ABSTRACT Background: Guadua is a bamboo genus widely distributed in the state of Acre and holds significant potential for various applications; however, it remains largely underexplored. Bamboo morphology and anatomy are fundamental for accurate botanical identification, providing valuable insights for bioprospecting and influencing its functional properties. This study aimed to describe the morphology and perform an anatomical characterization of mature culms of Guadua acreana. Results: Mature culms were collected from a bamboo grove located on a private lot adjacent to FUNTAC (Fundação de Tecnologia do Estado do Acre), at geographic coordinates Latitude 9°56’46.01” South and Longitude 67°52’8.86” West. A total of 10 culms were analyzed at FUNTAC. Anatomical sections were prepared and examined using optical microscopy, revealing size variations in the vascular bundles, with increasing metaxylem and phloem dimensions toward the inner culm region, which may influence mechanical properties or water conduction efficiency. The vascular bundles of G. acreana were classified as type V, characterized by a central vascular strand surrounded by condensed sclerenchyma sheaths and fiber cords. Conclusions: This study enhances the anatomical understanding of G. acreana and highlights its potential applications in reforestation, construction, furniture making, and pulp and paper production. Future research should focus on the mechanical properties and chemical composition of this species to improve its industrial utility.

ABSTRACT Background: The argan tree [Argania spinosa (L.) Skeels], native to Morocco, faces significant threats from climate change, leading to a shrinking natural distribution area. This study aimed to assess the diversity within argan tree populations and identify morphological differences and similarities among them by examining their fruits, seeds, and almonds. Results: Researchers analyzed 32 morphological characteristics from 13 populations (40 samples each, totaling 520 materials) across diverse Moroccan coastal and inland habitats. Analysis of variance and multiple tests revealed significant morphological changes and high diversity among the populations. Notably, Cluster Analysis showed that the Aoulouz population formed a distinct group, highlighting its unique characteristics. Significant differences were also observed in fruit, seed, and almond diversity parameters. Conclusion: The study confirms the high diversity of argan populations in Morocco’s natural distribution areas. These findings are crucial for developing integrated in situ and ex situ conservation strategies for the argan species. The research outputs will support the economic viability, ecological integrity, and long-term sustainability of this valuable and long-degraded species.

ABSTRACT Background: Arbuscular mycorrhizal fungi (AMF) generate a symbiotic relationship with most terrestrial plants, influencing the dynamics and functioning of ecosystems. There are few studies on the diversity of these fungi associated with forest species and in different types of ecosystems. The objective of this study was to characterize the diversity and structure of AMF communities associated with Cordia alliodora and Swietenia macrophylla in two forestry ecosystems with different types of management in Costa Rica. For this purpose, rhizosphere and soil samples were collected from 10 trees at random, spores and sporocarps were isolated and characterized, AMF abundance, richness and diversity were determined, and a physicochemical analysis of the soil was carried out. Results: Fifty-seven AMF morphospecies belonging to five orders, 10 families and 15 genera were identified, with a predominance of Diversisporales and Glomerales; we report 15 new geographic records of AMF increasing the richness to 76 species and by 24% the Glomeromycota’s richness in Costa Rica. There were no significant differences in total spore abundance between the two forest species, however, there were significant differences in the modes of formation and species composition. Conclusions: The alpha diversity analysis showed that rare species largely explain the differences between the sites, and the AMF community structure was influenced by edaphic factors such as pH and available phosphorus content. These types of studies highlight the importance of considering the identity and diversity of AMF associated with forest species of commercial interest and ecological importance in different types of ecosystems.

