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Crown characteristics in the beech stand damaged by ice storm in the Eastern Serbia
No full textThe paper presents the crown characteristics of beech trees damaged by the ice storm, as well as
the structural and production characteristics of the investigated stand. The stand has been defined
phytocoenologically as the mountainous beech forest (Fagetum moesiacae montanum) on
different brown soils. The stand is located in the area of Čestobrodica in Eastern Serbia, at an
altitude of about 600 m, on a slope between 11° and 15°. The age of the stand is 90 years, the
distribution of trees by diameter classes is a typical for even-aged structure. Number of trees per
hectare is 200, basal area is 23.22 m2
/ha, total volume is 322.3 m3
/ha, and the volume increment
is 4.8 m3
/ha. The mean stand diameter is 38,4 cm, while the mean diameter of dominant trees is
50.9 cm. The mean stand height is 25.3 m, and the height of the dominant tree is 27.8 m. The
secondary crown has been formed by 61.2% of the trees, with more than half of the trunk
covered by secondary branches, while 10.2% of the trees have shown drying from the top, with
thicker branches over 1 m long drying. The average crown damage is 44.4%. Average of relative
crown length is 47.6%. The results of the research on the characteristics of tree crowns indicate
that the crowns are reduced and severely damaged by ice storm
Effect of tannic acid (TA) on increasing urea-formaldehyde (UF) adhesive performance
No full textTannic acid (TA) has been widely studied in recent years as a promising component of biomaterials due to its unique properties. The aim of this study was to evaluate the potential of the use of tannic acid in formulation of urea-formaldehyde (UF) wood adhesive to determine if it is possible to obtain, a so called, bio-based and sustainable alternative to the conventional adhesive. TA-based UF (TA-UF) resins, with three different concentrations of tannic acid (1, 3, and 5%) were prepared, and adhesive properties were tested and compared with properties of pure UF. Testing of tensile shear strength showed that the addition of a higher concentration of tannic acid in UF adhesive formulation increases its adhesive and mechanical performances compared to pure UF adhesive. Based on the results, it was concluded that TA-UF resins could be successfully applied as an environmentally friendly, bio-based wood adhesive
Canopy density for tree species in an urban park
No full textForest canopy density is a major factor in evaluating forest status and is an important indicator ofpossible management interventions. Canopy density refers to the percentage of ground area coveredby the overhead canopy of trees or other vegetation. It is a measure of how closely the branches,leaves, and foliage of plants are packed together overhead. Canopy density is important in assessingthe microclimate, light availability, and overall ecosystem characteristics of forested or vegetatedareas. In this study, we intended to analyse the canopy density of the vegetation for both the coniferousand deciduous tree species within the Pionirski˙ Park. Pionirski Park, with a total area of approximately3 ha, is located in the narrowest central zone of Belgrade the capital of Serbia. The Park representsthe cultural, administrative, and commercial seat and, with its surroundings, occupies an importantplace in the urban tissue of Belgrade. As part of the entire system of public greenery, Pioneer Park isan important element of the climatic infrastructure. The area of the park consists of three spatiallydifferent sub-units. The first one with the highest quality dendrological vegetation. The second unitconsists of a flower parterre, and the third part consists of a richly arranged flower parterre withindividual trees of tall conifers and deciduous trees. The richness of the park consists of a variety ofautochthonous and non-autochthonous dendroflora. The imposing dimensions of the most valuablespecimens stand out in particular: English oak (Quercus robur L.), European hackberry (Celtis australisL.), ginkgo (Ginkgo biloba L.), horse chestnut (Aesculus hippocastanum L.). The tree species weredetermined in the field during the photograph analyses. To obtain the canopy density, hemisphericalphotographing was used in this study. Field trips have been conducted during August of 2024.Consequently, using the Plant canopy imager C-110 (CID Bio-Science) in total of 71 hemisphericalphotographs were acquired. Using a self-leveling digital camera, C-110 captures 150° field-of-viewimages of plant canopies for hemispherical photograph analysis. The imager instantly estimates theLeaf Area Index (LAI) and measures Photosynthetically Active Radiation (PAR) levels. The 24 PARsensors in the arm of the instrument calculate sunflecks, and measurements can be obtained underany sky condition. The data on the results were evaluated and discussed based on the type of treesand the area of the park in which these canopies were in. The highest value of canopy density of 73.9%was recorded for Tilia platyphillos, while the lowest value of 50.4% was recorded for Cedrus atlantica.A mean value of 64.4% and a coefficient of variation of 8.23% indicate slight variation in canopydensity. The study found that tree species and the different parts of the park do not have a statisticallysignificant influence on canopy density change. Higher canopy density indicates a more continuous,closed canopy, while lower canopy density means the canopy is more open and transparent. Urbanecanopy density assessments are foundational to understanding the amount and distribution of treecanopy cover in a community to set goals and targets to strategically increase canopy cover andprioritize the protection of existing tree canopy. Based on the results, it could be concluded that thepark is not exposed to major influences that can affect the canopy density. However, our cities oftenlack the resources to support urban tree canopy assessments as well as efforts to expand, manageand protect urban tree canopy based on the priorities of their individual communities.Alicante (Spain), 26th-29th November 202
