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Results 121 to 150 of 525:

Pathogenicity of the entomopathogenic fungi against Myllocerus fotedari Ahmad, 1974 (Coleoptera: Curculionidae) under laboratory conditions in IndiaOriginal Paper

Shaziya Gull, Ahmad Tariq, Abdul Lateef Khanday, Sureshan Pavittu Meethal, Gowhar Rashid

J. For. Sci., 2023, 69(7):277-286 | DOI: 10.17221/10/2023-JFS

The weevil, Myllocerus fotedari Ahmad, 1974 (Coleoptera: Curculionidae) is widely recognised as one of the major walnut pests. Fungal pathogens have shown great potential for the management of some pest species. In the present study, the efficacy of three entomopathogenic fungi, namely Beauveria bassiana (Balsamo) Vuillemin, Metarhizium anisopliae sensu lato (Metchnikoff) Sorokin and Lecanicillium lecanii (Zimmerman) Zare and Gams were evaluated against the weevil, M. fotedari, under laboratory conditions. Each fungal suspension contained 1.0 × 109 spores of fungi in 1 mL. The experiment comprised of five treatments along with control (distilled water) and three replicates. An insecticide – chloropyrifos 20% emulsifiable concentrate (EC), was also used as positive control in the experiment. The experimental results revealed that the weevil, M. fotedari, showed mortality due to both virulence of entomopathogens and insecticide. The mortality caused by fungi varied from two days after treatment to eight days after treatment. However, the highest mortality of 100% was recorded for B. bassiana, followed by 85.1% for M. anisopliae after eight days of treatment. The efficacy of L. lecani was the lowest, leading to only 51.8% mortality, and was found significantly less virulent compared to the other two used entomopathogens. The present study is an attempt to use entomopathogens to control M. fotedari over conventional chemical insecticides.

Site classification vs. wood production: a case study based on Silver fir growth dynamics in the Western Carpathians

M. Boıeµa, R. Petráı, İ. İmelko

J. For. Sci., 2011, 57(10):409-421 | DOI: 10.17221/34/2011-JFS

We analysed wood production on an example of Silver fir growth ability within site units defined in the site classification that is currently used in the Western Carpathians. It has arisen as a very important issue, since the site units have been widely used in forestry practice and, moreover, it represents one of the input variables of growth model. Research plots established for development of a yield model for Silver fir in the sixties were used. The Korf growth equation was used to model the Silver fir growth, since it showed the best fit to the data compared to other equations. The test of residual variance of the growth models and the test of regression coefficients of the growth models were employed to investigate the differences in top-height growth of Silver fir occurring on different sites. Results showed a very high variability of the top height development within the site units. Nevertheless, two main groups of sites being different from each other were recognized. But, significant differences in the height growth of fir between site units were found mainly in mature stands starting at the age of 60, which could be due to different soil depth and nutrient regime. Lastly, discussions about the approaches to site classifications all over the world showed many alternatives used to develop a classification scheme with different and in many cases unknown precision, and thus there is a need for the objectivity of classification.


Distribution and environmental impact of alien woody species in lowland riparian forest habitats: Case study in the protected areas of Georgia, South CaucasusOriginal Paper

Giorgi Kavtaradze, Lado Basilidze, Jan Pergl, Elizaveta Avoiani, Petr Vahalik, Besarion Aptsiauri, Nani Goginashvili, Margalita Bachilava, Zurab Manvelidze, Nato Kobakhidze (email: n.

J. For. Sci., 2023, 69(9):401-414 | DOI: 10.17221/3/2023-JFS


Biological invasions are globally recognised as a significant threat to native biodiversity, as they can change the structure, composition, and functioning of the native ecological system. The riparian forest is considered a habitat highly invaded by invasive plants since rivers serve as corridors for alien species through the terrestrial ecosystem or may simply harbour exotic species that cannot survive elsewhere. The riparian forest, as a high conservation value forest, is an important part of the lowland forests of Georgia. These forests are distributed along large rivers, including the Mtkvari, Alazani, Iori, Aragvi, Ksani, Algeti, and Great and Little Liakhvi rivers. Here, we present a case study that was part of the scientific project titled 'Survey of Potential Invasive Alien Woody Species (PIAWS) in the Protected Areas of Georgia'. Protected areas (PAs) in Georgia play an important role in conserving native biodiversity, including forest ecosystems of distinguished biodiversity. We focused on the lowland riparian forest (LRF) distributed along the Mtkvari and Iori rivers within two PAs – Korugi and Gardabani Managed Reserves (MRs). Six main alien woody species (AWS) were identified in the study areas: Robinia pseudoacacia, Gleditsia triacanthos, Ailanthus altissima, Acer negundo, Amorpha fruticose and Morus alba. Among these AWS, the local status of R. pseudoacacia, G. triacanthos, A. altissima, and A. fruticosa is invasive, while that of A. negundo and M. alba is naturalised. The environmental impact of AWS on LRF habitat was evaluated using the Environmental Impact Classification for Alien Taxa (EICAT) classification system. A major or moderate impact of AWS on the LRF habitat is evident, which, according to EICAT impact mechanisms, is expressed as apparent competition and physical, structural and indirect impacts. The study revealed that the impact levels of three AWS, R. pseudoacacia, G. triacanthos, and A. altissima, were classified as major or moderate ('harmful' impact), while the remaining AWS, A. negundo and A. fruticosa, were of minor or minimal concern. AWS in the invaded areas of the LRF are found as an understorey layer or, otherwise, they have already formed the main canopy and replaced native dominant woody species. Therefore, undesirable structural and succession processes in invaded LRFs are evident.

