ABSTRACT 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.

ABSTRACT Background: The invasive tree species threaten the domestic species of a region. However, they can be evaluated for wood industry when they were cut to decrease the population. This study studied a fast-growing deciduous tree species, tree-of-heaven (Ailanthus altissima), to determine the optimum drying schedules of lumbers from Turkey-grown individuals. Results: Optimum schedule was determined from different suggestions in literature and applied in a 1m3 capacity laboratory type-drying kiln on 39 lumber pieces with dimensions of 65x65x2000 mm. The drying time and quality were evaluated according to standards and different methods (e.g. prong test) from literature. Although the fast-growing species had some risks with having more juvenile wood ratio and lower density, it could be dried 65 to 10% moisture content with in as short as 10 days with moderate-protective drying quality. Conclusion: Relatively shorter drying time with high quality compared to similar species (e.g. ash) might contribute the economic sustainability of sawmills. Because the shorter drying cycles will save more energy for per volume and they may be more profitable with shorter sellable dried lumber cycles. On the other hand, although the species was fast-growing, medium density (574 kg/m3) characteristics might show the potential for being a good alternative for the wood industry.

ABSTRACT Background: The productivity of the coastal Zululand region, which was known as the South African breadbasket for fibre is declining. Climate-related changes are a significant factor contributing to this decline. The 3PG (Physiological Processes Predicting Growth) model was calibrated for E. grandis x E. urophylla hybrids planted in this region to quantify the effect of climate variation x site on their growth and survival. Monthly weather data for the ungauged plantations were estimated using the Random Forest (RF) supervised learning algorithm. A dataset consisting of 17 permanent sample plots (PSPs) and published parameter values for this hybrid in various regions of Brazil were utilized for parameter estimation. Using a parsimonious optimization approach, we developed a novel method called extended Root Mean Square Error (eRMSE) to select the optimal parameter set. Result: The new parameter set yielded accurate predictions for three key variables; quadratic stem diameter (R2 = 0.85, E = 0.73), mean height (R2 = 0.84, E = 0.78), and basal area (R2 = 0.87, E = 0.78). Model performance at 15 independent sites allowed the comparison with three other Brazilian parameter sets for stand volume prediction at a specific age. The optimized parameter set provided a satisfactory, albeit slightly overestimated stand volume (V (m3ha-1), R2 = 0.65, E = -0.32) at the validation sites. Conclusion: The 3PG model can be adapted with parameter set from another region to characterize the growth of E.grandis x E.urophylla stands in South Africa.

ABSTRACT Background: The wood heat treatment results in the partial degradation of its chemical constituents, mainly cellulose and hemicellulose, reducing the hygroscopicity of the material. This process improves the dimensional stability and resistance to biodeterioration and worsens the mechanical resistance. This work aimed to evaluate the effect of heat treatment on the physical, anatomical, chemical, and mechanical properties of Fraxinus excelsior wood. In untreated and heat-treated wood, the pH, buffering capacity, basic density, equilibrium moisture content, shrinkage, wood anatomy, thermogravimetric behavior, and chemistry by conventional and FTIR methods were determined. Results: Heat treated wood had lower pH (5.50), equilibrium moisture content (6.26%), shrinkage (7,29%), holocellulose contents (55,96%) and higher buffering capacity (0,479 mmol/L), extractives (8,25%), and lignin contents (35,78%). Heat treatment reduced the pH and increased the buffering capacity of the wood, reduced the holocellulose content, and increased the lignin content, leaving the wood less hygroscopic and reducing its volumetric and linear variation. The process did not change the basic density and fiber length, but it reduced their width, lumen diameter, and wall thickness. The FTIR analysis confirmed the degradation of holocellulose and division of aliphatic side chains in lignin. The maximum dredging range of untreated and heat-treated wood occurred at 350 ºC, and the heat-treated wood had a higher residual mass when subjected to 500 ºC. Conclusion: Heat-treated wood can be indicated for products used in external environments, such as floors, fences, coatings, door and window structures.

ABSTRACT Background: Determining the basic density of the wood is usually defined as a simple process, but it requires caution and the operator’s skill to avoid errors in the analysis. In addition, it involves sample preparation and time to saturate the wood until obtaining the dry sample mass. The development of alternative measurement techniques could reduce the time to obtain the results and provide reliable values. Therefore, this study aimed to develop multivariate models to estimate the basic density of native woods using near-infrared spectra (NIR). Basic densities were determined by the water immersion method, and the values were associated with NIR signatures. Spectra were directly collected on the wood transversal and radial faces with an integrating sphere. Partial least squares regression (PLS-R) was calibrated and validated to estimate basic density based on spectral signatures. Results: In the cross-validation and prediction of the models, the results were promising. The coefficients of determination varied from 0.87 to 0.93 with a standard error of 0.01 %. The partial least squares discriminant analysis (PLS-DA) efficiently classified the wood species. The ratio of performance to deviation obtained satisfactory values, a minimum of 2.81 and a maximum of 4.20. Conclusion: The statistical parameters of the models based on NIR spectra showed potential for density measurements in floors, furniture, and solid wood products.

