Search Results (46)

The objective of this study was to determine the moisture content gradient over the thickness of glued laminated timber structures, manufactured as five-layer structures from two different species. Beech (Fagus sylvatica L.) or oak (Quercus robur L.) were used for the faces, and fir (Abies alba Mill.) or lime (Tilia cordata L.) were used for the core layers. Thus, four types of mixed glulam structures resulted. The layers were glued with a polyurethane adhesive for outdoor uses, and then cold-pressed. Samples were also prepared from each individual species as control specimens. All samples were exposed to two types of climate conditions, having cyclic and constant parameters. The first climate test involved cyclic variation in temperature and relative air humidity: 30 °C/40%/12 h, alternating with 10 °C/80%/12 h. The second climate test involved constant exposure conditions, but with higher humidity over a longer period: 15 °C/90%/3 weeks. The moisture content gradient between the layers of the structure was determined and correlated to the delamination effect, assessed by visual analysis. Based on the findings in this work, the lowest values of the moisture gradient were determined for the oak–fir mixed structures, resulting in the total absence of delamination and cracks between the outer oak layers and the inner fir layers. Full article

Within the current administrative boundaries of the city of Lublin, fragments of roadside tree avenues of various historical origins and periods of establishment have been preserved, including former tree-lined roads leading to rural and suburban residences from the 18th and 19th centuries. This avenue once led to the manor in Konstantynów and now serves as the main road through the campus of the John Paul II Catholic University of Lublin (Katolicki Uniwersytet Lubelski—KUL). As one of the last surviving elements of the former rural landscape, the Konstantynów avenue represents a symbolic link between past and future. The research combines acoustic tomography and chlorophyll fluorescence analysis, providing a precise and non-invasive evaluation of the internal structure and physiological performance of 34 small-leaved linden trees (Tilia cordata Mill.). This methodological approach allows for early detection of stress symptoms and structural degradation, offering a significant advancement over traditional visual assessments. The study area is an intensively used urban campus, where extensive surface sealing beneath tree canopies restricts rooting space. The degree of surface sealing (paving) directly beneath the tree canopies was also measured. Based on the statistical analysis, a weak a non-significant weak negative correlation (r = −0.117) was found between the proportion of sealed surfaces within the Tree Protection Zone (TPZ) and the Fv/Fm vitality index, indicating that higher levels of surface sealing may reduce tree vitality; however, this relationship was not statistically significant (p = 0.518). The study provides an evidence-based framework for conserving historic trees by integrating advanced diagnostic tools and quantifying environmental stress factors. It emphasizes the importance of improving rooting conditions, integrating heritage trees into urban planning strategies, and developing adaptive management practices to increase their resilience. The findings offer a model for developing innovative conservation strategies, applicable to historic green infrastructure across Europe and beyond. Full article

Urban expansion alters environmental conditions, influencing tree physiology and performance. Urban trees provide cooling, sequester carbon, support biodiversity, filter contaminants, and enhance human health. This study examines how two common urban trees—Norway Maple (Acer platanoides L.) and Little-leaved Linden (Tilia cordata Mill.)—respond to urban site conditions by assessing leaf morphology, stomatal, and gas exchange traits across street and urban park sites in Chicago, IL. Street trees exhibited structural trait adjustments, including smaller leaf area, reduced specific leaf area, and increased stomatal density, potentially reflecting acclimation to more compact and impervious conditions. Norway Maple showed stable photosynthetic assimilation (A), stomatal conductance (g_s), and transpiration (E) across sites, alongside higher intrinsic water-use efficiency (_iWUE), indicating a conservative water-use strategy. In contrast, Little-leaved Linden maintained A and g_s but showed elevated E and _iWUE at street sites, suggesting adaptive shifts in water-use dynamics under street microenvironments. These findings highlight how species-specific physiological strategies and local site conditions interact to shape tree function in cities and underscore the importance of incorporating functional traits into urban forestry planning to improve ecosystem services and climate resilience. Full article