Provenance affects the growth and mortality of teak (Tectona grandis L.f.) plantations cultivated in central NicaraguaOriginal Paper

Jakub Èernŭ, Peter Haninec, Kateĝina Novosadová, Zdenìk Patoèka, Pavel Haninec, Petr Madìra

J. For. Sci., 2023, 69(1):1-10 | DOI: 10.17221/115/2022-JFS


Teak has been planted extensively by smallholders in Central America within reforestation programmes and has become one of the most valuable timbers. The five-year growth and mortality of teak cultivated in a plantation in central Nicaragua, representing sites at the low limit of teak ecological valence, were evaluated. From 2006 to 2010, 72 pure teak stands were established, with 48.93 ha in total. For afforestation, planting stock from five provenances was used and planted at 1 m × 1 m spacing to stimulate the height growth and reduce broad crowns formed by self-pruning. In the pure teak stands, 144 permanent sample plots of 0.01 ha in size were established in 2011. From 2011 until 2015, the tree height and stem girth of all individuals in the studied sample plots were measured, and mortality based on the stand density was assessed. Significant differences between the provenances were observed. The highest growth was noted in the Local provenance originated from the studied area, whereas the Semilla provenance from Costa Rica, characterised by the lowest growth ability, was characterized by lower radial increment and mean tree height with high mortality.

Potential of mixed Picea abies (L.) Karst. and Pinus sylvestris L. forests in lowland areas of Central BohemiaOriginal Paper

Pavel Brabec, Jakub Brichta, Zdenìk Vacek, Stanislav Vacek, Václav İimùnek, Vojtìch Hájek

J. For. Sci., 2023, 69(11):470-484 | DOI: 10.17221/76/2023-JFS

Mixed forests play a key role in terms of stability, production potential, and adaptation to climate change. In addition, the studied Norway spruce [Picea abies (L.) Karst.] and Scots pine (Pinus sylvestris L.) belong to the most economically important tree species in Europe. The objectives were to determine the effect of the species composition of these two tree genera on the production, structure, diversity, and growth of mixed stands at lower elevations in the Czech Republic. Based on dendroecological samples, research was also carried out on the influence of climatic factors and climate change on the radial growth of these trees of interest. Mixed forests showed higher timber production by 29.8% compared to spruce and pine monocultures. The production of mature stands ranged from 328 to 479 m3·ha–1. Spruce achieved higher radial growth, but its growth variability was higher than that of pine. Compared to precipitation, temperatures had a greater influence on the radial growth of both tree species, especially in the growing season. In terms of diversity, mixed stands achieved significantly higher structural differentiation and overall diversity compared to monospecific variants. Mixed stands can achieve higher production potential, diversity, and especially resistance to climatic extremes in the lowland regions of the Czech Republic. The differences between mixed stands and monocultures, i.e. the effect of tree species mixing, depend on the appropriate proportions of tree species and their spatial pattern.

Comparison of the approach to determination of the rotation period of forest stands in the Czech Republic and in the Slovak RepublicOriginal Paper

Michaela Korená Hillayová, Kateĝina Holuıová, Klára Báliková, Ján Holécy

J. For. Sci., 2022, 68(10):413-422 | DOI: 10.17221/107/2022-JFS

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.