Beech Wood Steaming – Chemical Profile of Condensate for Sustainable Applications
No full textThe sawn timber of beech (Fagus sylvatica L.), a pivotal hardwood species in Europe and of particular
importance in south-eastern Europe, is traditionally steamed before the drying process. Several decades
ago, this was done to equalize the color of the false heartwood and the rest of the wood, and steaming
lasted 36 to 48 hours. Nowadays, in Serbia and surrounding countries, more than 90% of beech timber
undergoes a process known as "light steaming" with the objective of inducing only a subtle color change.
Steaming, both indirect and direct, generates vast amounts of condensate (wastewater), which poses an
environmental challenge and must be chemically treated before being discharged into storm drains or
watercourses. This study focused specifically on the condensate produced during the indirect steaming
of beechwood timber. The process was carried out in an industrial chamber at a temperature of 95 ℃
and lasted 12 hours, including the heating and cooling phases. After two 12-hour steaming cycles, the
condensate sample was taken from different points of the tank in the chamber’s floor. The condensate
underwent a comprehensive analysis, determining total phenolic content, total flavonoid content, and
antioxidant activity. Moreover, qualitative and quantitative analyses were performed using HPLC
coupled with UV/VIS and MS/MS. The results demonstrated high content of phenols (1885±92.7 μg
gallic acid equivalents per mL of condensate; including specific phenolic compounds not typical for
other plants) and high flavonoid content (35.3±0.86 μg quercetin equivalents per mL of condensate).
Robust antioxidant activity was also observed (in DPPH assay IC50=42.9 µg/mL), emphasizing the
potential applications of condensates for direct use as biopesticides in agriculture or for isolation of
biologically active phenolic compounds that can be used in diverse industries, such as the
pharmaceutical and food industry. This simultaneously addresses environmental challenges in the wood
industry. Further research will extend to beech wood condensate generated during different phases of
the direct steaming process, but also to condensates from other wood species (walnut, oak). Furthermore,
the study will investigate how changes in steaming parameters (temperature and duration) affect both
the wood properties and the chemical composition of the condensate
Microplastic pollution effects on soil properties in forest ecosystems (Serbia)
No full textMicroplastic (MP) pollution is recognized as one of the biggest environmental problems due to multiple direct and indirect impacts on the environment. Existing research works indicate that the presence of MP in soil affects organic matter cycle, energy flow of terrestrial ecosystems, global production of CO2, climate, plant communities, crop production and biodiversity. There are only few studies dealing with the impact of MP on forest soil ecosystems. Research aimed to access the impact of MP on soil main chemical, physical and biological properties by comparing polluted and non-polluted forest sites in the three largest alluvial plains in Serbia is currently being carried out within the project "Evaluation of the Microplastic in the Soils of Serbia". Statistically significantly higher values of electrical conductivity, pH and particles > 0.02 mm have been measured in samples from polluted localities; while C, N and CEC have been measured significantly higher in samples from unpolluted sites. Prolonged microbial respiration (three months) has been measured and obtained data have been used as input for potentially mineralizable carbon and mineralization rate estimations, which are statistically significantly higher at all polluted sites. These results support the viewpoints that can be found in the literature, that the presence of MP in the soil affect organic carbon cycle and CO2 emissions. Differences in estimates indicate that microbial communities may be using MP particles as an additional food source. In order to establish the level of the impact of MP on soil properties and microbial activity in the longer term, the study is ongoing
Female professionals in forestry: status and empowerment in the Danube Region
No full textGender is a highly relevant meaning category in traditionally male-dominated forestry. In the
masculine nature of the working environment, women tend to perceive themselves as being less
prepared, secure, and economically capable of making the right decisions for the forest land they
own or manage. Moreover, female forestry professionals in Danube Region countries are less
represented in decision-making positions than their male colleagues while being more frequently
employed in research, knowledge transfer, forest pedagogics, nature protection and nursery
production. While caution applies to such gendered ascriptions in forest management, they do
call for closer inspection of female professionals in forestry. Women have been present in the
forestry workforce for many decades but have become visible only more recently.
