Search Results (314)

A growing global demand for wood, coupled with the role of this material in low-carbon strategies, is fuelling interest in fast-growing plantations, including short-rotation forestry (SRF) and agroforestry systems. However, evidence of the physical–mechanical properties and possible uses of non-native hardwoods in the Mediterranean environment remains limited. This study aimed to address this current knowledge gap by evaluating the main physical and mechanical properties of six fast-growing non-native tree species cultivated in experimental plots in Calabria, southern Italy. The wood of Eucalyptus occidentalis Endl., E. × trabutii (M. Vilm. ex Trab.) A. Chev., E. camaldulensis Dehnh., E. bridgesiana R.T.Baker, Melia azedarach L., and Paulownia tomentosa (Thunb.) Steud., were evaluated. The dynamic elastic modulus (MOE_d) was estimated on standing trees using stress waves (TreeSonic™). In the laboratory, swelling and shrinkage (ISO 13061-14 and 16), static modulus of elasticity (MOE_s) and modulus of rupture (MOR) (EN 408), and compressive strength (ISO 13061-16) were determined. The data were analysed using one-way ANOVA, followed by Tukey’s HSD test where appropriate. Swelling and shrinkage showed no significant differences (p > 0.05). One-way ANOVA revealed a significant effect of species on MOE_s (p < 0.001). Both standing-tree stress-wave measurements (MOE_d) and laboratory tests (MOE_s, MOR, and compression strength) revealed significant variability in stiffness and resistance among the species examined. The positive relationship observed between MOE_d and MOE_s indicates that stress-wave testing can serve as a practical, rapid tool for ranking plantation material at an early stage, thereby supporting early decision-making in SRF and agroforestry systems. These results provide comparative evidence for species and clonal selection, and to optimise the allocation of plantation resources to targeted value chains in Mediterranean environments. Full article

In Hungary, a fast-growing Empress tree hybrid (×Paulownia Clone in vitro 112) also known as Smaragdfa^® has been developed as a low-density plantation species seeking industrial utilization. Many potential industrial applications presuppose its bonding. The presence of adhesives in bonded layered assemblies, with differing climatic conditions on the internal and outer side, may induce undesired internal strains due to restricted water vapor diffusion, especially in the case of Smaragdfa as a low-density wood species. For decades, lasures have been specifically formulated with a molecular structure that allows partial vapor transmission while hindering water diffusion. Lasure-coated samples were used as control samples to identify, among the different custom-made MW adhesives, the one with diffusion properties closest to those of the lasure. Uncoated Smaragdfa wood samples were used as the baseline reference to evaluate the effect of different adhesive and coating systems on water vapor diffusion. Smaragdfa samples were prepared both uncoated and coated with different adhesive and lasure layers. Experiments were conducted following ISO 12572 and ASTM E96 standards using the cup method, with all specimens pre-conditioned to 12% moisture content. Results showed that the uncoated Smaragdfa exhibited the highest diffusion coefficient (δ = 7.02 × 10⁻¹³ kg/(m·s·Pa)) and flow rate (G = 0.055763 g/h), while the commercial adhesive-coated sample displayed an 84% reduction in diffusion capacity (δ = 1.15 × 10⁻¹³ kg/(m·s·Pa)), indicating a strong vapor-blocking effect. The lasure coating allowed partial vapor transmission, confirming its semi-permeable nature. Adhesives formulated with varying polyol molecular weights (Series 1–5) revealed a clear molecular-weight-dependent diffusion behavior: low-MW systems (S1) acted as strong diffusion barriers comparable to lasure-coated samples (SMW_L), in the same time high-MW systems (S4, S5) permitted excessive diffusion but induced microcracking, while intermediate formulations (S2, S3) achieved the most balanced performance, combining moderate diffusion with structural stability. Overall, the findings confirm that adhesive layers significantly influence water vapor transmission through Smaragdfa wood, with the degree of hindrance closely related to the molecular weight of the polyol matrix. The optimized formulations (S2, S3) demonstrate promising potential for use in bonded assemblies and engineered wood products where controlled vapor diffusion and mechanical reliability are critical in order to support reduced strains caused by water vapor. Full article