Sap flow modelling based on global radiation and canopy parameters derived from a digital surface modelOriginal Paper

Tomáı Mikita, Zdenìk Patoèka, Elizaveta Avoiani

J. 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.

City longhorn beetle (Aeolesthes sarta): A review of the species, its distribution, ecology, damage, prevention and controlReview

Umer Hayat

J. For. Sci., 2022, 68(6):199-212 | DOI: 10.17221/34/2022-JFS

The city longhorn beetle (Aeolesthes sarta) (CLB) (Coleoptera - Cerambycidae) is a polyphagous invasive pest of both healthy and suppressed broadleaved trees in central Asia. CLB causes a great degree of damage in the countries of its origin. To understand this pest in a better way, a detailed review study has been conducted to gather all the valuable information related to the CLB. This review study covers the main aspects of the CLB, its morphology, ecology, distribution, damage, and control measures. The life span of the CLB is two years. It is mainly distributed in the central Asian countries and preferably damages broadleaved tree species, especially Juglans regia, Populus alba, P. euphratica, Acer spp, Salix alba, S. babylonica, Malus pumila, M. sylvestris, Platanus orientalis and Ulmus spp. Effective control and management practices include cutting, removing + burning of infested trees, cultivating high resilient tree species, use of biocontrol agents (i.e. fungus), and use of aluminium phosphide as a pesticide to significantly help control the CLB population. A CLB invasion in a new favourable habitat could impose a serious threat to broadleaf forests and plantations. Therefore, the keen monitoring and surveying of woodland management techniques are recommended. The strict monitoring and inspection of traded wood material at airports and seaports are highly recommended. There is a need to conduct multiple research studies to profoundly understand the CLB phenology, ecology, transportation mode, and damage severity to bridge the gap.

Acacia canopy structure and carbon stock in Ba Vi, VietnamOriginal Paper

Bui Manh Hung, Nguyen Thi Bich Phuong, Nguyen Van Quy, Nguyen Van Hop, Le Van Cuong, Yusif Habib

J. For. Sci., 2023, 69(1):21-32 | DOI: 10.17221/46/2022-JFS


Forest structure is a key component of its management and assessment in every forest ecosystem. In the study, 23 plots were established to obtain data on the acacia forest community based on tree size. Results from the study indicated that the acacia community could be broadly divided into two groups based on tree-size variables. The diameter and height frequency distributions of Group 1 were right-skewed, while those of Group 2 were more complicated. In both groups, there were positive correlations between tree-size variables, nonetheless the relationship between diameter at breast height and total height was best described using the cubic equation. Further, the Weibull and Sinh-Arcsinh (SHASH) best simulated the diameter and height frequency distribution. High-quality trees were found in a large diameter (> 30 cm) and height groups (> 22 m). In contrast, low-quality plants often concentrated on the smallest sizes. Therefore, trees with a diameter of 2–10 cm and a height lower than 8 m should receive attention to tend. Carbon stock in the two groups was 61.48 Mg·ha–1 and 64.21 Mg·ha–1, respectively. Tending solutions and measurements should be carried out regularly to promptly propose silvicultural measures and improve forest quality in future.

Effect of bioengineering treatments on reduction of soil erosion from road cut slope and fill slopeOriginal Paper

Aidin Parsakhoo, Seyed Ataollah Hosseini

J. For. Sci., 2023, 69(9):367-376 | DOI: 10.17221/55/2023-JFS

The efficiency of different conservation practices on soil loss from road side slopes is scarcely identified in the Hyrcanian forests of Iran, which could retard the implementation of these management practices. Sediment of 48 plots on the cut slopes and fill slopes of forest roads were collected to explore their responses to soil conservation practices, including straw bale (SB), living hedge (LH), dead hedge (DH), geo-cell (GC), geotextile (GT), and bare soil (BS). Moreover, the efficiency of conservation practices was evaluated to find a cost-effective approach. Sediment traps were installed at the toe of side slopes in the ditch and end of each treated plot. Sediment volume was measured monthly for six months. The results demonstrated that the lowest soil loss occurred in autumn and fill slopes treated with GC (5.05 g·m–2) and the highest in winter and cut slopes treated with SB (41.81 g·m–2). In all cases, soil loss from BS (126.74 g·m–2) was significantly higher than in plots treated with conservation practices. GC performed well under certain circumstances due to two-dimensional protections of contiguous wooden lumbers. Moreover, it was found that in a short time there were not any significant differences between LH (28.78 g·m–2), DH (36.01 g·m–2), and GT (30.61 g·m–2) in soil loss control ability. Regarding implementation and installation costs, GC (USD 16.67 per plot) was the most expensive, while LH (USD 3.33 per plot) was the cheapest. Regarding GC, it is necessary to conduct long-term research to determine economic efficiency, durability, maintenance, and repair costs. Until then, it is possible to use affordable treatments such as LH, which have yielded favourable results in efficiency.

Potential of Morus nigra in Central Europe focused on micropropagation: A short reviewReview

Pavel İvagr, Josef Gallo, Jan Vítámvás, Vilém Podrázskŭ, Martin Baláı

J. For. Sci., 2023, 69(11):463-469 | DOI: 10.17221/73/2023-JFS

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.

