Search Results (81)

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

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

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

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

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

Restoration plantations in subtropical regions, often established with fast-growing tree species such as Acacia auriculiformis A. Cunn. ex Benth and Eucalyptus urophylla S. T. Blake, are frequently developed on highly weathered soils characterized by phosphorus deficiency. To investigate strategies for mitigating nutrient imbalances in such ecosystems, a long-term (≥13 years) fertilization experiment was designed. The experiment involved three fertilization regimes: nitrogen fertilizer alone (N), phosphorus fertilizer alone (P), and a combination of nitrogen and phosphorus (NP) fertilizers. The objective of this study was to investigate the effects of long-term fertilization practices on soil quality in subtropical plantations using a soil quality index (SQI). Consequently, all conventional soil physical, chemical, and biological indicators associated with the SQI responses to long-term fertilization treatments were systematically evaluated, and a principal component analysis (PCA) was conducted, along with a literature review, to develop a minimum dataset (MDS) for calculating the SQI. Three physical indicators (silt, clay, and soil water content), three chemical indicators (soil organic carbon, inorganic nitrogen, and total phosphorus), and two biological indicators (microbial biomass carbon and phosphodiesterase enzyme activity) were finally chosen for the MDS from a total dataset (TDS) of eighteen soil indicators. This study shows that the MDS provided a strong representation of the TDS data (R² = 0.81), and the SQI was positively correlated with litter mass (R² = 0.37). An analysis of individual soil indicators in the MDS revealed that phosphorus addition through fertilization (P and NP treatments) significantly enhanced the soil phosphorus pool (64–101%) in the subtropical plantation ecosystem. Long-term fertilization did not significantly change the soil quality, as measured using the SQI, in either the Acacia auriculiformis (p = 0.25) or Eucalyptus urophylla (p = 0.45) plantation, and no significant differences were observed between the two plantation types. These findings suggest that the MDS can serve as a quantitative and effective tool for long-term soil quality monitoring during the process of forest sustainable management. Full article

Accurate estimation of plantation aboveground biomass (AGB) is critical for quantifying carbon cycles and informing sustainable forest resource management, but enhancing estimation accuracy remains a key challenge. Although tree height and stand age are recognized as critical predictors for enhancing AGB models in addition to spectral vegetation indices, their individual and combined contributions in regional plantation forests remain insufficiently quantified, especially concerning the potential for leveraging the distinct characteristics of fast-growing plantations to facilitate AGB estimation. This study developed multi-source remote sensing-based Eucalyptus AGB estimation models for Nanning, Guangxi, integrating stand age and tree height to assess their impacts. Stand age was mapped from Landsat time-series imagery, and tree height was derived from UAV-LiDAR data. Plot-level reference AGB was obtained using fused UAV and terrestrial LiDAR point clouds. A random forest model, incorporating these variables with Sentinel-2 spectral information and topography, then achieved regional AGB estimation. The findings demonstrate that (1) tree height serves as the most influential predictor for AGB estimation at the regional scale, yielding a robust model performance (R² = 0.84). (2) Tree height captures the majority of the explanatory power associated with stand age. Once tree height was included as a predictor, the subsequent addition of stand age offered no significant improvement in model accuracy (R² = 0.85). (3) Given the challenges in obtaining precise tree height data and the robust correlation between stand age and tree height in fast-growing plantations, the integration of stand age substantially improved the accuracy of AGB estimations (from the spectral model of R² = 0.54 to R² = 0.74), with performance approaching that of tree height-based models (ΔR² = 0.10). Consequently, in fast-growing plantations, which are often characterized by high stand homogeneity, a hybrid model incorporating stand age can offer a reliable and cost-effective solution for AGB estimation. Full article

The evaluation of crop production that influences surface and groundwater quality is of growing importance in the context of agricultural sustainability in Europe. The primary aim of this study was to understand the relationship between gross nitrogen surplus in land and nitrate concentrations in surface and groundwater. The analysis was based on datasets collected from 2010 to 2021. Nitrate levels were categorized into three distinct quality classes based on the percentage of monitoring points, reflecting a spectrum from high quality, defined as nitrate levels below 25 mg/dm³, to poor quality, characterized by levels exceeding 50 mg/dm³. Redundancy analysis indicated that Gross Nitrogen Balance, a fertilizer use predictor, partially influences water quality, potentially due to long-term effects. Model selection for Gross Nitrogen Balance based on the AIC_c information criterion identified catch crops (or green cover), high-intensity agriculture, Natura 2000 sites, nitrogen-fixing plants, organic farming, fast-growing tree plantations, and EU27 states as predictors in the group of supported models. The best-fit model revealed differences between EU27 states for Gross Nitrogen Balance. Catch crops and Natura 2000 sites were also significant predictors, the former associated with a positive and the latter with a negative effect on nitrogen balance. In turn, WEI+ increased with nitrogen balance input but decreased with organic farming, indicating that promoting organic practices could help save water resources. Poland emerged as a country with relatively good water quality compared to several European counterparts, such as Denmark, Belgium, Malta, Czechia, Germany, and Lithuania. The implications of this research extend significantly to evaluation of the effects of the Common Agricultural Policy within the European Union. Full article