ABSTRACT Background: The Amazon rainforest plays an essential role in sheltering global biodiversity and providing essential ecosystem services. However, the region has been threatened by increased rates of deforestation and degradation, which is often reported as the failure of the Brazilian conservation policy that could affect the image of agriculture Brazilian products abroad. In this sense, here we aimed to evaluate the foreign environmental perception of the region using data from social medias, to assess which are the main terms related to the region, how their importance varies over time and whether this perception tends to be more negative or positive. For this, we used data from posts made on Twitter® involving the term “Amazon rainforest” over 18 weeks using a data mining process. From these posts, we extracted the text, which went through steps of cleaning and organization, as well as crossing with additional databases (such as the sentiment dictionary). From the final data set, we first evaluated which are the main terms present in these posts and how their importance varied in the evaluated period. Next, we assess whether the terms cited are mainly negative or positive and how this sentiment varied over the monitoring period. Results: We found that the main terms are related to the environmental context such as “carbon”, “deforestation” and “fire” and that there is a relationship between their importance and the occurrence of fires in the region, which is positive with a temporal lag. In addition, we also found that the posts are, on average, composed of 68.47% of negative terms and that this sentiment predominates throughout the entire time series, being higher during the fire peaks in the region. Conclusion: Our results indicate that the environmental perception of the region presented in the posts in Twitter® is mainly negative, due to the degradation and fires observed over the last few years. We also discuss limitations of the approach and establish perspectives for future work.

ABSTRACT Background: Thallium (Tl), which is one of the most toxic and destructive heavy metals for human and environmental health, has a higher level of chronic and acute toxicity in comparison to many harmful elements (such as Pb, Hg, Cd, and As) in comparison to many harmful elements and is classified as one of 13 primary metal contaminants by the US EPA (United States Environmental Protection Agency) and in ATSDR’s primary pollutant list. Thus, monitoring the Tl pollution in the air and reducing the pollution are among the primary research subjects. The existing study aims to determine the species that are suitable for monitoring and reducing the Tl pollution in Düzce province, Türkiye, which is the fifth-most polluted province in Europe in terms of air pollution. This study analyzed the changes in Tl concentration in the samples (wood, outer and inner bark) taken from species grown in Düzce by species, organ, direction, and age groups in the last 40 years. Results: As an outcome, the uppermost Tl concentrations were found in the outer barks, and it is thought to be caused by air pollution. The outcomes achieved in the existing study revealed that the suitable species to be used in watching the Tl pollution in the air are Cupressus arizonica and Picea orientalis, whereas those to be used in reducing the Tl pollution are Pinus pinaster, Cedrus atlantica, Cupressus arizonica, and Pseudotsuga menziesii. Conclusions: Cupressus arizonica is a species that can be effectively used in both monitoring and decreasing Tl pollution.

ABSTRACT Background: This article aims to provide information on the diameter distribution of naturally regenerated forests of Taurus cedar (Cedrus libani A. Rich), a tree species endemic in the mountains of the Eastern Mediterranean basin and assess their prediction ability with the Johnson SB distribution. Previous research attested to the flexibility of Johnson family distributions to mimic empirical diameter data for a large set of tree species, justifying its use for the case study. A set of 134 plots (400 m2) were sampled in the most represented areas of the distribution of the species in Türkiye and diameter at breast height was measured in all the living trees. The cedar forests displayed heterogeneous diameter structures with diameters range from 10 to 116 cm and irregular shapes (e.g. unimodal, bell-shaped, left- and right-skewed, and non-uniform). Over three-quarters of the empirical diameter distributions (104 sample plots) were classified as SB distribution. The remaining were classified as bounded at the lower end, SL (16) or unbounded, SU (14). The authors essayed the 3-parameter and 4-parameter recovery methods after Parresol and Fonseca and other´s fundamental studies. The 3-parameter recovery method outperformed the 4-parameter method in the convergence criterion and error index (EI) expressed in the basal area. Results: Results show that the Johnson SB distribution can adequately reproduce the high variability in diameter for most of the distributions observed in these natural forests, providing reliable estimates which can serve as a basis for decision support systems. Conclusion: The SB distribution can represent the diameter distributions of natural cedar forests, even if the empirical distributions are not in the region covered by this distribution.