The present contribution to the panel addresses the gap in forestry research on female
professionals’ status and empowerment with empirical evidence from Danube Region countries
incl. Bavaria, Czech Republic, Romania, Serbia, and Slovenia. Forestry is often characterized as
traditional and mature, with a weak innovation orientation. Attention for female professionals in
forestry sheds light on whether and how their careers “interrupt inequalities” and established
practices in forestry. The empirical basis consists of quantitative and qualitative data, which was
collected in the “Forests in Women’s Hands – Fem4Forest” Interreg project (2020-2022). The
survey data covers the views and perspectives of 663 women working in forestry in 10 countries,
complemented with qualitative insights into female work-life realities in the forestry sector from 56
semi-structured interviews.
The study answers several research questions to examine aspects of perceived (in)equalities and
empowerment in forestry, namely: (1) What motivates women to choose careers in forestry? (2)
How do women perceive and experience equal treatment at work? (3) Which obstacles female
professionals face in their careers? and (4) Which strategies and resources do female
professionals draw on to develop agency and achieve goals? Because of the vast differences
between the selected countries’ forestry sectors, the contribution concludes with some reflections
on the empowerment patterns of female forestry professionals in the Danube Region
The possibility of using CHATGPTT in the reading of thermodynamic state variables
No full textU termodinamičkim, a i ostalim inženjerskim proračunima, pojavljuju se podaci koji su
vezani za međusobne zavisnosti termodinamičkih veličina. Međusobne zavisnosti tih
veličina su veoma složene i obično su prikazane u obliku tabela. Postoje razne
inženjerski priručnici sa tabelama odakle se ove vrednosto mogu očitavati. Često se radi
dobijanja potrebnih vrednosti iz tabela mora izvršiti interpolacija. Interpolacija
podataka može biti složen, nepouzdan proces koji ponekad zahteva dosta vremena. U
ovom radu biće ispitana mogućnost upotrebe ChatGPT četbota na primeru dobijanja
vrednosti temperature ključanja vode u zavisnosti od pritiska, i obratno, dobijanja
vrednosti pritiska ključanja vode u zavisnosti od temperature. U eksperimentu opisanom
u ovom radu rezultati dobijeni pomoću ChatGPT četbota uporediće se sa tabličnim
vrednostima iz literature
Vokabular struke u univerzitetskim udžbenicima engleskog jezika: zastupljenost u tekstovima i strategije efikasnog usvajanja
No full textRazvijanje komunikativne kompetencije kroz usvajanje specifičnog vokabulara struke
povećava profesionalnu kompetenciju studenata omogućavajući im da čitaju stručne tekstove,
učestvuju u diskusijama i pišu izveštaje. Istraživanje obuhvata analizu zastupljenosti stručnih
reči u tekstovima za intenzivno čitanje u udžbenicima engleskog jezika biotehničkih struka.