Norway spruce in forest ecosystems of the Czech Republic in relation to different forest site conditions

V. Mansfeld

J. For. Sci., 2011, 57(11):514-522 | DOI: 10.17221/14/2011-JFS

The paper analyses the representation of Norway spruce (Picea abies [L.] Karst.) (hereinafter spruce) in relation to different conditions of forest sites. The analysis is based on data from the National Forest Inventory conducted in the Czech Republic in 2001-2004 (hereinafter NFI), stratified according to units of the Forest Site Classification System (Plíva 1971, 2000). Results of the analysis provide a structured image of the current share of spruce. The formerly published information on the natural share of spruce was corroborated and the recommended share of spruce in the target species composition of the spruce management system was analyzed. The analysis documents the applicability of NFI data in the technical discussion concerning the future form of forest ecosystems in the Czech Republic. The results can be used as the groundwork for concrete forest management decision-making and will contribute to the study of the biological diversity of forest ecosystems.

Forest fire area detection using Sentinel-2 data: Case of the Beni Salah national forest ‒ AlgeriaOriginal Paper

Rabah Zennir, Boubaker Khallef

J. For. Sci., 2023, 69(1):33-40 | DOI: 10.17221/50/2022-JFS



Forest cover plays an important role in terms of biodiversity and the environment. The Beni Salah national forest in its part which is located in the Guelma province in the extreme northeast of Algeria is an illustrative example where forest fires represent the chronic phenomenon which weighs heavily on this forest. The present study comes after a forest fire that occurred in 2021, when 3 000 ha of this forest were ravaged by forest fires according to the conservation of forests of Guelma. The main objective of this research is to map the severity of burns and estimate the severely burned area using Sentinel-2 satellite images based on remote sensing indices such as Normalized Difference Vegetation Index (NDVI), Differenced Normalized Difference Vegetation Index (dNDVI), Normalized Burn Ratio (NBR), Differenced Normalized Burn Ratio (dNBR), Green Normalized Difference Vegetation Index (GNDVI), Differenced Green Normalized Difference Vegetation Index (dGNDVI), Burn Area Index (BAI) and Relativized Burn Ratio (RBR). The result obtained revealed that 28.23% of the study area represents a seriously burned area. The established burn severity map is a real decision-making tool, but it still has certain limitations.


Analysis of the propensity of Italian and German forest owners towards forest certification for ecosystem servicesOriginal Paper

Emanuela Lombardo

J. For. Sci., 2023, 69(6):266-276 | DOI: 10.17221/193/2022-JFS

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.

Estimation of Fagus orientalis Lipsky height using nonlinear models in Hyrcanian forests, IranOriginal Paper

Mohammad Rasoul Nazari Sendi, Iraj Hassanzad Navroodi, Aman Mohammad Kalteh

J. For. Sci., 2023, 69(10):415-426 | DOI: 10.17221/93/2022-JFS

Tree height is one of the most important variables in describing forest stand structure. However, due to difficulty in height measurement, especially in dense and mountainous forests, the common approach is to invoke the height-diameter (H-D) models. The oriental beech (Fagus orientalis Lipsky) is one of the most important species of Hyrcanian forests, over the mid to high-altitudes (400–1 800 m a.s.l.), in northern Iran. In this study, the H-D relationship of beech trees was investigated separately for mid-altitude and high-altitude in Shafaroud forests of Guilan using 14 nonlinear H-D models and an artificial neural network model (ANN). To collect data, a systematic random sampling method within a 100 × 100 m regular randomized grid was applied. In total, 3 243 individual trees in 255 circular plots with 0.1 ha were measured. For comparing the results, performance criteria including root mean square error (RMSE), R2adj, Akaike's information criterion (AIC), and mean absolute error (MAE) were used. In high and mid altitudes, Meyer (1940) and Bates and Watts (1980) models had the best performance, while Watts (1983) model and Burkhart-Strub (1974) model had the worst performance in high-altitude and in mid-altitude, respectively. On the other hand, the ANN model had the best accuracy and performance in both sites. Since the performance of the ANN model is superior and consistent compared to the common nonlinear models, here it is preferred for both regions.