ABSTRACT Background: Climate change is a serious problem in forest ecosystems and it is required to manage forest stability, resilience, and vitality truly sustainable in future climatic conditions. Particularly trees are one of the crucial components in the forest ecosystem since they are exposed to climate change-induced range shifts during their growth and development. The present study, therefore, investigated how dendrometric, tree ring widths and anatomical variables of Scots pine and Sessile oak trees showed variations between managed and unmanaged forests. Results: Both Scots pine and Sessile oak trees indicated great variance in their dendrometric, tree ring width, and anatomical properties between managed and unmanaged forests. In this study, Scots pine showed taller trees in unmanaged forests, while Sessile oak forests did not show the difference in stem heights between managed and unmanaged forests. Stand characteristics revealed different patterns between managed and unmanaged forests; unmanaged forests revealed greater stand stability than managed forests for both Scots pine and Sessile oak trees. Managed forests of both Scots pine and Sessile oak trees indicated greater stem diameters than unmanaged forests. Dendrometric results also showed differences in managed and unmanaged forests since tree ring widths of Scots pine and Sessile oak trees had more than 1.5 times wider tree rings in managed forests than in unmanaged forests. Conclusion: In this study, managed forests of Scots pine and Sessile oak showed greater stand characteristics and dendrometric traits than unmanaged forests. It may be suggested that managed forests can ensure better growth and development environment for particularly Scots pine and Sessile oak trees.

ABSTRACT Background: Betula platyphylla Sukaczev is one of important tree species due to its ecological and economic value. It is a cold-tolerant tree species which also faces heat stress during summer. In the current study, RNA-Seq profiling of two-month-old B. platyphylla seedlings were conducted utilizing the MGISEQ-2000 platform. Results: In total, 856,347,961 clean reads were obtained from 26 RNA-Seq libraries. Totally, 822,552,820 reads were successfully mapped to B. platyphylla reference genome. Further, a total of 360 and 264 DEGs were discovered under cold and heat exposure, respectively, while a total of 104 DEGs were identified under both cold and heat exposure. It was found that several pathways including response to cold, response to heat, response to temperature stimulus, response to stress, lipid metabolic, jamonic acid and ethylene, even developmental processes were significantly enriched in GO enrichment analysis of cold and heat stress in biological process term. Several transcription factors (TFs), including MYB66, CBF2, bHLH96and bZIP7 take a pivotal role in response to temperature stresses. Furthermore, heat shock proteins were identified under cold and heat stress, respectively, suggesting these genes participate in reducing cold and heat stress detrimental effect by interacting with TFs or other genes related to abiotic stresses, chlorophyll and photosynthesis, osmoprotectants, and phytohormone as well. Conclusion: This study not only underlying B. platyphylla’s molecular mechanism in response to temperature stresses but also provides candidate genes involved in response to temperature stresses.

ABSTRACT Background: Heavy metal contamination in the air has been gaining importance from scientists due to increasing industrial activities, population growth, and density in urban areas causing many crucial environmental pollution problems. Heavy metals do not quickly disappear and do not decay in nature; they accumulate in plant organs and indirectly affect human and environmental health. On the other hand, some elements are essential for plant growth, but some have poisonous or carcinogenic consequences, even at small concentrations. Thus, determining and observing heavy metal concentrations in the atmosphere is crucial., Plants are the utmost important indicator of heavy metal concentration changes in the air and are called biomonitors. The current study aims to determine the variation in some elements (K, P, Fe, Zn, Cu, Cd, and Cr) concentration inPicea pungensEngelm. (valued for its bluish or silvery-gray foliage) grown in the Ankara city center (capital of Türkiye and second crowded city), based on the plant needles and the age of the branch. Thus, this study tried to determine the potential of using needle leaves and branches ofP. pungens as a biomonitorto determine some heavy metal concentrations. Results: The heavy metal concentrations significantly differed by organ and organ age. The element levels were higher in the branches in some years and the needles in some years. Conclusions: This result indicates that Picea pungens needles and branches are suitable for observing studied heavy metal concentrations. Using branches and needles does not also harm the plant species.

