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GL Beams Reinforced with Plywood in the Outer Layer
Glulam beams are increasingly used in the construction industry because of their high strength and the possibility of using round timber with smaller cross-sections. The load-bearing capacity of beams is strongly related to the quality of the outer layers and, in the case of wood, especially the tension zones. For these reasons, this study decided to replace the outer lamella with tensile plywood. The produced beams were subjected to static bending strength and modulus of elasticity evaluation. It was shown that the best static bending strength values were obtained for beams containing plywood in the tension layer. However, the change in structure in the tension zone of beams made of glued laminated timber results not only in an increase in the load capacity of elements produced in this way but also in a decrease in the range/range of the obtained results of bending strength. This way of modifying the construction of glued laminated beams allows a more rational use of available pine timber.
Hidden effects of aluminum coagulant on freshwater mussels: Responses of Anodonta anatina and Unio tumidus to lake restoration
Among the trees: shade promotes the growth and higher survival of juvenile toads
getation, including trees, significantly shapes microhabitats for amphibians due to the leaf litter input, providing stable shelter, creating a microclimate or indirectly through trophic interactions. It is known that some species can survive in a highly modified urban environment. Species associated with open space can find stable habitats in urban and human-transformed areas, but is the impact of shading (presence of canopy cover) significant in their case? We focus on the effect of solar exposure on the growth rate of juvenile green toads Bufotes viridis in fruit and canopy manipulation treatments. The main aim of the study was to examine the selected habitat traits promoting post-metamorphic growth of the green toad in semi-open enclosures. We investigated differences between exposure/land cover variants, i.e., sunny site (open area with direct solar exposure) and shadow site (shady site with a tree canopy cover). Using imitation fruits and real cherry plum Prunus cerasifera fruits (non-native tree species), we checked whether amphibian growth is related to the additional structure that fruit lying on the ground created (a more heterogeneous surface structure) or to a trophic character (additional food source due to attracting invertebrates). We conducted a 40-day rearing experiment in three variants with two replications in semi-open enclosures with 20 juvenile toads each. We found differences in snout-vent length and body mass index investigated due to site exposure during post-metamorphic growth. The survival rate of juvenile toads in the shaded site was higher than in sunny sites. We demonstrated a positive effect of the tree’s shade, regardless of the fleshy fruit’s presence on the ground. Toads benefit from developing at sites with reduced solar exposure (i.e., with a tree canopy), resulting in intensive growth and higher survival rate. Thus, there is an opportunity for planners and urban authorities to manage habitats for amphibian conservation purposes by creating a shaded zone, even for open habitat species, especially in transformed areas such as cities. Our results indicate that the beneficial effect of the lying fruit on the growth of juveniles is limited to specific conditions, and understanding this requires further research.
Impact of Pathogenic Fungi on Leaf Surface Wettability: A Case Study of Erysiphe castaneigena
ABSTRACTLeaf surface wettability significantly influences rainfall interception and the overall water balance within forest ecosystems. However, the effects of biological factors, particularly fungi, on this critical property have not been extensively documented. In this study, we assessed the impact of Erysiphe castaneigena, a powdery mildew fungus, on the wettability of leaves from Japanese chestnut trees. We compared the wettability of infected and uninfected leaves by measuring the contact angles of water droplets on their surfaces. Our analysis revealed that leaves infected with the powdery mildew fungus displayed significantly higher hydrophobicity compared with uninfected leaves. This increased hydrophobicity correlated with the densification of the mycelium as the fungal coverage of the leaf surface expanded. These findings emphasize the substantial influence of phyllosphere microorganisms such as powdery mildew fungi on leaf wettability. Our results also enhance our understanding of the ecohydrological implications of microbial interactions on leaf surfaces, highlighting the need for further research into how these processes impact broader ecological and hydrological systems.
Properties of Particle Boards Containing Polymer Waste
Nowadays, a significant increase in interest in renewable energy sources can be observed. Wind farms have been one of the solutions representing this trend for many years. One of the important elements of windmills is the blades. The data indicate that what to do with the blades after their use is a global problem, and so it is important to find a way to recycle them. Hence, this work aimed to use these blades in the production of wood-based materials. Two fractions of a fragmented blade were used for the tests: a small one and large one. Boards characterized by densities of 650 kg/m3 and 700 kg/m3 were produced, in which the assumed substitution of the wood material with a polymer was 20% or 40%. Mechanical properties such as bending strength (MOR), modulus of elasticity (MOE), and internal bond strength (IB) were investigated. The 2S65 variant achieved the highest static bending strength and a modulus of elasticity of 2625 N/mm2. The second best result was noted for the 4S65 variant, which was significantly different from the 2S65 variant. In the case of the variants with a density of 700 kg/m3, no significant differences were found and their results were significantly lower. Moreover, research on thickness swelling (TS) after 24 h of immersion and water absorption (WA) were also conducted. The obtained results indicate that the manufactured boards are characterized by good physical and mechanical properties.