Protected area management plays a crucial role in conserving biodiversity, especially in areas where increasing demand for natural resources is associated with fast-growing human populations, such as West Africa. Investigating the perceptions of people with first-hand knowledge of protected area management provides important insights about biodiversity conservation, wildlife law enforcement, and human activities to inform adaptive management. Using 442 semi-structured interviews, we assessed the perceptions of park rangers and local residents in and around Fazao-Malfakassa National Park in Togo, West Africa, which was managed by the non-profit Franz Weber Foundation from 1990 to 2015, and since 2015 has been managed by the government of Togo. Both rangers and residents reported significant economic concerns following the park’s transfer from private to state management, with salary declines negatively affecting rangers and declines in community development projects and income-generating activities negatively affecting residents. Law enforcement capacity and resources also declined under state management, severely undermining the ability of rangers to curb illegal activities in the park, especially poaching and the destruction of trees to harvest wild honey and produce commercial charcoal. All rangers and most residents who had experience with both private and state park management preferred private management. There is an urgent need to increase surveillance and law enforcement capacity in the park to combat poaching and other illegal activities, and to engage local communities in the park’s long-term protection. To this end, rangers and residents are calling for change, and specifically recommend returning the park to competent private management to safeguard Togo’s last large refuge for nature and wildlife. Full article

As a fast-growing timber tree species with a wide cultivation area, poplar is facing the problem of declining economic benefits under long-term monoculture. Intercropping provides an effective solution. Using Illumina Miseq sequencing, we analyzed soil microbiomes under four patterns: poplar monoculture, and intercropping with amorpha fruticosa, black locust, or cassia seed. The results showed that the Alpha diversity index of intercropping area was significantly higher than that of single planting poplar area under intercropping and monoculture conditions. In the intercropping area, the highest species richness was the intercropping of poplar and black locust, and the lowest was the intercropping of poplar and amorpha fruticosa. The dominant microorganisms in the intercropping mode were Vicinamibacterales, and the fungi were Alternaia and Enterocarpus. In the single planting poplar area, a large number of bacteria gathered in the soil were Dongia and Alphaproteobacteria, and fungi were Fusarium and Mortierella. Functional prediction results showed that the biosynthetic function of ansamycin was the highest in the bacterial community. In the intercropping area, the functional abundance of methanol oxidation, sulfate respiration, sulfate compound respiration, nitrate denitrification, nitrite denitrification, and nitrous oxide denitrification was higher than that in the single planting poplar area. On the contrary, the abundance of methanotrophy function is lower than that of single planting poplar area. In the fungal community, the functional abundance of animal pathogens and the animal pathogen–dung saprotroph–endophyte–plant saprotroph–soil saprotroph–wood saprotroph group in the monoculture poplar area was higher than that in the three intercropping areas. In summary, the intercropping mode of poplar is better than the monoculture mode, and the species richness is the highest when poplar and black locust are intercropped. Therefore, the intercropping pattern of poplar and other tree species improved microbial community. This provides some theoretical guidance for the subsequent solution of continuous cropping obstacles in poplar. Full article

Fast-growing invasive tree species management produces a significant amount of low-density and low-value biomass, which offers a chance for waste valorization in the environmentally friendly construction sector. This study examines the utilization potential of low-value natural waste materials of tree bark, obtained from invasive hardwood species, in the production of environmentally friendly building mortars. More specifically, this study focuses on mixing bark powder of black locust (Robinia pseudoacacia L.) and tree-of-heaven (Ailanthus altissima (Miller) Swingle), with two commercial commonly found lime-based mortar powders in five different ratios of bark content (0%, 5%, 10%, 20% and 30%) characterizing the produced composites, in terms of physical, hygroscopic and mechanical properties. Slightly lighter composites were created with the use of bark additives especially at the bark content of 20% and 30%. As regards the compressive strength, the bark shares of 10% and 20% exhibited the most beneficial performance among those studied, though only the weaker performance of mortar type (M1) benefited significantly from bark incorporation. For both mortars, the composites containing black locust bark presented higher resistance to compression strength and elasticity, demonstrating higher composite integration in general and milder, plastic fraction in relation to tree-of-heaven bark-based specimens, the properties of which are considered crucial for the durability of structural materials. However, black locust bark exhibited higher water absorption compared to tree-of-heaven-based specimens. Despite the drawback of higher hygroscopicity, the results show that black locust bark, especially at lower incorporation rates (10–20%), is a promising functional additive for generating lighter, more ductile mortars, supporting the creation of novel building materials and sustainable waste management. Full article