ABSTRACT Background: Tropical Dry Forests (TDFs) are repositories of biodiversity, ecosystem services and carbon that are threatened by fragmentation and climate change. Floristic and phytosociological studies are fundamental database for many studies of conservation and sustainability, but there is a knowledge gap concerning TDFs, especially in the Andes valleys. The aim of this study was to determine the phytosociological structure and composition of woody vegetation of seven TDFs in the Colombian Andes, and because the flora associated with this type of forest has a geographical distribution restricted to each locality where this biome exists, provide information on the main species, genera and families for conservation and restoration actions as well as for future meta-analyses. We sampled seven TDFs with 20 plots of 25 m × 4 m. Results: In the 1.88 hectares of samples, 8422 individuals were surveyed, distributed in 170 species, 120 genera and 50 botanical families. Of these species, 78.82% were identified at the species level, 17.05% at the genus level, and 4.11% at the family level. The most important families were Fabaceae and Myrtaceae. Nitrogen-fixing Fabaceae species were prominent amongst the important species, especially in low altitude and more stressing sites. Conclusion: The structure, composition and ecological importance of these forests must be considered for conservation and ecological restoration plans, in particular the habitat preference of species along the topographic gradient. Particularly noteworthy for conservation are the Myrtaceae species because promote connectivity and regeneration by providing resources for the fauna, a driver of dispersal, as well as nitrogen-fixing Fabaceae species, because promote the resilience and natural regeneration of TDFs in the Andes, a key feature of stability.

ABSTRACT Background: Patauá (Oenocarpus bataua Mart.) is a palm tree belonging to the botanical family Arecaceae that occurs throughout the Amazon. Like açaí, an edible pulp is extracted from its fruits, remaining a fiber-rich waste. Revealing the potential of such raw or thermochemically modified fibers for producing bioproducts is a novelty in the literature. Therefore, this work aimed to characterize patauá fibers in natural and alkali-treated conditions to support future bioproduct applications. Alkaline treatments were performed under mechanical stirring combining two NaOH levels (5 and 10%) and two temperatures (80 and 100°C). Morphological characterization was performed by light microscopy and scanning electron microscopy (SEM). The contents of the structural and non-structural chemical components were determined, and chemical groups were evaluated by Fourier-transform infrared spectroscopy (FTIR). The physical characterization included moisture content, apparent density, and water absorption tests. Results: The macerate revealed short fibers with typical elongated morphology, mean cell wall thickness (4.10 µm) greater than the mean lumen width (3.01 µm), and mean length of 445 µm. The alkaline treatments partially individualized the fibers from bundles, cleaned extractives from the surface, and unblocked superficial pits by removing silica-rich structures. They substantially removed non-cellulosic components, but FTIR showed condensed lignin exposed on the fiber surface. Density and water uptake increased concerning natural fibers. Patauá’s short length and susceptibility to modification through thermochemical treatments that concentrated cellulose up to 50% indicated great potential for developing composites and nanofibers. Regardless of the NaOH content, 100°C was more efficient in concentrating cellulose. Conclusion: Patauá fibers have unique natural characteristics. They occur as flatted fiber bundles, have silicon-rich structures obstructing their superficial pits, and comprise more lignin than cellulose.

ABSTRACT Background: Managed Caatinga forests in Northeast Brazil are an important source of wood products, however, successful regeneration and regrowth is important to guarantee sustainability in these forests. The main objective of this study was to evaluate the natural regeneration and forest regrowth ability of a Caatinga forest under varying clear-cut treatments, as well as to estimate the recovery time of stand parameters. Results: An experiment was set up in Petrolina, Pernambuco state, Brazil, comparing five clear-cut strip widths: 0, 40, 60, 80 and 100 meters. Forest inventory data was gathered before and eight years after harvesting in 19 plots of 10 x 40 m. Tree seedling regeneration (individuals with circumference at breast height < 6 cm and minimum height of 0.5 m) was also monitored in 5 x 5 m sub plots, before harvesting, one, three and eight years after harvesting. Conclusions: No influence of the clear-cut strip width on regeneration and forest regrowth ability was detected, with all treatments presenting similar growth and tree species diversity and similarity values. The estimated growth rates of the clear-cut plots were of 0.12 m2·ha-1·year-1 and 0.39 m3·ha-1·year-1 for basal area and volume, respectively, resulting in recovery times of 35 and 49 years, longer than the 15 years cycles generally adopted in Caatinga forest management plans.

ABSTRACT Background: This study aimed to evaluate UAV images of Pinus taeda L. stands for classifying trees attacked by Sapajus nigritus in Southern Brazil. UAV images were acquired on March 2018, using a DJI Phantom Pro 4 over 18.73 hectares. We evaluated different band compositions and vegetation indices. Using photo interpretation based on the color of the crown and field measurements, the trees were manually labeled as not attacked, dead, and attacked. The classified trees were divided into training (75%) and validation (25%), considering three tree crown diameters (0.5, 1, and 1.5 m) and three region-oriented classification algorithms. The classification accuracy was assessed by overall accuracy and the kappa index. Results: A total of 3,773 trees were manually detected, of which 39% were attacked, 5% died and 56% were not attacked. The results also indicated that the best-chosen diameter was 0.5 meters, the best classifier algorithm was the SVM, and the highest accuracy was represented by the composition of the ExG index associated with the original spectral bands. Conclusion: We argue that the attacks can be monitored using UAV images and such results provide insights for forest management initiatives.