Households' willingness to pay for forest conservation in Ethiopia: A reviewReview

Diriba Abdeta

J. For. Sci., 2022, 68(11):437-451 | DOI: 10.17221/94/2022-JFS

Environmental valuation studies in the context of developing countries have become more frequent in recent years. However, literature which reviews and examines the environmental valuation studies is limited. Thus, this paper performed a literature review on forest contingent valuation studies conducted in the Ethiopian context in the past two decades (2000 to May 2022), focusing on two specific objectives: (i) to examine amounts of resources that households are willing to pay (WTP) for forest conservation, and (ii) to identify determinants of households' WTP. Results indicate the mean lower annual WTP of USD 0.41 (2.63 birr) and 7.04 man-days per household in money and labour time, respectively. Whereas the mean upper annual WTP of USD 53.52 per household in monetary payment and 94.34 man-days per household in labour time contribution are found for the management and conservation of forest in Ethiopia. The finding reveals that there is a limited proportion of the examined studies that included and estimated WTP in a non-monetary payment vehicle, implying a need for future researches on the topic. The result shows that demographic and socio-economic variables, physical assets ownership, institutional and infrastructural services and bid price variables were the main determinants of households' WTP. This suggests that the forest conservation intervention program involving public participation in the country needs to consider the identified determinants of WTP in design and implementation of the program. Moreover, the finding indicates the presence of mixed results on the effect and direction in which some determinants of WTP are affected. This recommends a pressing need for comprehensive future studies on the research theme.

Use of bioreactors RITA® in the propagation of Pinus patula Schiede ex Schltdl. & Cham.Short Communication

Arturo Alonso Armas Silva, Lourdes Georgina Iglesias Andreu, Marco Antonio Ramírez Mosqueda

J. For. Sci., 2023, 69(3):124-126 | DOI: 10.17221/189/2022-JFS


The objective of the present work was to evaluate the efficacy of use of the RITA® temporary immersion system in the large-scale propagation of P. patula. The effects of four concentrations (0.00 µM, 4.50 µM, 9.00 µM, and 13.51 µM) of 6-benzylaminopurine (BAP) on 10 hypocotyl explants were studied using a completely randomised design with three replicates per treatment. Five hypocotyl explants were grown in 250 mL RITA® containers of Woody Plant Culture Medium (WPM) supplemented with 20 g·L–1 sucrose and 10 mg·L–1 vitamins from Murashige and Skoog (MS) culture medium. The frequency of immersion of the explants into the culture medium was 2 min every 8 hours. The number of adventitious buds and calli formed, as well as shoot growth, were evaluated after 6 weeks of in vitro culture. The 4.50 µM concentration of BAP was the best treatment for shoot production (5 shoots per plant) and shoot length (1.32 cm). These results could help the widespread vegetative propagation of this important forest species.

Silvicultural options to promote natural regeneration of Scots pine (Pinus sylvestris L.) in Western Ukrainian forestsOriginal Paper

Vasyl Lavnyy, Peter Spathelf, Rostyslav Kravchuk, Ruslan Vytseha, Volodymyr Yakhnytskyy

J. For. Sci., 2022, 68(8):298-310 | DOI: 10.17221/73/2022-JFS

Scots pine (Pinus sylvestris L.) forests belong to the most relevant forest types in the Western Ukrainian Roztochia area. The promotion of close-to-nature forest management in Ukraine in the framework of the forest strategy 2 035 supports natural regeneration and the application of diverse felling methods beyond clearcutting. In the present study, natural regeneration was analysed in mixed Scots pine stands on poor and relatively rich soils, after small clearcuts, shelterwood cutting and gap fellings (with or without soil preparation), with respect to tree species composition, species abundance and height growth. It could be shown that Scots pine is the most abundant species in all the felling systems, with on average more than 100 000 plants per ha on poor soils. Other admixed tree species only occur with small shares. Natural regeneration, especially of Scots pine, was less abundant on rich soils and in shelterwood, compared to a small clearcut. After the young plants have established, their abundance declined in the second and third year due to competing herbaceous plants and thick litter.

Impact of protection methods and abiotic factors on Nothofagus pumilio seedlings mortality in Torres del Paine National Park, ChileOriginal Paper

Martin Smola, Josef Cafourek, Antonín Kusbach, Martin İenfeldr, Josef Stĝíteckŭ, Petr Madìra

J. For. Sci., 2023, 69(9):389-400 | DOI: 10.17221/45/2023-JFS


National parks (NP) are the last refugia of forests dominated by the Nothofagus species in Chile. However, frequent, careless human-caused fires are destroying these forests even within the national parks. After large-scale fires, N. pumilio stands are unable to recover naturally neither in generative nor in vegetative ways and artificial regeneration must be resorted to in order to maintain their extent. However, even artificial regeneration is not successful without protection against browsing. Therefore, the aim of this study was to experimentally test a range of repellents and other methods of mechanical protection of seedlings against browsing. Five replicates of plots were placed in Torres del Paine NP, in different habitat conditions and with different methods of protection against browsing (11 repellents, wire mesh, plastic tube and control). In each plot, 12 seedlings were treated with each type of protection. In our experiment, only 8% of the seedlings were damaged by browsing, while the mortality rate was 38%. The results indicate a more significant effect of abiotic factors (mainly frost, drought or wind) on seedling mortality than browsing. In parallel, however, it is clear that, compared with the control, six of the eleven repellents used in the experiment showed a significantly positive effect. We suggest the use of plastic tubes as the best option to protect seedlings, which, in addition to providing 100% protection against browsing, are likely to provide more favourable microclimatic conditions for seedlings, similar to leaving the burned snags.