Climate change is intensifying drought frequency and severity, posing increasing challenges for tropical forest species whose growth and survival depend on water availability. Ochroma pyramidale (Cav. ex Lam.) Urb. (balsa) is a fast-growing pioneer tree that plays important ecological roles, and it is valued for its lightweight timber, yet little is known about its drought tolerance or intraspecific variation among populations. This study evaluated the morphophysiological responses of O. pyramidale seedlings from three provenances spanning a rainfall gradient (850–6275 mm year⁻¹) under controlled soil moisture levels. The experiment followed a completely randomized factorial design with two factors, provenance (high-, medium-, and low-rainfall origins) and soil moisture (100%, 50%, and 20% field capacity), with six replications per treatment (n = 54 total plants). Drought significantly affected growth, water status, and physiological variables. Seedlings maintained high relative water content and photosynthetic pigment concentration under moderate stress (50% field capacity) but showed marked declines at 20% field capacity. Soluble sugar accumulation increased with drought intensity, suggesting osmotic adjustment, while root proliferation was enhanced under moderate stress (50% FC), evidenced by significantly higher Total Root Length (TRL) and Number of Branch Points (NBP). Provenance effects were weak, with only the number of leaves differing significantly among provenances. These results demonstrate that O. pyramidale tolerates moderate drought through physiological adjustment and root plasticity, supporting its use in reforestation and restoration initiatives in water-limited tropical environments. Full article

Acacia melanoxylon R.Br. demonstrates strong biological nitrogen–fixation capacity and favourable economic returns, making it a promising candidate for the development of subtropical forestry in South Asia. It is a fast–growing leguminous tree species widely promoted for cultivation in China, and it is also one of the ideal tree species for improving soil fertility in forest lands. What are the synergistic mechanisms between A. melanoxylon-Eucalyptus stands and pure Eucalyptus spp.? Current theories regarding A. melanoxylon–Eucalyptus systems remain relatively fragmented due to the lack of effective silvicultural measures, resistance studies, and comprehensive ecological–economic benefit evaluations. The absence of an integrated analytical framework for holistic research on A. melanoxylon–Eucalyptus systems makes it difficult to summarise and comprehensively analyse their growth and development, thereby limiting the optimisation and widespread application of their models. This study employed CiteSpace bibliometric analysis and qualitative methods to explore ideal tree species combination patterns, elucidate their intrinsic eco–economic synergistic mechanisms, and reasonably reveal their collaborative potential. This study systematically reviewed silvicultural management, stress physiology, ecological security, and economic policy using the Chinese and English literature published from 2010 to 2025. The narrative synthesis results indicated that strip intercropping (7:3) is widely documented as an effective model for creating vertical niche complementarity, whereby canopy light and thermal utilisation by A. melanoxylon species improve subsoil nutrient cycling by enhancing stand structure. A conceptual full–cycle economic assessment framework was proposed to measure carbon sequestration and timber premiums. Correspondingly, this conversion of implicit ecological services into explicit market values acted as a critical tool for decision–making in assessing benefit. A three–dimensional “cultivation strategy–physiological ecology–value assessment” assessment framework was established. This framework demonstrated how to move from wanting to maximise the output of an individual component to maximising the value of the whole system. It theorised and provided guidance on resolving the complementary conflict between “ecology–economy” in the management of sustainable multifunctional plantations. Full article