Understanding and monitoring the phenological phases of trees is essential for ecological research and climate change studies. In this work, we present a comprehensive evaluation of state-of-the-art convolutional neural networks (CNNs) and transformer architectures for the automated classification of the flowering phase of Tilia cordata Mill. (small-leaved lime) based on a large set of real-world images acquired under natural field conditions. The study introduces a novel, automated image quality filtering approach using an XGBoost classifier trained on diverse exposure and sharpness features to ensure robust input data for subsequent deep learning models. Seven modern neural network architectures, including VGG16, ResNet50, EfficientNetB3, MobileNetV3 Large, ConvNeXt Tiny, Vision Transformer (ViT-B/16), and Swin Transformer Tiny, were fine-tuned and evaluated under a rigorous cross-validation protocol. All models achieved excellent performance, with cross-validated F1-scores exceeding 0.97 and balanced accuracy up to 0.993. The best results were obtained for ResNet50 and ConvNeXt Tiny (F1-score: 0.9879 ± 0.0077 and 0.9860 ± 0.0073, balanced accuracy: 0.9922 ± 0.0054 and 0.9927 ± 0.0042, respectively), indicating outstanding sensitivity and specificity for both flowering and non-flowering classes. Classical CNNs (VGG16, ResNet50, and ConvNeXt Tiny) demonstrated slightly superior robustness compared to transformer-based models, though all architectures maintained high generalization and minimal variance across folds. The integrated quality assessment and classification pipeline enables scalable, high-throughput monitoring of flowering phases in natural environments. The proposed methodology is adaptable to other plant species and locations, supporting future ecological monitoring and climate studies. Our key contributions are as follows: (i) introducing an automated exposure-quality filtering stage for field imagery; (ii) publishing a curated, season-long dataset of Tilia cordata images; and (iii) providing the first systematic cross-validated benchmark that contrasts classical CNNs with transformer architectures for phenological phase recognition. Full article

The phytoaccumulation of Fe, Mn, Cu, Zn, and Pb in Tilia cordata flowers and soils from six locations with varying degrees of anthropopressure in Bydgoszcz city and its surroundings (Poland) was assessed. Additionally, metal concentrations and soil enzymatic activity were analyzed. Enrichment Factor analysis revealed significant Zn enrichment at only one locality, supported by a geoaccumulation index value indicating moderate soil pollution. Total metal content in soils correlated with total organic carbon (TOC), while total iron content correlated with the clay fraction (<0.002 mm). Metal concentrations were comparable to the geochemical background levels for soils in Poland. Assessment of total metal contents in the topsoil surface layer from the six locations indicated that concentrations did not exceed permissible limits established by applicable legislation. The study showed that sampling locations influenced the activities of dehydrogenase (DHA), fluorescein diacetate hydrolysis (FDA), β-glucosidase (GL), and arylsulfatase (AR), and these activities correlated more strongly with pedogenic factors than with metal content. No elevated metal levels were detected in the dry mass of T. cordata flowers. Lead content did not exceed 10 mg·kg⁻¹ dry matter, in accordance with World Health Organization (WHO) recommendations. Continued monitoring of trace element levels in soils and T. cordata flowers, particularly in urban environments, is advisable. Full article

Water used in cleaning processes within the agri-food industry can be a vector for post-harvest contaminants, thus contributing to cross-contamination. The contamination risk is increased when water is not replaced between batches or when disinfection protocols are insufficient. Given the increasing focus in recent years on the potential of natural, non-invasive plant extracts to combat a variety of pathogens, including multidrug-resistant bacteria, environmental strains, and clinical isolates, this study aimed to evaluate the antibacterial activity of selected water-ethanol plant extracts against six opportunistic pathogens isolated from wash water in the agri-food industry, along with chromatographic analyses of the selected extracts. Plant extracts were obtained from the fruits, leaves, shoots, roots, and bark of 13 species. Antibacterial activity was assessed using the well diffusion method. The results indicated that antimicrobial activity was exhibited by six extracts: Tilia cordata Mill., Camellia sinensis, Quercus robur L., Betula pendula Roth, Rubus idaeus L., and Salix alba L. The extracts showed strain-dependent antimicrobial activity, with C. sinensis and R. idaeus up to 4.0 mm and 8.0 mm inhibition zones, respectively. P. aeruginosa and E. faecalis were the most susceptible strains, demonstrating the largest inhibition zones. In contrast, P. vulgaris and K. oxytoca were more resistant. The efficacy of the most active extracts can be linked to the presence of phytochemicals identified via GC-MS, including epicatechin, shikimic acid, quinic acid, gallic acid, and caffeine. These metabolites are known to interfere with bacterial cell structures and metabolic pathways. These studies may serve as a preliminary step toward the development of non-invasive water treatment methods for wash water. Full article

