: 10.17221/8/2026-JFS
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Applying the European Union (EU) assessment initiative of forest sustainability in Africa: A case study of the timber harvesting impact on the environment in Sierra LeoneOriginal PaperPetra Hlaváèková, Sheku Kemoh Mansaray, Samuel Antwi Darkwah, Iva ®ivìlováJ. For. Sci., 2024, 70(2):79-90 | DOI: 10.17221/74/2023-JFS The European Union (EU) provides both financial and expert support for sustainable forest management initiatives and also boosts compliance with such initiatives in Africa. Thus, there is a need to monitor the progress of implementing such initiatives. The objective of this paper is to describe the role of timber harvesting entities in environmental impact discussions, and to also identify the role of EU institutions in promoting forest sustainability in Sierra Leone. Data were collected in a controlled survey from four communities, using a questionnaire formulated according to guidelines recommended by Babbie and Mouton (2010). The reliability test shows a 0.68 internal consistency among the latent variables (Cronbach alpha test). The selected four communities were Bambawo, Dia, Basara, and Menima, with a population of 6 000, 5 400, 7 500, and 5 600 inhabitants, respectively (Stats SL 2021). A Confirmatory Factor Assessment (CFA) was used for a descriptive statistical analysis of the data. The results showed that the environmental impact has an eigenvalue of 1.08, where only variables with a factor loading exceeding 0.5 were used. The paper concludes with discussions and relevant recommendations on mitigating the impacts of timber harvesting on the environment within the study area. |
Biomechanical optimisation strategy for selecting native shrubs and herbaceous plants with superior soil and water conservation properties in combating land degradation in central-western Inner MongoliaOriginal PaperRile Ge, Wei Zhao, Hui Zhi, Yahui Lu, Shuaixin WeiJ. For. Sci., 2026, 72(1):42-55 | DOI: 10.17221/95/2025-JFS
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Public communication in forestry: A focus on church property owners and entities in the Czech RepublicOriginal PaperKateøina Holu¹ová, Jana Stachová, Eva Abramuszkinová Pavlíková, Pavel Fic, Otakar Holu¹aJ. For. Sci., 2026, 72(5):256-268 | DOI: 10.17221/34/2026-JFS
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Synergism of plant microbe interactions for remediation of potentially toxic elementsReviewRanjna Kaundal, Vipin Parkash, Supriti Paul, Meghna ThapaJ. For. Sci., 2023, 69(4):127-143 | DOI: 10.17221/1/2023-JFS
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Comparison of the growth of the provenances of silver fir (Abies alba Mill.) on research plots in the regions Novohradské hory and Èeskomoravská vrchovina at the age of 50 yearsOriginal PaperJiøí Èáp, Martin Fulín, Franti¹ek Beran, Jaroslav Dostál, Martina KomárkováJ. For. Sci., 2024, 70(1):14-23 | DOI: 10.17221/113/2023-JFS The study evaluates the results of a long-term research trial lasting 50 years in two research plots established in the 1970s aimed at solving the decline of the silver fir in the Czech Republic. A total of 103 different provenances occurring naturally across 12 countries were planted in research plots No. 67, Èernovice (Èeskomoravská vrchovina), and No. 77, Nové Hrady (Novohradské hory). The total tree height, diameter at breast height (DBH) and assessment of the health status of all trees in the area were measured with the same methodology. Subsequently, the volume of large wood was calculated by the volume equation, and the growing stock per hectare was recalculated. Based on our analysis of average height growth, it was found that trees with the best growth came from provenances that included the Czech provenances CZ 70 – ®dírec nad Doubravou, CZ 82 – Vizovice, CZ 42 – Lukov, CZ 76 – Nýrsko, Suchý Kámen, and CZ 53 – Opoèno. The last three mentioned provenances also dominated in other growth parameters (DBH and volume of large wood). Of the foreign provenances, D 146 – Schwarzwald mit Baar, S 9 – Kriváò, and S 6 – Èierny Váh produced trees that showed above-average values. The smallest growth in height was found in the trees from the provenances BG 132 – Rila, Borovets, F 104 – Departement de µ Aude, I 228 – Vallombrosa, A 93 – Wörschachwald. Although some trees of Italian provenance achieve above-average volume, due to high mortality, they are not suitable for economic use in the forests of the Czech Republic. Based on the European zoning for forests, the units from the Central European region (3.11.0 – Èeské Polabí, 3.32.0 – Schwarzwald with foothills and Baar, and 9.14.0 – Southern Apennine Mountains) were the best rated in all parameters. Specimens from 9.12.0 – Mountain forest of the northern Apennines, and 4.05.0 – Vosges showed the lowest parameters. |