Background: The production of cellulose microfibrils/nanofibrils (CMF/CNF) has attracted increasing attention in recent decades due to their excellent barrier, mechanical, and surface chemistry properties. However, large-scale industrial production of CMF/CNF has been a major challenge due to their high energy consumption, limiting their application. In this context, in recent years many studies have focused on developing pre-treatments designed to facilitate the fibrillation of CMF/CNF by reducing energy consumption during their production. This review highlights the latest advances in the use of silicates as chemical pre-treatments for CMF/CNF production, covering the main aspects related to the effects of chemical modification on the production and the properties of materials for application in biodegradable packaging. Results: Energy consumption reductions of up to 30% were achieved by pretreating cellulose pulps using silicates. In addition, the pre-treatments resulted in smaller CMF/CNF diameters and greater individualization of the nanofibrils. Studies evaluating the thermal stability, hydrophobicity, mechanical properties, and porosity of CMF/CNF pre-treated with silicates have reported promising results. The application of CMF/CNF pretreated with calcium and magnesium silicates in cardboard coating resulted in packaging with low water vapor permeability and high ductility. Conclusion: Silicates interact well with cellulose surfaces, making them a promising material for the chemical pre-treatment of CMF/CNF. Furthermore, the modification by silicates could be an interesting strategy for expanding the use of CMF/CNF in the development of new products.

Background: Today, the biggest threat to mammalian predators with wide distribution areas is habitats fragmentation or changing climate conditions. We aimed to reveal the habitat suitability modeling and mapping of the Brown bear, which is an important large mammal in Turkey's borders, under change climate. The habitat suitability modelling was determined using the present (2010) and future (2040-2070-2100) chelsa climate scenarios (IPSL-CM6A-LR SSP126-SSP370-SSP585) Maxent method with the present data obtained by examining all studies on Brown bear. Then, the mapping result values for the different years and scenarios were classified as 0.5 unsuitable habitats, 0.51-0.8 suitable habitats and 0.81-1.0 most suitable habitats. Results: We determined that the variables contributing to the habitat suitability model of Brown bear are annual precipitation amount, the average annual air temperature, the precipitation amount of the wettest month, the ruggedness and elevation. According to the mapping results for different years and scenarios; Brown bear have suitable habitat a minimum of 14.87% of the study area in today, 12.56% in 2040 year, 10.93% in 2070 year and 8.24% in 2100 year. According to the SSP585 climate scenario of 2100 year, the habitat suitability of the Brown bear decreases by approximately 45%. Also, the climate envelope model created with MaxEnt revealed, the change climate in the 2100 year endangered the Brown bear. Conclusion: Therefore, these results will be a source of information for the sustainability of the extinction of the Brown bear, for the pre-protection of existing and potential habitats and for reducing the impact of change climate conditions.

Background: The macauba (Acrocomia aculeata (Jacq.) Lodd. ex Mart.) is a palm tree native to tropical regions and occurs in much of the Brazilian territory. Current studies are focused on the extraction and exploitation of vegetable oil from this fruit. However, there are few studies on the residue, the endocarp, which represents approximately 25% of the total mass of the fruit. Studies that search for solutions for using residue, thus adding value, and generating environmentally friendly products, are of fundamental importance. Thus, this research aimed to evaluate the physical and mechanical properties of reconstituted wood panels produced with different proportions of macauba endocarp particles to replace pine wood particles, in addition to characterize the physical and chemical properties of macauba endocarp. The chemical characterization tests were performed according to applicable standards. The basic density was determined according to the NBR 11941 standard. Thermogravimetric analysis (TGA), X-ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FTIR) were also performed. The particleboards panels were produced with a nominal density of 0.70g/cm³ and dimensions of 25x25x1.5cm. Five different treatments were evaluated with variations in the proportion of macauba endocarp particles in the core of the panel. For particle agglutination, phenol-formaldehyde adhesive was used at a proportion of 9% for the core and 12% for the faces, based on the dry mass of each panel. Scanning electron microscopy (SEM) was used to analyze the panel surfaces. Results: The endocarp of Acrocomia aculeata has low extractive content, high lignin content and high densification, 1.23g/cm³, when compared to Pinus oocarpa wood, 0.43g/cm³. All panels were classified as low density according to CS 236-66 and had an average apparent density between treatments of 0.586g/cm³. A greater dimensional stability and a decrease in the static bending properties of the panels was observed as the proportion of macauba endocarp particles increased. The internal bonding of the panels showed a positive result with the increase in the use of particles of the residue. Conclusion: The panels produced have potential for use for non-structural purposes.