Neoteric Biofilms Applied to Enhance the Safety Characteristics of Ras Cheese during Ripening
The milk’s natural flora, or the starter, can preserve cheesemaking and allow for microbial competition. This investigation aimed to improve cheese safety and assess its characteristics using probiotic cell pellets (LCP) or cell-free extracts (CFS). Cheese samples were collected from different areas to investigate the current contamination situation. Six CFSs of probiotics were assessed as antifungal against toxigenic fungi using liquid and solid media and their aflatoxin reduction impact. The most effective CFS was chosen for cheese coating in nanoemulsion. Coated cheese with CFS, LCP, and LCP-CFS was assessed against control for changes in chemical composition, ripening indications, rheological properties, and microbiology. Results showed significant contamination levels in the collected samples, and toxic fungi were present. Lactobacillus rhamnosus CFS has aflatoxins reducibility in liquid media. During cheese ripening, uncoated cheese showed higher fat, protein, salt content, soluble nitrogen, total volatile fatty acids, tyrosine, and tryptophan contents than coated samples, except for LCP-coating treatment. Cheese rheology indicated that coating treatments had the lowest hardness, cohesiveness, gumminess, chewiness, and springiness compared to uncoated cheese. Uncoated cheese had the highest yeast and mold counts compared to the treated ones. The LCP-CFS-coated cheese showed no Aspergillus cells for up to 40 days. Uncoated Ras cheese recorded slightly lower flavor, body, texture, and appearance scores than coated cheeses. In conclusion, coating cheese with L. rhamnosus nanoemulsion has antifungal and antiaflatoxigenic properties, even for LCP, CFS, and CFS-LCP, which could extend cheese shelf life.
The Content of Phenolic Compounds and Organic Acids in Two Tagetes patula Cultivars Flowers and Its Dependence on Light Colour and Substrate
The main focus of the study was to determine the content of phenolic acids, flavonoids, and organic acids in the flowers of Tagetes patula ‘Petite Gold’ and ‘Petite Orange’. The growth of the plants was assessed depending on the cultivation conditions. The above plants were illuminated with white light, whereas the ‘Petite Gold’ ones with white light enhanced with blue or red light. Both cultivars grew in a two-level-mineral compounds organic substrate. The research showed that the French marigold flowers were rich in phenolic compounds and organic acids. The ‘Petite Gold’ flowers had more bioactive compounds compared with the ‘Petite Orange’ flowers. Three flavonoids, 10 phenolic acids and seven organic acids were found in the ‘Petite Gold’ flowers. The artificial lighting used during the cultivation of the plants showed diversified influence on the content of organic compounds in their flowers. The measurements of the plants’ morphological traits and the number of inflorescences showed that illumination with red light resulted in a better effect. Large plants with numerous inflorescences grew in the substrate with a lower content of nutrients.
The impact of resin harvest history on properties of Scots pine wood tissue
This study was conducted in Central Europe (Poland) in pine forests that were subjected to the process of resin harvesting in the 1970s. Forty trees were designated for the study, which had one or two resin blazes. The objectives of the experiment were to determine the effect of resin tapping on the changes in annual growth, wood density, and mechanical strength of wood in the damaged trees. Resin tapping affected the development dynamics, especially in trees with a single resin blaze. In addition, bark cutting affected wood density over the cross-section. However, no significant variation was found in terms of the mechanical properties of wood, which may support the theory of adaptive tree growth and optimization of tree’s structure to its functions.