Evaluation of silver birch diameter increment model based on data of the Czech National Forest InventoryOriginal Paper

Jan Kikal, Zdenìk Adamec

J. For. Sci., 2020, 66(11):471-481 | DOI: 10.17221/161/2020-JFS

In the Czech Republic, the silver birch (Betula pendula Roth.) is considered as a pioneer and a soil preparing tree species. It occurs mainly on clearcutting areas after disturbances. The aim of this study was to fit breast height diameter increment model for birch with respect to tree age, share of birch trees and forest site type (ecological series - ES and forest vegetation zones - FVZ). We used data of both cycles of National Forest Inventory of the Czech Republic. We evaluated production potential of this species. We tested Korf and Michailoff increment models in variant of nonlinear least squares model (NLS) and nonlinear mixed effects model (NLME). Michailoff models performed better. We found seven statistically significant and practically applicable models. The greatest influence on increment of diameter at breast height have forest vegetation zone and ecological series whereas the influence of the share of birch in forest stand is smaller. The highest absolute values of diameter increment were on gleyed or enriched with water sites in the fourth forest vegetation zone.

Production potential and structural variability of pine stands in the Czech Republic: Scots pine (Pinus sylvestris L.) vs. introduced pines - case study and problem reviewOriginal Paper

Vilém Podrázskŭ, Zdenìk Vacek, Stanislav Vacek, Jan Vítámvás, Josef Gallo, Anna Prokùpková, Giuseppe D'Andrea

J. For. Sci., 2020, 66(5):197-207 | DOI: 10.17221/42/2020-JFS

Scots pine (Pinus sylvestris L.) is one of the most important tree species in Eurasia. During the past centuries, it has been extensively introduced into artificial monocultures, but is currently experiencing a number of problems related to climate change and extreme droughts. There is a large-scale disintegration of its stands and, in addition to its replacement by other native trees, it is possible to use a wide range of introduced species of the same genus. The aim of the investigation was to compare production parameters, structure and diversity of pine stands at the age of 35 years in school Arboretum of Faculty of Forestry and Wood Science in Central Bohemia (320 m a.s.l., medium rich habitats, water deficit site). Seven species of pine were compared: ponderosa pine (Pinus ponderosa Douglas ex C. Hawson), Jeffrey pine (Pinus jeffreyi Balf.), black pine (Pinus nigra J.F.Arnold), eastern white pine (Pinus strobus L.), Lodgepole pine (Pinus contorta Douglas), Macedonian pine (Pinus peuce Griseb.) and the only native Scots pine. The results showed that significantly (P < 0.001) highest height, diameter at breast height and mean stem volume were achieved in Pinus ponderosa and P. strobus stands, while these parameters were lowest in P. peuce and P. nigra. In contrast, the lowest stand volume was calculated for P. strobus (112 m3.ha-1) due to the lower stand density, while the highest production was again in P. ponderosa (430 m3.ha-1). In terms of structural variability, the highest diversity was found in P. jeffreyi and P. peuce. The introduced pine species, especially P. ponderosa, could therefore play an important role in terms of production and economic potential and even replace native P. sylvestris on suitable sites.

Effect of structure and dynamics of forests on the occurrence of Erythronium dens-canisOriginal Paper

Stanislav Vacek, Rostislav Linda, Ivo Králíèek, Karel Vanèura, Anna Prokùpková, Romana Prausová

J. For. Sci., 2020, 66(9):349-360 | DOI: 10.17221/96/2020-JFS

The paper presents the results of a study on the impact of forest stand structure and development in 1998 to 2018 on the occurrence of dog's tooth violets (Erythronium dens-canis L.) in the Medník National Nature Monument, Czech Republic. The research was carried out in mixed European hornbeam and sessile oak stands, herb-rich European beech stands and the Sázava-river Norway spruce ecotype stands. The site and stand characteristics of the following three forest stand types were compared: 1) oak-hornbeam forests, 2) herb-rich beech forests and 3) secondary spruce forests. The results showed that the ratio of sterile and fertile plants was 2.9 to 1. The occurrence of E. dens-canis was higher in older stands with differentiated structure. On the contrary, stands characterized by a higher number of trees and basal area negatively affected the population size of E. dens‑canis. Significantly, the density of E. dens-canis decreased with increasing stand density index (SDI) and increased with increasing diameter differentiation index in relation to tree neighbours (TMd). During the period of 20 years, the E. dens-canis population increased by 40.4% on permanent research plots, while the highest changes were observed on spruce plots (+92.1%) and the lowest increase was in oak-hornbeam forests (+18.0%). The highest numbers of E. dens-canis plants were found in herb-rich beech forests (1 774 plants.ha-1), lower numbers occurred in oak-hornbeam forests (784 plants.ha-1) and minimal in secondary spruce forests (51 plants.ha-1).