Background: Acacia mearnsii and Eucalyptus dunnii are species planted mainly for tannin and cellulose production.However, its woods have characteristics favorable to their use for energy generation, being commercialized in the form of firewood, chips or charcoal too.Biochar is a stable form of carbon that can be obtained by converting small particles of wood in the pyrolysis process and that can be used as solid fuel, among other applications as a soil conditioner.In this study, the properties of biochar produced in a horizontal reactor using wood of these species and under milder temperatures were evaluated.Results: Temperature of 350 o C and the reaction time of 30 minutes promoted an increase in higher calorific value of 33% for A. mearnsii and 51% for E. dunnii, with gravimetric yield of 39% and 32%, respectively.it was found that the 250 and 300 o C was not efficient to carbonize the wood of both species.An increase in specific surface area is observed with increasing carbonization temperature.Bigger increases were produced at temperatures of 350 o C for E. dunnii and 420 o C for A. mearnsii, with increase in porosity.At these temperatures, there was an increase in surface area and a decrease in pore size. Conclusion:In temperatures of 350 o C, the woods of both species provided a good quality biochar with porosity, surface area, pore size and pyrolysis yield suitable for energy use.For soil conditioning use, considering these aspects, suggested to test the appropriate temperatures for each species, between 350 and 420 o C.

Background: The objective of this study was to evaluate the quality indicators for wood and charcoal from the Eucalyptus urophylla x Eucalyptus grandis hybrid (Clone GG 100) in different planting spacings. The study was conducted with the hybrid using the spacings of 2×1, 2×2, 3×2, and 3×3 m. The chemical properties of wood and charcoal were analyzed, and dry wood mass and energy per hectare were estimated. The data were subjected to the t test for comparison of means. Moreover, principal component analysis was conducted to assess the relationships between wood and charcoal indicators as a function of spacing. Results: The 2×2 m spacing showed the highest values for dry wood mass, lignin mass, mass of charcoal, and energy. The wider spacings of 3×2 and 3×3 m resulted in wood and charcoal of increased quality by showing wood of greater resistance to thermal degradation and charcoal of higher yield. Conclusion: Spacing between trees influenced wood quality indicators. The 2×2 m spacing showed higher estimates of mass and energy per hectare. However, wide spacings with an area greater than 6 m2 are more suitable for charcoal production due to their superior wood properties, especially basic density and total lignin, which influence gravimetric yields and bulk density.

Background: The aim of this research was to investigate the efficiency of methods to overcome primary dormancy and biochemical processes associated with germination of Erythrina falcata Benth seeds. Seeds were submitted to dormancy overcoming treatments and the water uptake pattern was analysed. We then evaluated the activity of the antioxidant enzymes SOD, CAT, and APX, and quantified lipid peroxidation levels, hydrogen peroxide content and total protein content. The experiments were performed in a completely randomized design and the statistical analysis used was Scott-Knott test at 5% probability. Results: Mechanical scarification with sandpaper leads to approximately 94% of germination in E. falcata, while control non-scarified seeds show only approximately 37% of germination. Treatments with hot water led to high mortality in E. falcata seeds. Rapid water absorption was observed in the first 18 hours of imbition when the seeds were scarified with sandpaper, and radicle emergence was observed after 36 hours. During imbibition there was an increase of antioxidant enzyme activity and a decrease in lipid peroxidation and H2O2 production, suggesting an efficient mechanism for regulating imbibition damage. A decrease in the total protein content was observed during germination of E. falcata seeds. Conclusions: Mechanical scarification is an efficient method for breaking dormancy of E. falcata seeds. During germination of E. falcata seeds there is a reduction in the production of H2O2 and lipid peroxidation, and an increase in the activity of antioxidant enzymes. The total protein content decreased along the germination time.