Propolis extract as a bio-based modifier of urea-formaldehyde adhesive in particleboard production
Potential of Pine Needle Biomass for Bioethanol Production
Currently, fossil fuels are used to produce fuels and electricity, which are finite sources and have a negative impact on the natural environment. An excellent alternative to these fuels is biofuels, such as bioethanol from waste forest biomass. Pine needles are one of the most important available forest biomass materials with s significant impact on local understory vegetation. Forest waste biomass, which is a rich source of lignocellulose, can be used in various ways, such as for the eco-economical production of bioethanol. The aim of this study was to analyze the possibilities of bioethanol production from pine needle biomass obtained from forest land following different soil preparations and logging residue management. The pine needle dry matter yield, chemical components of pine needle biomass (cellulose, hemicellulose, lignin), and the amount of ethanol yield per hectare were evaluated. The highest average yield pine needle equal to 6.17 Mg∙ha−1 was observed. Bioethanol yield per hectare from this biomass was the highest for plowing with the LPZ-75 plow and was 1.08 m3∙ha−1. The discussed results were confirmed by detailed statistical analysis. To sum up, the researched pine needle biomass turned out to be an interesting raw material with the potential for bioethanol production.
Functional ecosystem parameters: Soil respiration and diversity of mite (Acari, Mesostigmata) communities after disturbance in a Late Cambrian bedrock environment
AbstractWe analyzed the changes in ecosystem functions (soil respiration and Mesostigmata mite abundance, species richness and diversity) on various habitats after flooding by highly mineralized and acidic drainage water with fine As‐rich pyrite sediments, on a fragment of a natural ecosystem. In total, 177 plots that represented six types of habitats (undisturbed: pine mixed forests, Salix spp. thickets, Juncus effusus communities, wet meadows, and disturbed: bare ground and dead Salix spp. thickets) were sampled twice, in June 2019 and September 2020. Our study revealed that flooding affected essential ecosystem parameters, such as soil Mesostigmata mite abundance, species richness and diversity, and soil respiration, via an extreme decrease of soil pH. In total, 968 mites were collected from pooled data from the two samplings. Mite abundance, species richness and diversity were mainly shaped by habitat type and soil pH, and partially by soil respiration. These parameters were lower in disturbed habitats (bare ground and dead Salix spp. thickets) as compared with undisturbed ones. The highest mean mite density was recorded from mixed forests (4750 ± 600 ind. m−2) and wet meadows (2678 ± 361 ind. m−2), whereas the lowest in bare ground (449 ± 113 ind. m−2) and dead Salix spp. thickets (537 ± 146 ind. m−2). We noticed that mite diversity may be helpful to predict future changes in the physicochemical parameters of soils in disturbed areas. The vegetation patches built up by species adapted to grow in habitats characterized by relatively high metal and metalloid content (J. effusus and Salix spp.) represent an intermediate state of function of ecosystems in the study area.
Long-Term Climate Sensitivity of Resin-Tapped and Non-Resin-Tapped Scots Pine Trees Based on Tree Ring Width and Blue Intensity
The resin tapping of pine trees in Poland ended in the early 1990s. However, we can still find individual trees, and sometimes larger groups of trees, that were tapped. This study focused on the effect of the mechanical wounding of trees during resin tapping on the growth and climatic sensitivity of pine trees. The study concerned a 160-year-old pine stand in northwestern Poland in which resin tapping was last performed in the 1970s. All the trees had remained standing because of their high quality, which had destined them for seed collection. The stand included both resin-tapped (RT) and non-RT (NRT) trees. Our study was based on a dendrochronological analysis of two signals—annual tree ring widths (TRWs) and their delta blue intensity (DBI). We observed a significant increase in annual TRW after resin tapping had ceased, alongside a decrease in the DBI. The temporal stability in growth response was examined using daily climatic correlations from 1921 to 2021. It was found that the climatic sensitivity of RT and NRT pines was similar. There were differences in only some of the years, most while resin tapping was occurring, and then approximately 20 years after the resin tapping had ceased. However, these were small differences that mainly related to the strength of the correlation. It was also discovered that we can obtain different types of information from the study of TRWs and DBI.
Current Trends in the Use of Biomass in the Manufacture of Rigid Polyurethane Foams: A Review
This paper discusses methods of using biomass from the agriculture, forestry, food and aquaculture industries as potential raw materials for bio-polyols and as fillers in the production of rigid polyurethane (RPUR) foams. Various aspects of obtaining bio-polyols are discussed, as well as the impact of replacing petrochemical polyols with bio-polyols on the properties of foams. Special attention is paid to the conversion of vegetable oils and lignin. Another important aspect of the research is the use of biomass as foam fillers. Chemical and physical modifications are discussed, and important factors, such as the type and origin of biomass, particle size and amount, affecting the foaming process, microstructure and properties of RPUR foams are identified. The advantages and disadvantages of using biomass in foam production are described. It is found that bio-polyols can replace (at least partially) petrochemical polyols while maintaining the high insulation and strength of foams. In the case of the use of biomass as fillers, it is found that the shaping of their properties is largely dependent on the specific characteristics of the filler particles. This requires further research into process optimization but allows for the fine-tuning of RPUR foam properties to meet specific requirements.