Road network analysis for timber transportation from a harvesting site to mills (Case study: Gorgan county - Iran)Original Paper

A. Parsakhoo, M. Mostafa

J. For. Sci., 2015, 61(12):520-525 | DOI: 10.17221/67/2015-JFS

We summarized the results of the Road Network Analysis (RNA), when the shortest path to reduce travel time in the Gorgan city public road network, in Iran, was evaluated. The main objective was to determine whether by using a GIS-based new route approach it is possible to determine the shortest path from logging site to destination (mills). The results showed that by using the concept of travel time as a measure of the importance of nodes, the shortest path from origin to destination was found. A path with minimum links and lengths as well as maximum vehicle speed is the best. This dramatically reduced the search complexity in terms of routing.

Methods for monetary valuation of ecosystem services: A scoping reviewReview

Egor Selivanov, Petra Hlaváèková

J. For. Sci., 2021, 67(11):499-511 | DOI: 10.17221/96/2021-JFS

Adequate assessment of ecosystem services is important for the development of policies and management plans related to forestry activities and the environment. Carefully identified ecosystem values can determine which options policy makers should prioritize to provide the greatest benefit. There are numerous methods used by researchers to evaluate ecosystem services. The most widely applied methods are monetary valuation methods, they are often deemed to be the most pragmatic language when it comes to communication with political and business institutions. The main goal of this review is to analyse available literature using the methodology particular to the scoping review approach in order to identify and describe valuation methods that can be applied for monetary assessment of ecosystem services. As a result of the scoping review, over 20 monetary valuation techniques (including several less common methods such as willingness to sell and Delphi method) were derived from 16 literature sources. In the process of compiling the range of different methods, a few flaws and gaps in the communication of methods were observed such as lack of consistency in the names of different methods and mixing up concepts. In addition, a few areas for future research are suggested.

Do stand structure and admixture of tree species affect Scots pine aboveground biomass production and stability on its natural site?Original Paper

Ondĝej İPULÁK, Jiĝí SOUÈEK, Jakub ÈERNŬ

J. For. Sci., 2018, 64(11):486-495 | DOI: 10.17221/117/2018-JFS

The paper analyses stand structure and production on two experimental forest stand series of mature pure and mixed Scots pine stands, growing on natural Scots pine sites in the Czech Republic. Sessile oak was the main admixed species. In mixed stands, Scots pine constituted the dominant level of the stand, admixed species grew mostly as subdominants. Admixture increased stand densities and aboveground biomass production compared to pure stands. Sessile oak with the 20-30% number share within the Scots pine stand led to an increase of the Scots pine tree dimensions and mean stem merchantable wood (DBH ≥ 7 cm) volume compared to the pure Scots pine stand of similar density. The Scots pine and sessile oak slenderness ratios increased in mixed stands compared to monocultures, however, the stand mechanical stability was not threatened.

The impact of agricultural land afforestation on air temperatures near the surfaceOriginal Paper

Jan Vopravil, Pavel Formánek, Darina Heĝmanovská, Tomáı Khel, Karel Jacko

J. For. Sci., 2022, 68(12):485-495 | DOI: 10.17221/135/2022-JFS

Many studies showed that afforestation increases carbon storage and it can have effects on physical, chemical and biological properties of soil. Afforestation can affect local and regional climate and these effects differ between tropical, temperate and boreal areas. Forests are also efficient in protecting soils against erosion and their flood mitigation functions or other benefits are described in different publications. In this study, the pattern of air temperatures (20 cm, 40 cm and 60 cm above the surface) was studied 10 years after the afforestation of agricultural land (warm, mild dry region of the Czech Republic) with a mixture of broadleaved tree species (Quercus robur L., Quercus rubra L. and Acer platanoides L.) or monospecific Pinus sylvestris L. stand. The aim of our study was to find out the pattern of air temperatures (20 cm, 40 cm and 60 cm above the surface) on two plots (one of the plots ‒ old beech trees, the other plot ‒ clearing) in a beech (Fagus sylvatica L.) forest in a mildly warm, mildly wet region of the Czech Republic. The afforestation of agriculturally used land led to air temperature cooling and to a reduction of the amplitude of maximum and minimum temperatures. The average air temperature (from April 2021 to the beginning of November 2021) decreased by 0.7-1.1 °C on the afforested plots compared with the agriculturally used plot. In the beech forest, the average temperature decreased on the plot with clearing compared with the old beech trees (from the middle of September 2021 to the middle of November 2021). Our results confirm the benefits of afforestation to climate change mitigation; buffering of extreme temperatures is important for the human thermal comfort.