Trees growing in urban areas face increasing stress from atmospheric pollutants, with limited attention given to the early responses of young seedlings. This study aimed to address the knowledge gap regarding the effects of simulated pollutant exposure, specifically particulate matter (PM), elevated ozone (O₃), and carbon dioxide (CO₂) concentrations, on young seedlings of five tree species: Scots pine (Pinus sylvestris L.); Norway spruce (Picea abies (L.) H.Karst.); silver birch (Betula pendula Roth); small-leaved lime (Tilia cordata Mill.); and Norway maple (Acer platanoides L.). The main objectives of this paper were to evaluate the seedling stem growth response and the biochemical response of seedling foliage to pollutant exposure. Four treatments were performed on two- to three-year-old seedlings of the selected tree species: with PM (0.4 g per seedling) under combined O₃ = 180 ppb + CO₂ = 650 ppm; without PM under combined O₃ = 180 ppb + CO₂ = 650 ppm; with PM (0.4 g per seedling) under combined O₃ < 40–45 ppb + CO₂ < 400 ppm; and without PM under combined O₃ < 40–45 ppb + CO₂ < 400 ppm. Scots pine and Norway maple showed no changes in growth (stem height and diameter) and biochemical parameters (photosynthetic pigments, total polyphenol content (TPC), total flavonoids content (TFC), and total soluble sugars (TSS)), indicating a neutral response to the combined PM, O₃, and CO₂ treatment. The chlorophyll response to PM alone and in combination with elevated O₃ and CO₂ exposure varied, with silver birch increasing, Norway maple—neutral to increasing, Scots pine—neutral to decreasing, and Norway spruce and small-leaved lime—decreasing. The TPC indicated stress responses in Scots pine, small-leaved lime, and Norway maple under increased combined O₃ and CO₂ and in Norway spruce under single PM treatment. Hence, Scots pine and Norway maple seedlings showed greater resistance to increased PM under combined O₃ and CO₂ with minimal change in growth, while silver birch seedlings showed adaptation potential with increasing chlorophyll under simulated pollutant stress. Full article

Air pollution, particularly particulate matter (PM), poses a significant threat to urban environments and public health. This study aims to explore the impact of small-scale spatial and height variations on the ability of different roadside tree species: Tilia cordata Mill., Platanus × hispanica Mill. ex Münchh., and Sorbus intermedia (Ehrh.) Pers., to accumulate PM, providing insights for enhancing urban sustainability. Conducted along a high-traffic road in Warsaw, Poland, the research examines PM accumulation at varying heights and locations within tree canopies while also evaluating the influence of PM on photosynthetic efficiency. Results indicate substantial differences in PM accumulation between tree species and height ranges, with S. intermedia accumulating the highest PM levels. PM accumulation was greatest near the roadside and at lower canopy heights (1–1.5 m), while higher canopies and areas distant from the road showed reduced PM concentrations. T. cordata exhibited the highest PM accumulation on the side facing traffic, averaging 12% at 1–1.5 m height, while the interior recorded 5% at 2–2.5 m height. In S. intermedia, the roadside crown contributed the highest accumulation (14%) at 1–1.5 m height and only 6% on the side facing departing traffic at 2–2.5 m height. P. hispanica displayed higher efficiency in PM accumulation, reaching 11% at the roadside (1–1.5 m) and 7% at the top of the crown (3–3.5 m). Additionally, PM accumulation negatively impacted photosynthetic efficiency and chlorophyll content, with the highest PM levels correlating with reduced plant vitality. PCA analysis showed a stronger association between leaf-deposited PM and total chlorophyll content and that the presence of accumulated PM may significantly influence the chlorophyll content of the plants. These findings provide valuable guidance for urban planners in strategically planting roadside vegetation to maximize air quality improvement, offering a cost-effective and sustainable approach to mitigate urban pollution. Full article