Ochroma lagopus, a fast-growing tropical tree species, faces fertilization challenges due to slope heterogeneity in plantations. This study examined 3-year-old Ochroma lagopus at upper and lower slope positions under five treatments: CK (no fertilizer), F1 (600 g/plant), F2 (800 g/plant), F3 (1000 g/plant), and F4 (1200 g/plant) of secondary macronutrient water-soluble fertilizer. Growth parameters and N-P-K stoichiometry were analyzed. Key results: (1) Height increased continuously with fertilizer dosage at both slopes, while DBH peaked and then declined. (2) At upper slopes (nutrient-poor soil), fertilization elevated leaf P but reduced branch N/K and increased root P/K. At lower slopes (nutrient-rich soil), late-stage leaf N increased significantly, with roots accumulating P/K via a “storage strategy”. Stoichiometric thresholds indicated N-K co-limitation (early-mid stage) shifting to P limitation (late stage) on upper slopes and persistent N-K co-limitation on lower slopes. (3) PCA identified F4 (1200 g/plant) and F1 (600 g/plant) as optimal for upper and lower slopes, respectively. This research provides a theoretical basis for precision fertilization in Ochroma lagopus plantations, emphasizing slope-specific nutrient status and element interactions for dosage optimization. Full article

Logs supplied in Papua New Guinea and Indonesia are predominantly sourced from fast-growing tree species of plantation forests. The timber primarily consists of sapwood, which is highly susceptible to biodeterioration. At a training center, CCA (chromated copper arsenate) is still used for wood preservation, while in the wood industry, ACQ (alkaline copper quaternary) is commonly applied to enhance the service life of timber. In the future, polystyrene impregnation or other non-biocidal treatments could potentially serve this purpose. This study aimed to determine the discoloration and resistance of polystyrene-impregnated and CCA-preserved woods. Wood samples, Anisoptera thurifera and Octomeles sumatrana from Papua New Guinea, and Anthocephalus cadamba and Falcataria moluccana from Indonesia, were used. The wood samples were treated with polystyrene impregnation, CCA preservation, or left untreated, then exposed at the PNG Forest Research Institute site for four months. After treatment, the color change in polystyrene-impregnated wood was minor, whereas CCA-preserved wood exhibited a noticeably different color compared to untreated wood. The average polymer loading for polystyrene-impregnated wood reached 147%, while the average CCA retention was 8.4 kg/m³. Densities of untreated-, polystyrene-, and CCA-wood were 0.42, 0.64, and 0.45 g/cm³, respectively, and moisture contents were 15.8%, 9.4%, and 13.4%, respectively. CCA preservation proved highly effective in preventing termite attacks; however, CCA is hazardous to living organisms, including humans. Polystyrene impregnation also significantly improved wood resistance to subterranean termites, as indicated by lower weight loss and a higher protection level compared to untreated wood. Additionally, polystyrene treatment is nonhazardous and safe for living organisms, making it a promising option for enhancing wood resistance to termite attacks in the future as an alternative to the biocides currently in use. Full article

Dehesas are mosaics of open grassland and standalone trees that are diversity reservoirs. However, they have recently faced abandonment and intensification, being replaced by plantations of fast-growing trees or subject to encroachment. Following a change in dehesa communities and structure, a change in soil microbial diversity and functionality in dehesas is expected, but dehesas’ microbial diversity is still a big unknown. In this work, we bring to light the soil prokaryotic taxonomic diversity in dehesa ecosystems and present a first approach to assessing their metabolic diversity through metabarcoding data. For this, we compared three dehesas dominated by different tree species: (i) one dehesa dominated by Quercus ilex; (ii) one dominated by Pinus pinea; and (iii) one dominated by a mixture of Q. ilex and Q. suber. At each dehesa, samples were taken under the canopy and in the open grassland, as well as through two seasons of peak vegetation productivity (autumn and spring). Our results show the following findings: (1) seasonality plays an important role in prokaryotic richness, showing higher values in autumn, and higher evenness in spring; (2) the effect of seasonality on the soil’s prokaryotic diversity is often modulated by the effect of tree species and canopy; (3) taxonomic diversity is driven mainly by the site effects, i.e., the opposite of the metabolic diversity that seemed to be driven by complex interactions among seasons, tree species, and canopies. Full article

Chinese fir (Cunninghamia lanceolata) is an important fast-growing tree species for timber production and ecological protection in China. Yet, its tissue culture for seedling propagation is hampered by low proliferation and poor quality. Light quality is vital for seedling proliferation and growth, but the regulatory mechanisms remain poorly understood. In this study, a transcriptome and metabolome were integrated to explore light quality’s effects on adventitious shoot proliferation of tissue-cultured Chinese fir seedlings. The seedlings were grown under red, green, blue, and composite light-emitting diode conditions, with white light as the control. Results showed that blue and blue-dominant composite light enhanced proliferation by promoting auxin and cytokinin and increased biomass. Red light promoted shoot height, leaf area, and carotenoid content due to elevated gibberellin and reduced auxins and cytokinin levels but inhibited proliferation due to hormonal imbalances. Green light increased abscisic acid levels and suppressed growth. Transcriptome and metabolome analyses identified key pathways including plant hormone signal transduction, photosynthesis, and flavonoid and carotenoid biosynthesis. Weighted gene co-expression network analysis (WGCNA) identified four key genes regulated by light quality that further modulated hormone biosynthesis and signaling transduction. This research provided insights for optimizing Chinese fir seedling proliferation and growth, contributing to sustainable plantation management. Full article