Soil temperature and weather factors as key drivers of flowering phenology and nectar production in black locust (Robinia pseudoacacia L.) in HungaryOriginal PaperAlexandra Porcsin, Tamás Ábri, Helga Déri, Edit Zajácz, Bence Bolla, Katalin Szakálosné Mátyás, Károly Rédei, Zsolt KeserûJ. For. Sci., 2026, 72(4):202-211 | DOI: 10.17221/6/2026-JFS
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Sensitivity analysis and performance evaluation of neural networks for predicting forest stand volume – A case study: District 2, Kacha, Guilan province, IranOriginal PaperSima Lotfi Asl, Iraj Hassanzad Navroodi, Aman Mohammad KaltehJ. For. Sci., 2024, 70(5):209-222 | DOI: 10.17221/111/2023-JFS Tree volume is a characteristic used in many cases, such as determining fertility, habitat quality, growth size, allowable harvesting, and the principles of forest trade. It is imperative to develop methods that predict forest stand volume to obtain this extensive information quickly and cost-effectively. This study used supervised self-organising map (SSOM), multi-layer perceptron (MLP), and radial basis function (RBF) neural networks to predict forest stand volume based on physiography, topography, soil, and human factors. A sensitivity analysis method called the importance of prediction was used to determine how input variables influenced network output. First, the map of homogeneous units was prepared with ArcMap (Version 10.3.1, 2015) by combining digital layers to measure the tree's volume per hectare. Then, separate tree species in different diameter classes were measured in a circular grid of 200 m × 150 m, 0.1 ha of coverage, 3.3% sampling intensity, and a diameter at breast height (DBH) greater than 7.5 cm using systematic sampling on a homogeneous unit map in a regular random method. The neural network modelling results showed that SSOM, MLP, and RBF predicted forest stand volume most accurately according to physiography, topography, soil, and human factors. Furthermore, the sensitivity analysis results found that altitude above sea level, soil depth, and slope are the most influential input variables. In contrast, soil texture variables are the least effective at predicting forest stand volume. |
Research on an effective artificial regeneration method for selected commercially important coniferous tree species on a large sanitation cut site situated in the Javorníky Mts., Western CarpathiansOriginal PaperMartin Belko, Anna Tuèeková, Roman Longauer, Valéria Longauerová, Vladimír Maèejovský, Ivan HorvátJ. For. Sci., 2024, 70(7):353-367 | DOI: 10.17221/1/2024-JFS In response to the decline of Central European spruce monocultures driven by various factors, the Demonstration Object of Reconstruction of Spruce Forests (DORS) was established in Husárik locality, Javorníky Mts., northwestern Slovakia. The area includes the Husárik trial site, where the applicability and efficiency of different artificial regeneration methods are studied. The trial was established on a 24-ha area cleared following the outbreak of spruce bark beetles in 2011. Its altitude is 800 m a.s.l., aspect NW, slope 30%, the soil is Ranker on the soft flysch sandstone bedrock. Our study covered 4 conifers – Norway spruce (spruce), European larch (larch), silver fir (fir), and Douglas fir (doug fir). Each species was regenerated using 4 different approaches: planting of commercial bareroot transplants (BR), planting of container transplants (CON), direct seeding (DS) and vegetative cell seeding using seed shelters (VCS). Results concerning the nine-year development of transplants and seedlings, along with the calculation of cost-efficiency, are presented. As to the species, BR and CON transplants of spruce and larch reached the best survival and height. The DS larch was the most cost-efficient method of establishment of a successfully established plantation (survival > 50%; stem height > 2/3 of the weed height; ratio of damaged individuals < 50%) with a total cost of 2 372 EUR·ha–1. On the contrary, the slow initial growth of fir and Douglas fir and their extensive damage resulted in the incomparably higher cost of establishment of their successfully established plantation, such as 4 980 EUR·ha–1 for five-years-old BR fir transplants. Our findings documented that current efforts related to the restoration of salvage-felled clearings remained difficult, especially in the case of introduction or reestablishment of coniferous tree species more vulnerable to open site conditions. |