Potential Identification of Root System Architecture Using GPR for Tree Translocation as a Sustainable Forestry Task: A Case Study of the Wild Service Tree
Sustainable economic development serves society but requires taking over space, often at the expense of areas occupied by single trees or even parts of forest areas. Techniques for transplanting adult trees used in various conflict situations at the interface of economy and nature work as a tool for sustainable management of urbanized and industrial areas, as well as, in certain circumstances, forest or naturally valuable areas. This study aimed to evaluate the effectiveness of ground-penetrating radar (GPR) in determining the horizontal and vertical extent of tree root systems before transplantation. Employing this non-invasive method to map root system architecture aids in the appropriate equipment selection and helps define the dimensions and depth of trenches to minimize root damage during excavation. This study specifically focused on the root systems of wild service trees (Sorbus torminalis (L.) Crantz) found in a limestone mine area, where some specimens were planned to be transplanted, as the species is protected under law in Poland. The root systems were scanned with a ground-penetrating radar equipped with a 750 MHz antenna. Then, the root balls were dug out, and the root parameters and other dendrometric parameters were measured. The GPR survey and manual root analyses provided rich comparative graphic material. The number of the main roots detected by the GPR was comparable to those inventoried after extracting the stump. The research was carried out in problematic soil, causing non-standard deformations of the root systems. Especially in such conditions, identifying unusually arranged roots using the GPR method is valuable because it helps in a detailed planning of the transplanting process, minimizing root breakage during the activities carried out, which increases the survival chances of the transplanted tree in a new location.
The effect of commercial thinning in Scots pine stands on the growth of black cherry
Abstract Black cherry (Prunus serotina Ehrh.) is one of the most abundant invasive species found in Polish forests. The mass occurrence of this species in pine stands is one of the main problems of silviculture. Therefore, the paper addresses the problem of the effect of commercial thinning, which increases the access of light to the lower layers of the stand, on the annual growth of rings and the development of black cherry. The study attempted to determine the strength of the progression of the black cherry threat as expressed by increased diameter increment. It was assumed that the thickness increment of mature black cherry individuals after thinning would be significantly greater compared to the average thickness increment before thinning. Over time after the treatment, the average growth of sprouts of black cherry will decrease. Six pine stands differing in age and timing of the silvicultural treatment in the Golub–Dobrzyn Forest District (N 57°81′42″ E 50°20′19″) were analysed. A positive effect of commercial thinning on the thickness increment of black cherry was found in all the studied plots. Over time, the average increment of black cherries resulting from the clearance decreased. Conducting late thinning, in pine stands where black cherry occurs, results in an increased threat of its expansion. To limit the development of black cherry at this stage of pine stand management, two solutions are possible. The first is to abandon late thinning or reduce the intensity of the treatment, which will inhibit its rapid expansion. The second scenario is to limit the occurrence of black cherry a few years before thinning, perform thinning and introduce understorey or underplanting from native competitive tree species.
The Potential of the Bioenergy Market in the European Union—An Overview of Energy Biomass Resources
One of the bases of the European policy and energy strategy is the biomass and bioenergy obtained from it. It is estimated that by 2023, the annual demand for biomass will have increased from the current level of 7 EJ to 10 EJ. There are significant differences between estimates of the bioenergy potential due to the fact that the authors of publications do not use consistent methodology and assumptions. Forest biomass, agricultural residues, and energy crops are the three main sources of biomass for energy production. Energy crops are likely to become the most important source of biomass. Land use and its changes are a key issue in the sustainable production of bioenergy as the availability of biomass determines its potential for energy security. This article is a review of the latest publications on the bioenergy potential of the member-states of the European Union. The consumption of energy and its potential were presented, with a special focus on renewable sources, especially biomass. The potential of biomass resources was presented and the types of biomass and its sources of origin were indicated. The research was conducted on the member-states of the European Union, whose policy is based on long-term development from the dependence on fossil resources to the dominance of renewable resources. As results from the research, in recent years, there has been a significant increase in the potential of both forest biomass (from 4.8 EJ per annum to the forecasted 15 EJ per annum) and agricultural biomass from (from 2.3 EJ per annum to the forecasted 7 EJ per annum). The increase in the demand for energy biomass in the EU member-states is balanced by partial imports from non-EU countries.