Poplars (Populus L.) are fast-growing, widely distributed trees with high ecological, economic, and climate-mitigation value, making them central to diverse agroforestry systems worldwide. This study presents a comprehensive bibliometric and content-based review of global poplar-based agroforestry research, using Scopus and Web of Science databases and a PRISMA-guided screening process to identify 496 peer-reviewed publications, covering publications from 1987 to 2024. Results show a steady rise in scientific output, with a notable acceleration after 2013, dominated by agriculture, forestry, and environmental sciences, with strong international contributions and research themes focused on productivity, carbon sequestration, biodiversity, and economic viability. A wide range of Populus species and hybrids is employed globally, supporting functions from crop production and soil enhancement to climate mitigation and ecological restoration. Poplar-based systems offer substantial benefits for soil health, biodiversity, and carbon storage, but also involve trade-offs related to tree–crop interactions, such as competition for light reducing understory crop yields in high-density arrangements, management intensity, and regional conditions. Poplars provide a wide array of provisioning, regulating, and supporting ecosystem services, from supplying food, fodder, timber, and biomass to moderating microclimates, protecting soil and water resources, and restoring habitats, while supporting a broad diversity of agricultural and horticultural crops. However, several critical gaps—including a geographic research imbalance, socio-economic and adoption barriers, limited understanding of tree–crop interactions, and insufficient long-term monitoring—continue to constrain widespread adoption and limit the full realization of the potential of poplar-based agroforestry systems. Full article

The application of organic fertilizer is an effective way to improve soil fertility and promote seedling growth. Toona fargesii (T. fargesii) is a fast-growing tree with high commercial value due to its excellent timber quality. However, the mechanism underlying its rapid growth at the seedling stage in red soil remains unclear. Here, we investigated the effects of cow manure application (OF group) on soil nutrients and rhizosphere microbial communities in red soil, as well as how it promotes the seedling growth of T. fargesii. Seedlings in the OF group showed a significantly higher specific growth rate than those in the unfertilized control (CK) group (73.51 ± 11.82% vs. 34.90 ± 5.49%, p = 0.022). This growth promotion was accompanied by an increase in soil pH (6.36 ± 0.01 vs. 6.22 ± 0.02, p = 0.001) and a concurrent decrease in NO₃⁻-N (10.60 ± 3.20 vs. 22.58 ± 3.49, p = 0.044). High-throughput sequencing demonstrated that cow manure tended to enhance bacterial diversity while decreasing fungal diversity. The OF treatment significantly enriched the relative abundances of bacterial phyla Myxococcota, Bacteroidota, Firmicutes, and Proteobacteria, while reducing Chloroflexi. For fungi, the relative abundances of Calcarisporiellomycota and Chytridiomycota were reduced under OF treatment. Redundancy analysis indicated that soil pH and organic matter (OM) content were the main environmental drivers shaping rhizosphere microbial communities. Our results demonstrated that short-term cow manure application raised soil pH and shifted the microbiome, coinciding with promoted seedling growth. This study provides insights into the microbiome-mediated rapid growth of tree seedlings in red soil. It implies that applying cow manure is an effective way to promote seedling performance in the early stages. Full article

Eucalyptus urophylla is a core tree species for short-rotation industrial timber plantations in South and Southwest China. However, the dynamic correlation rules of its growth traits during the full rotation period remain unclear, and the theoretical research on early selection is insufficient. In this study, 12 pure E. urophylla clones (including U6 and MLA as controls) were used as plant materials. Based on the data of tree height (H), diameter at breast height (DBH, D), and individual tree volume (V) from 0.5 to 7.5 years old, the correlation rules of early and late growth traits were explored, core predictive traits were screened, and the optimal selection age was determined through rank correlation, phenotypic and genetic correlation analyses, combined with regression modeling and selection efficiency calculation. Early selection of E. urophylla clones was feasible: after 3.5 years, the early–late phenotypic and genetic correlation coefficients of H, D, and V all reached significant or highly significant levels, and the genetic correlation coefficients were greater than the phenotypic ones, indicating that genetic factors dominated trait correlations with little environmental interference. All five established early selection regression models passed the highly significant test. Among them, the models of D-early versus D-late, V-early versus V-late, and D-early versus V-late had the highest coefficients of determination (0.9293–0.9385), making them the optimal selection traits; the models of H-early versus H-late and H-early versus V-late had lower coefficients of determination (0.8010–0.8364) due to errors in height measurement. The best selection effect was achieved within 1/2–2/3 of the rotation period: for a 6-year rotation period (pulpwood), the optimal selection age was 3.5 years old (annual efficiency 1.318); for an 8-year rotation period (medium-diameter timber), it was 4.5 years old (annual efficiency 1.345); and for a 12-year rotation period (large-diameter timber), it was 6.5 years old (annual efficiency 1.379). This study not only fills the theoretical gap in early selection of E. urophylla during the full rotation period but also constructs an integrated early selection technology system of “trait screening—model prediction—age determination”. It provides key support for shortening the breeding cycle of E. urophylla and achieving precise control of breeding costs and offers important references for early selection research on fast-growing broad-leaved tree species worldwide. Full article