Fallen leaves in cities are often treated as waste; therefore, they are collected, transported outside urban areas, and composted, which contributes to greenhouse gas (GHG) emissions. Instead of this conventional management approach, fallen leaves could be utilized as a feedstock in biogas production, helping to reduce GHG emissions, increase renewable energy generation, and provide fertilizer. The aim of this study was to compare the mono-digestion of fallen leaves from three tree species commonly found in parks and along streets—northern red oak (Quercus rubra L.), small-leaved lime (Tilia cordata Mill.), and Norway maple (Acer platanoides L.)—in both wet and dry anaerobic digestion (AD) systems. A biochemical methane potential (BMP) test was conducted in batch assays for each of the three substrates in both AD technologies at a temperature of 38 ± 1 °C. The highest specific methane yield (SMY) was obtained from Quercus leaves in wet AD technology, with a methane yield of 115.69 ± 4.11 NL kg_VS⁻¹. The lowest SMY (55.23 ± 3.36 NL kg_VS⁻¹) was observed during the dry AD of Tilia leaves. The type of technology had no significant impact on the SMY of Acer and Tilia leaves; however, the methane yield from Quercus leaves in wet AD was significantly higher (p < 0.05) than that from dry AD. Studies on the use of fallen leaves from Tilia cordata, Quercus rubra, and Acer platanoides as substrates in mono-digestion technology have shown their limited suitability for biogas production. Nevertheless, this feedstock may be more effectively used as a co-substrate, mainly due to the low concentrations of ammonia (NH₃) and hydrogen sulfide (H₂S) in the biogas produced from these leaves, both of which are considered inhibitors of the AD process. Full article

The genus Quercus, including species like pedunculate oak (Quercus robur L.), can play a key role in maintaining climate-resistant mixed forests due to its broad ecological spectrum and drought tolerance. Unfortunately, in some parts of Europe, clearcutting has drastically reduced the oak population. An example of this event is our survey of heritage Oak—Lime forests in European Russia, which were transformed into pure aspen stands. The aim of our study was to provide forecasts and silvicultural recommendations for the passive restoration of these forests. We took a chronosequence approach to assess changes associated with natural succession over 60 years. In our survey of the development of oaks, limes and accompanying tree species (aspen, birches, maples, elms), we used 190 plots ranging across a wide spectrum of forest disturbance due to clearcutting. We demonstrate that aspen reproduce rapidly by root suckers after cutting and occupy more than 60% of the space. But the dominance of aspen decreases continuously from the age of 30, and then the lime trees begin to dominate. Oak does not show successful natural regeneration. Therefore, we recommend planting oak seedlings or sowing acorns, i.e., active restoration, in combination with the natural restoration of lime. Full article

Trees growing in urban environments are often impacted by maintenance or construction work involving the cutting of roots. Tree protection zones have been proposed to avoid critical damage to the tree. However, despite incorporating quantitative information, they heavily rely on expert judgement that remains to be validated. In a study conducted across six parks in Quebec City, Canada, two commonly found tree species, Acer platanoides L. and Tilia cordata Mill., presumed to be different in terms of vulnerability to root damage, were subjected to a range of trenching treatments. The trees were between 23 and 40 cm diameter at breast height (DBH). A safety factor was calculated relating the turning moment the tree can withstand to the turning moment imposed by high winds likely to occur. The safety factor against uprooting was assessed for each tree before and after root trenching using a non-destructive pulling approach. The effects of tree species, distance to the trench, and their combined interaction were tested on tree stability. The relationship between tree stability and soil texture, tree characteristics, and the number of damaged roots were also tested. Safety factors were initially variable, ranging from 0.5 to 4.5. T. cordata safety factors were lower than those of A. platanoides and influenced by soil texture. Trenching treatments had no effect on the safety factor, even when two perpendicular trenches were dug at 1 m from the stem. No index of the amount of root damaged was significantly related to the safety factor. Root trenching treatments that encroached closer to the tree trunk than the recommended tree protection zones did not affect the stability of both species. Nevertheless, it is essential to recognize that other ecophysiological processes might still be influenced, and long-term monitoring is crucial. Both should be taken into account when determining these zones. Full article

