Background: Rainfall redistribution by forest canopies is a key hydrological process influencing water availability in semi-arid ecosystems. However, information remains limited on how pine species and stand development affect rainfall partitioning in reforested landscapes of the Mixteca Alta region of Oaxaca, Mexico. This study evaluated throughfall, stemflow, and interception in Pinus pseudostrobus and Pinus greggii plantations ranging from 6 to 56 years old. Results: Rainfall partitioning was monitored throughout the rainy season using throughfall collectors and stemflow collars installed in seven pine plantations. Throughfall generally decreased with stand age, whereas interception increased as canopy development progressed. Pinus pseudostrobus consistently allowed greater throughfall and exhibited lower interception losses than P. greggii, particularly in younger stands. In contrast, P. greggii showed greater canopy retention of rainfall, reflecting differences in canopy structure and density. Stemflow contributed only a small proportion of total precipitation and declined with increasing stand age in both species. Log-linear models indicated significant relationships between incident precipitation and rainfall redistribution components, while structural attributes such as crown diameter and basal area were associated with observed hydrological responses Conclusions: Species identity and stand age significantly influenced rainfall partitioning in semi-arid pine plantations. The greater interception observed in older stands and in P. greggii highlights the importance of canopy structure in regulating water inputs to the forest floor. These findings provide useful guidance for species selection and reforestation planning aimed at sustaining hydrological ecosystem services in water-limited environments.
Background: The aim of this study was to assess the decomposition of litter and subsequent nutrient release from different eucalypt stand with different clones in the neotropical savanna. Litter mass loss for each clone was assessed through the random distribution of over 1,080 litter bags on the soil surface. Chemical analyses of macronutrients (N, P, K, Ca, Mg, and S) and carbon (C) in the remaining litter were performed. An exponential and polynomial model was used to describe the decomposition and macronutrients, respectively. An ANOVA was conducted, and mean comparisons were performed using Tukey's test (alpha = 0.05). Results: At the end of the experiment, the remaining litter mass was 11% for clone GG100 and 15% for clone EAC 1528. The residual concentrations of C, K, and Mg in the litter were associated with mass loss, while N, P, Ca, and S increased up to 720 days. The levels of N, P, and Mg were higher in clone GG100, whereas Ca and S were higher in clone EAC 1528 (p = 0.05). Conclusions: This study highlights that long-term research on litter decomposition in eucalypt stands contributes to a better understanding of nutrient cycling dynamics. Different eucalyptus stands exhibited distinct nutrient release patterns throughout the litter decomposition process.
Background: The acoustic quality of a guitar is directly influenced by the wood species used in its construction. Brazil has a diverse range of tree species with potential for lutherie, which could reduce production costs and encourage sustainable cultivation. In this context, this study evaluated the suitabilityofAraucaria angustifolia, a native species from southern Brazil, for use in guitar manufacturing. Acoustic, anatomical, chemical, physical, and mechanical properties of wood samples from three trees were analyzed, followed by the construction and evaluation of a guitar prototype. Results: The results demonstrated promising acoustic performance, with a sound velocity of 4657 m & centerdot;s-1, a fundamental frequency of 199.1 Hz, and a logarithmic decay of 0.019 s. The wood showed suitability for use in the soundboard and back of the guitar. Significant correlations were observed between acoustic and mechanical properties and anatomical and chemical characteristics, including bordered pit diameter, solubility in ethanol and water, basic density, and tangential hardness. The wood exhibited a density of 430 kg & centerdot;m-3 and lower shrinkage values compared with conventional tonewoods. Mechanical behavior was consistent with low-density woods, with an elastic modulus of 10,469 MPa. Evaluations conducted by professional musicians classified the instrument's tonal quality as "Good" or "Very Good". Conclusions: The findings indicate that Araucaria angustifolia has significant potential for guitar manufacturing, especially in applications requiring lightweight tonewoods with favorable acoustic performance. The species represents a promising alternative for lutherie, contributing to the diversification of raw materials and the valorization of native Brazilian woods.
Background: In Brazil, the production of wood derivatives is mainly based on planted eucalyptus forests, often established in areas marginal to agriculture, such as steep terrain. However, intra-site variability in these plantations is still poorly explored, especially in operational silviculture contexts. Topographic gradients can modify the availability of water and light, influencing plant performance and wood quality. In this context, this study aimed to evaluate the effect of topographic variation along a toposequence on the morphological and anatomical characteristics of leaves, as well as on the anatomical and chemical properties, basic density, and higher heating value of the wood, in a clonal plantation of Eucalyptus spp. Results: Position in the toposequence significantly influenced several characteristics (p < 0.10). Trees located at the base of the slope exhibited, on average, higher leaf water content (1.37 g. g-1), larger leaf area (47.95 cm2) and lower total extractive content in the wood (3.47%). The leaves of trees in the middle of the slope had the lowest water content (1.16 g.g-1). At the top of the slope, where the trees with the lowest height growth were found (15.26 m), the leaves had a higher proportion of palisade and spongy parenchyma (0.62), one of the smallest leaf areas (28.9 cm2) and higher total extractive content (7.20%). Conclusions: Topographic variation promotes integrated adjustments in leaf and wood characteristics, reflecting adaptive strategies to local resource availability conditions. These results reinforce the importance of considering intra-site variability in forest management and in the selection of genetic materials better adapted to heterogeneous environments.
ABSTRACT Background: The steel industry demands raw materials capable of improving charcoal quality and production efficiency. The objective of the study was to identify and quantify the potential advantages of Corymbia wood for charcoal production compared with Eucalyptus and to evaluate the influence of dendrometric, wood and charcoal properties on the differentiation of these genetic materials. Results: The Corymbia hybrids exhibited lower height growth than Eucalyptus, while presenting wood that was, on average, 20% denser and contained 44% less heartwood. The resulting charcoal showed, on average, 2% higher gravimetric yield, 15% higher density, and 8% greater mechanical resistance than Eucalyptus charcoal. Basic density was identified as the variable most strongly associated with the differentiation among the evaluated genera and hybrids of C. torelliana x C. citriodora. Conclusions: Although Corymbia hybrids showed lower growth, they produced a charcoal mass per hectare similar to that of E. urophylla x E. grandis. These results indicate the potential of the evaluated Corymbia hybrids as an alternative source of raw material for steelmaking charcoal production.