In Korea, a persistent shortage of Japanese larch (Larix kaempferi) seeds and the high costs of managing seed orchards have created a significant demand for alternative reforestation methods. This pilot study, conducted over nine years, evaluated the field performance of somatic embryo-derived larch seedlings (emblings) across 14.4 hectares in nine different locations. The study addressed challenges with SE technology, such as limited genetic diversity and the inconsistent quality of seedlings due to year-round production. Despite these initial issues and other environmental interferences, the statistical analysis revealed age to be the sole significant fixed factor driving tree growth and root collar diameter (RCD) increase (p < 0.001 for both). Crucially, the growth rate (slope) for height and RCD was not statistically different between the embling and seed-derived groups (seedlings). Furthermore, the GLMM for survival confirmed that age was not a significant predictor (p > 0.35 for both types). Instead, site-specific factors were the primary drivers of overall survival and growth variation. The random effects analysis showed that site heterogeneity was substantial for height (${\mathit{\sigma }}_{\mathrm{Site}}=0.8256$, indicating that somatic embryo-derived larch plantlets were more sensitive to site-specific environmental conditions than seed-derived seedlings (${\mathit{\sigma }}^2$ was 1.078 for embling survival and 0.4074 for seedling survival). We also found no significant difference in overall tree form or evidence that emblings developed dominant side branches. This research demonstrates that SE technology can produce high-quality larch emblings that are statistically equivalent to their seedling counterparts in long-term growth trajectory and RCD development. It confirms that this method offers a viable and cost-effective solution to Korea’s seed shortage without sacrificing long-term growth or survival. Full article

Soil organic carbon (SOC) is a critical component of the soil carbon pool, significantly influencing soil fertility and forest ecosystem productivity. Eucalyptus grandis (Rose Gum), one of the most widely introduced and economically valuable fast-growing tree species worldwide, plays an indispensable role in pulpwood production, construction, and bioenergy, and is commonly established and managed in successive rotations in operational practice. Despite its importance, the effects of successive planting on SOC and its labile fractions in plantation soils remain poorly understood. In May 2017, a space-for-time substitution approach was employed to study the effects of successive planting of E. grandis plantations on SOC and its labile fractions, including dissolved organic carbon, light-fraction organic carbon, particulate organic carbon, microbial biomass carbon, and readily oxidizable carbon. The results indicated that the content of SOC and labile organic carbon (LOC) fractions declined concomitant with an increase in successive planting generations. Specifically, total SOC content significantly decreased from 12.63 g·kg⁻¹ in the first-generation forest to 9.37 g·kg⁻¹ in the third-generation forest. The contents of LOC fractions also showed a significant decrease from the first to the second generation, but the rate of this decline slowed in the third generation. The soil carbon pool management index (CPMI) decreased significantly from 100 in the control forest to 46.64 in the third-generation plantation. Redundancy analysis identified water-soluble nitrogen and total nitrogen as the principal common factors exerting influence over SOC and its labile fractions in E. grandis plantations. These findings indicate that successive planting of E. grandis in artificial forests primarily reduces SOC and LOC fractions by lowering soil nutrient content, leading to a decline in soil carbon pool quality. The findings of this study may help provide a scientific basis for the sustainable development of E. grandis plantations in this region. Full article