As a fast-growing tree species, Ochroma lagopus Swartz has a greater demand for nutrients, and urea and slow-release fertilizer addition can promote the growth and development of O. lagopus. This experiment explored the effects of urea and slow-release fertilizer on the growth and nutrient uptake of O. lagopus plantation forests. The results of the study can provide a theoretical basis for the cultivation and management of O. lagopus plantation forests. At the end of June 2023, a two-year-old O. lagopus was used as the study’s object at Mengwing Farm, Mengla County, Xishuangbanna Dai Autonomous Prefecture, Yunnan Province, China. Fertilizer is applied through root outer ring application. Seven treatments of no N control (CK) and urea and slow-release fertilizers 300 g/plant (N1, H1), 450 g/plant (N2, H2), and 600 g/plant (N3, H3) were set up to determine the breast height, diameter at breast height, as well as the nutrient contents of leaves, branches, roots, and soils of the trees. The DBH and tree height were higher under N addition than in the CK, and both were highest in H3 at 90 d after fertilization, with 16.92% and 14.64% higher than CK, respectively. The overall change in C content of each organ was not obvious, N content increased with the increase in fertilizer application, and the change pattern of P content was not consistent. Soil N content showed a significant increase with the increase in N application, while P and K content showed a trend of increasing and then decreasing, and soil N content of slow-release fertilizer treatments was higher than that of urea treatments under the same amount of N application. The soil N content was higher in the slow-release fertilizer treatment than in the urea treatment regardless of the amount of N applied. The soil N content was highly significantly positively correlated with the N content of leaves, branches, and roots. There was a highly significant allometric growth relationship among the C, N, and P content of each organ. The N addition had a significant effect on the growth and the nutrient content of each organ and soil. O. lagopus mainly adapted to changes in the soil N content by adjusting the N and P content of each organ, and the optimal effect was observed in H3. In the future, an appropriate amount of P fertilizer should be applied to complement N fertilizer, urea and slow-release fertilizer can also be applied. Full article

Mixed-species plantations involving Eucalyptus and Acacia trees are an effective alternative for managing sustainable plantations. In this study, we evaluated the growth, productivity, nutrient return, and soil properties of a mixed Eucalyptus hybrid (Eucalyptus camaldulensis Dehnh. × E. urophylla S.T. Blake; E) and Acacia auriculiformis A. Cunn. ex Benth. plantation (A) and Eucalyptus hybrid and A. auriculiformis plantations. The mixed Eucalyptus hybrid and A. auriculiformis plantation included three ratios at E33:A67, E50:A50, and E67:A33, while the Eucalyptus (E100) and A. auriculiformis (A100) plantations were established on degraded lands in the Had Wanakorn Forestry Research and Student Training Station, Prachuap Khiri Khan province, Thailand. Three replications within a plot size of 20 × 20 m² were designed to plant Eucalyptus hybrid and A. auriculiformis seedlings at a spacing of 2 × 3 m². The diameters at breast height (DBH) and height (H) of the Eucalyptus hybrid and A. auriculiformis were measured and monitored after planting for five years. The aboveground biomass of the five-year-old mixed and monoculture plantations was then estimated. Litterfall production and nutrient return from the mixed and monoculture plantations were measured for three years. In addition, soil samples at depths of 0–5, 5–10, and 10–20 cm were collected to analyze the soil’s chemical properties. Differences in growth, aboveground biomass, litterfall production, nutrient return, and soil properties were analyzed and tested using Tukey’s HSD. The results indicated that both the DBH and H of the Eucalyptus hybrid in the mixed and monoculture plantations were not significantly different (p > 0.05). Similarly, the DBH and H of A. auriculiformis in each treatment were also not significantly different (p > 0.05). However, the DBH and H of the Eucalyptus hybrid were higher than those of A. auriculiformis. The aboveground biomass for the mixed plantation ratios E50:A50, E100, E67:A33, and E33:A67 was not significantly different, while the stem biomass was the highest in E100. Litterfall production was influenced by the proportion of the Eucalyptus hybrid relative to A. auriculiformis, but the monoculture A100 plantation had the highest litter production. The nitrogen return estimated for the mixed plantation was between A100 and E100. Similarly, the total nitrogen in the topsoil (0–5 cm) of the mixed plantation was higher than that in the monoculture E100 plantation. These results indicate that mixing A. auriculiformis with Eucalyptus can improve soil nutrients and nutrient cycling and increase nutrient returns, suggesting that mixed plantations are an effective option for sustainable plantation management and can mitigate the negative environmental impacts of Eucalyptus monocultures. Full article