In the Eastern Baltics, climatic changes are expected to alter forest composition favouring broadleaved species. The height growth of trees influences the productivity of stands and the competitiveness of species, particularly in mixed sites, thus emphasising the necessity for accurate projections. Accordingly, height models are paramount for projecting productivity and yields of stands. As tree height growth dynamics vary regionally, regional or even local models are needed. Based upon 214 National Forest Inventory plots and 510 individual canopy trees, dominant height growth for small-leaved lime (Tilia cordata Mill.) and Norway maple (Acer platanoides L.) in Latvia were analysed. Height growth was modelled using a generalised algebraic difference approach, testing several non-linear equations. The Sloboda (for lime) and Hossfeld I (for maple) models showed the best fit and were the most realistic, predicting slower initial and middle-age (maturing period) growth, yet also displayed higher asymptotes compared to Western Europe. The predicted height at the age of 80 years was 14–33 m and 13–34 m for lime and maple, accordingly. A longer establishment period and later growth culmination suggest longer rotation, highlighting the assessment of long-term risks. In this case, supplementation of the models with climatic effects appears advantageous. Full article

Beetles living in dead wood are species-specific, suggesting that beetle diversity may vary between different deciduous tree species. However, the patterns of diversity variation among deciduous trees are still poorly understood. In this study, we investigated the diversity of beetles associated with dead wood in the second decay stage in four protected areas of Lithuania, using trunk-emergence traps on Alnus glutinosa L., Gaertn. (black alder), Betula sp. L. (birch), Fraxinus excelsior L. (European ash), Populus tremula L. (European aspen), Quercus robur L. (common oak), and Tilia cordata Mill. (small-leaved linden). The findings of our study indicated variation in beetle diversity among the six tree species examined. We identified the greatest diversity of beetles in the decaying trunks of Quercus robur, followed by T. cordata, and F. excelsior. Our cluster analysis suggested a higher similarity in beetle diversity among tree species sharing the same type of bark; however, our db-RDA analysis showed that tree species explained more variance in the data than bark type. Our results support previous research highlighting the importance of dead wood species diversity in maintaining the diversity of beetles in forests. Within the context of current biodiversity decline, understanding the similarities or differences in beetle communities between tree species is key to tackling the loss of insect species. Full article

Drought and high evapotranspiration demands can jeopardise trees and shrubs in windbreaks and habitat corridors, where they are more exposed to the effects of extreme weather than in the forest. This study utilised chlorophyll fluorescence to assess how the leaf-level physiological processes of 13 woody species typically planted in Czech habitat corridors responded to the effects of naturally occurring drought and their ability to recover after rain. Linear electron flow (LEF) responded only weakly to the drought, indicating high levels of photorespiration. Trees and shrubs increased the proportion of energy which was dissipated in a harmless way (Φ_NPQ) during drought and decreased the proportion of energy dissipated through non-regulated processes (Φ_NO). In this way, they reduced processes potentially leading to the production of reactive oxygen species. All species except Tilia cordata Mill. maintained high Φ_NPQ even after its release from drought. Tilia cordata was potentially the most susceptible tree to drought due to its low LEF and high Φ_NO. The most drought-resistant tree species appeared to be Acer campestre L. and shrubs such as Prunus spinosa L., Viburnum lantana L, and Crataegus monogyna L. These shrubs may be planted at the sunny edges of habitat corridors. The woody species identified as resistant to drought in habitat corridors may also be considered resistant in a warming climate or suitable for planting in the urban environment which is generally warmer and drier than in a forest. Full article

Senile trees in historic church gardens have natural, aesthetic, historical, and cultural value. Cutting them down too hastily annihilates the achievements of entire generations. We should try to preserve the greenery surrounding historic churches and integrate it into a clear compositional arrangement with the sacral architecture. The primary purpose of the paper was to describe the process of inventorying 200-year-old trees and to present the revalorization project for the garden around the historic Orthodox church in Horostyta, located in the Lublin Voivodeship, in southeastern Poland. The church complex consists of a wooden 18th-century building, bell tower, garden, and cemetery. Within the church garden’s boundaries, there are 15 trees, with two predominant species: Acer pseudoplatanus L. and Tilia cordata Mill. These trees are of varying ages and health conditions. We used acoustic tomography to perform tree health diagnostics. Three trees, for which the initial visual assessment was disturbing, were examined thanks to detailed tomography tests. Then, through a project adapting the church garden to the health conditions of the ancient trees, they were separated from users by flowerbeds and no small architectural objects were placed around them. The presented development concept forms a compromise between tradition and the modern user’s needs. In 2007, a general renovation of the temple building was completed. Currently, the presented project for the church garden is being implemented. Full article