This study provides the first comprehensive, field-inventory-based assessment of urban ecosystem services within a Russian university campus, focusing on the woody vegetation of the Lobachevsky State University of Nizhny Novgorod. Utilizing a detailed field tree inventory combined with the i-Tree framework (including i-Tree Eco, i-Tree Canopy, UFORE, and i-Tree Hydro models), we quantified the campus’s capacity for carbon storage and sequestration, air pollutant removal, and stormwater runoff mitigation. The campus green infrastructure, comprising 1887 trees across 32 species with a density of 145.5 stems per hectare, demonstrated significant ecological value. Results show a carbon storage density of 26.61 t C ha⁻¹ and an annual gross carbon sequestration of 11.43 tons. Furthermore, the campus trees removed 1213.7 kg of air pollutants annually (a deposition rate of 9.35 g m⁻²), with ozone, particulate matter, and sulfur dioxide showing the highest deposition. The campus also retained 956.1 m³ of stormwater annually. These findings, particularly the high carbon sequestration rates, are attributed to the dominance of relatively young, fast-growing tree species. This research establishes a critical baseline for understanding urban ecosystem services in a previously under-researched geographical context. The detailed, empirical data offers crucial insights for urban planners and policymakers in Nizhny Novgorod and beyond, advocating for the strategic integration of ecosystem services assessments into campus planning and broader urban green infrastructure development across Russian cities. The study underscores the significant role of university campuses as vital components of urban green infrastructure, contributing substantially to environmental sustainability and human well-being. Full article

Chinese fir, as a crucial fast-growing tree species in the hilly regions of southern China, exhibits spatial structure characteristics that directly influence both the ecological functionality and productivity of its stands. This study focused on Chinese fir plantations in the Yangkou State-Owned Forest Farm, Fujian Province. Using UAV-LiDAR point cloud data, individual tree parameters such as height and crown width were extracted, and a DBH inversion model was constructed by integrating machine learning algorithms. Spatial structure parameters were quantified through weighted Voronoi diagrams. A comprehensive evaluation system was established based on the combined weighting method and fuzzy evaluation model to systematically analyze spatial structure characteristics and their evolutionary patterns across different age classes. The results demonstrated that growth environment indicators (openness and openness ratio) progressively declined with the stand’s age, reflecting deteriorating light conditions due to increasing canopy closure. Growth superiority (size ratio and angle competition index) exhibited a “V”-shaped trend, with the most intense competition occurring in the middle-aged stands before stabilizing in the over-mature stage. The resource utilization efficiency (uniform angle and forest layer index) showed continuous optimization, reaching optimal spatial configuration in over-mature stands. This study developed a spatial structure evaluation system for Chinese fir plantations by combining UAV data and cloud modeling, elucidating structural characteristics and developmental patterns across different growth stages, thereby providing theoretical foundations and technical support for close-to-nature management and the precision quality improvement of Chinese fir plantations. Full article

Urban tree biodiversity represents a valuable natural resource. However, some fast-growing tree species with limited esthetic value play an important ecological role by colonizing degraded areas, such as closed landfills. Our observations indicate that trees like Betula pendula (Roth), Acer negundo (L.), and Populus tremula (L.) reached the size of adult trees in less than 30 years after the landfill’s closure in the 1990s, forming a nature area similar to a natural forest. A resident survey conducted among the inhabitants of Zgierz confirmed that the lack of space provides opportunities for various forms of recreation. The example analyzed indicates a trend that can be replicated in other cities with minimal human intervention and low financial costs for landfill reclamation. The case study presents an ecological approach to managing degraded sites, where nature determines the quality of the soil environment by eliminating pollutants from the residential surroundings. Furthermore, the research framework provides a basis for developing future models for cleaning up urban landfill sites and promoting placemaking. This pilot study shows a model for old landfills in Europe with well-developed spontaneous vegetation that can be transformed into recreation and sports facilities in the urban areas with industrial past times. Full article