Osim toga, ispituju se mogućnosti optimizacije procesa usvajanja izdvojenih reči kroz prateća
vežbanja. Rad daje prikaz strategija za efikasno usvajanje vokabulara struke koje uključuju
kontekstualno učenje kroz zadatke u kojima se oponašaju realne situacije budućih struka i
redovno ponavljanje novih reči i fraza kroz vežbe, kvizove i praktične zadatke, kao i primere
njihovog prilagođavanja potrebama studenata biotehnike
Application of Remote Sensing for Identifying Soil Erosion Processes on a Regional Scale: An Innovative Approach to Enhance the Erosion Potential Model
No full textSoil erosion represents a complex ecological issue that is present on a global level, with negative consequences for environmental quality, the conservation and availability of natural resources, population safety, and material security, both in rural and urban areas. To mitigate the harmful effects of soil erosion, a soil erosion map can be created. Broadly applied in the Balkan Peninsula region (Serbia, Bosnia and Herzegovina, Croatia, Slovenia, Montenegro, North Macedonia, Romania, Bulgaria, and Greece), the Erosion Potential Method (EPM) is an empirical erosion model that is widely applied in the process of creating soil erosion maps. In this study, an innovation in the process of the identification and mapping of erosion processes was made, creating a coefficient of the types and extent of erosion and slumps (phi), representing one of the most sensitive parameters in the EPM. The process of creating the coefficient (phi) consisted of applying remote sensing methods and satellite images from a Landsat mission. The research area for which the satellite images were obtained and thematic maps of erosion processes (coefficient phi) were created is the area of the Federation of Bosnia and Herzegovina and the Br & ccaron;ko District (situated in Bosnia and Herzegovina). The Google Earth Engine (GEE) platform was employed to process and retrieve Landsat 7 Enhanced Thematic Mapper plus (ETM+) and Landsat 8 Operational Land Imager and Thermal Infrared Sensor (OLI/TIRS) satellite imagery over a period of ten years (from 1 January 2010 to 31 December 2020). The mapping and identification of erosion processes were performed based on the Bare Soil Index (BSI) and by applying the equation for fractional bare soil cover. The spatial-temporal distribution of fractional bare soil cover enabled the definition of coefficient (phi) values in the field. An accuracy assessment was conducted based on 190 reference samples from the field using a confusion matrix, overall accuracy (OA), user accuracy (UA), producer accuracy (PA), and the Kappa statistic. Using the confusion matrix, an OA of 85.79% was obtained, while UA ranged from 33% to 100%, and PA ranged from 50% to 100%. Applying the Kappa statistic, an accuracy of 0.82 was obtained, indicating a high level of accuracy. The availability of a time series of multispectral satellite images for each month is a crucial element in monitoring the occurrence of erosion processes of various types (surface, mixed, and deep) in the field. Additionally, it contributes significantly to decision-making, strategies, and plans in the domain of erosion control work, the development of plans for identifying erosion-prone areas, plans for defense against torrential floods, and the creation of soil erosion maps at local, regional, and national levels
The market of wood forest products in Serbia and analysis of its dynamic elements
No full textThe most important product with a commodity character on the forest products market is wood, but also various wood assortments, which are the basic raw material in the wood industry. This paper analyzes the trends related to cutting, processing and sale of wood assortments (logs for cutting and logs for veneer peeling) from state forests in Serbia. In addition, these trends are analyzed separately for the commercially important species beech, oak and poplar. The methods used in the analysis are the Mann-Kendall trend test and the modified Mann-Kendall test with Hamed-Rao variance correction when the assumption of data independence is not met. The data were collected by the Statistical Office of the Republic of Serbia for the territory of Serbia (excluding AP Vojvodina and Kosovo and Metohija) and cover the periods 2002-2017 and 2003- -2017. The research aims to determine the trends in the market of wood products (assortments) related to production (cutting), processing, as an intermediate phase, and sale of wood assortments as the final phase. The purpose of this research is to identify the trends in the mentioned cate- gories, which provides a good basis for their prediction in the future. The subject of research is the volume of cutting, processing, and sales of wood assortments from state forests in Serbia. According to the results, a statistically significant growth trend in total cutting, processing and sales of wood assortments in the period 2002-2017 can be confirmed. The volume of processed wood assort- ments largely coincides with the realized volumes, which indicates that they were sold in the same year. A statistically significant trend was also observed in the production and sale of sawn timber (for beech, oak and poplar combined). The average annual growth rate for cutting was 2.5%, for processing 2.7% and for the sale of wood assortments 2.9%. As beech is the most widely represented wood species, the changes in supply and demand for this type of wood are mainly determined by the general market trends on the Serbian timber market. Production in forestry differs significantly from conventional production, so that the production possibilities in forestry are limited by the capacity of the forests and their resources. The timber market is therefore influenced and driven by this fact