Effect of selective logging on the genetic differentiation of Juglans pyriformis Liebm. populationsOriginal Paper

Celia Cecilia Acosta-Hernández, Lourdes Georgina Iglesias-Andreu, Mauricio Luna-Rodríguez, Pablo Octavio-Aguilar

J. For. Sci., 2022, 68(12):509-518 | DOI: 10.17221/131/2022-JFS

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.

State of the raw wood growing stocks and prediction of further development of cutting in the context of coniferous stands calamity in the Czech RepublicOriginal Paper

Dalibor İafaĝík, David Bĝezina, Jakub Michal, Petra Hlaváèková

J. For. Sci., 2022, 68(10):423-435 | DOI: 10.17221/76/2022-JFS

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.

Growth response of seven multipurpose tree species to climatic factors: A case study from northwestern Himalayas, IndiaOriginal Paper

Sucharita Panda, D.R. Bhardwaj, C.L. Thakur, Prashant Sharma, Dhirender Kumar

J. For. Sci., 2022, 68(3):83-95 | DOI: 10.17221/159/2021-JFS

Identification of the species for dendrochronological studies is of great relevance to understand various aspects of climate change. However, in the northwestern Himalayan region, dendroclimatological investigations are confined to conifer species, with broadleaved species being disregarded. Thus, the present study was conducted to assess the growth response of seven multipurpose tree species (MPTs), namely Bauhinia variegata, Celtis australis, Grewia optiva, Paulownia fortunei, Toona ciliata, Ulmus villosa and Melia composita to local climate variables, viz. temperature as well as rainfall (seasonal, monthly, average) and CO2 level by evaluating the climatic signal in tree ring chronologies at Solan district, India (altitude 1 250 m) in the mid-hills of the northwestern Himalayas. The results indicated that only the maximum, rainy season temperature and CO2 level varied significantly (P < 0.05) between 1991 and 2017. Only G. optiva exhibited a significant (P < 0.05) tendency toward increased growth. C. australis has a remarkable negative correlation with temperature variables, viz. average, maximum, spring season, March temperature, whereas T. ciliata exhibits a positive correlation with temperature variables, such as rainy season, average and April temperature. Similarly, winter, total and December rainfall have a profound effect on P. fortunei, while March rainfall adversely affected the growth of B. variegata. On the other hand, G. optiva demonstrated sensitivity to both temperature (February and May) and rainfall variables (winter, February and May). U. villosa recorded a positive correlation with rainfall (autumn and October rainfall) but a negative correlation with temperature variables (maximum and April temperature). Elevated CO2 levels affected only two species (G. optiva, M. composita) out of the seven selected species. Our findings will contribute to a better understanding of the climate growth relationships of investigated tree species, as a result, to more accurate projections of the effects of climate change on these MPTs and directing future studies.

State and productivity of mixed stands with silver birch and Scots pine in Ukrainian PolissyaOriginal Paper

Viktor Tkach, Maksym Rumiantsev, Volodymyr Luk'yanets, Oleksii Kobets, Iryna Obolonyk, Oksana Tarnopilska, Sergiy Musienko, Vira Bondarenko

J. For. Sci., 2022, 68(12):519-528 | DOI: 10.17221/144/2022-JFS

The aim of the study was to assess the current state of silver birch (Betula pendula Roth.) stands in Ukrainian Polissya, as well as to identify optimal composition resulting in productive and resilient mixed birch forests. It was found that in forests managed by the State Forest Resources Agency of Ukraine, birch stands grow on an area of 352 800 ha, covering 5.6% of the total area of forests in Ukraine. Within the study region of Ukrainian Polissya, birch stands cover 294 900 ha making 12.3% of the total forest area. Naturally originated birch stands were found to dominate in the study region, with 65.4% of vegetative stands and 25.2% of those grown from seeds. However, planted stands significantly prevail in terms of growing stock as compared to natural ones. In Ukrainian Polissya, silver birch trees grow as a part of mixed pine and birch forests on 632 400 ha. Our study found that mixed pine and birch stands with 80-90% of Scots pine and 20-10% of silver birch in the composition are the most productive.

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