CERNE 2022-05-31T13:54:39+00:00 Lucas Rezende Gomide Open Journal Systems <p>Cerne is a journal edited by the Federal University of Lavras, Minas Gerais state, Brazil, which quarterly publishes original articles that represent relevant contribution to Forestry Science development (Forest ecology, Forest Management, Silviculture, Technology of Forest Products).</p> <p>Submitted manuscripts must be written in English, be original, and be in accordance with the journal's standards and not be submitted for publication elsewhere. Its content (data, ideas, opinions and concepts) is the sole responsibility of the author(s). When necessary, it must be attested that the research in question was approved by the Ethics and Biosafety Committee of the institution to which the author responsible for the manuscript submission is linked to.</p> <p>By submitting the article, the authors agree that the copyright of the same is automatically transferred to the Journal Cerne. Authors can use the article after publication, without the prior permission of Cerne, as long as publication credit is given to the Journal.</p> ASSESSMENT OF ALTERNATIVE FOREST ROAD ROUTES AND LANDSLIDE SUSCEPTIBILITY MAPPING USING MACHINE LEARNING 2021-10-07T15:31:44+00:00 Ender Buğday Abdullah Emin AKAY <p><strong>Background:</strong> Forest roads are among the most basic infrastructure used for forestry activities and<br />services. To facilitate the increased amount of biomass harvesting adequately, the existing road network<br />may require modifications to allow forest transportation within harvesting units that are not yet accessed<br />by the roads. The construction of a forest road can trigger landslides, so the necessary constraints should<br />be considered when the road is being planned to preclude such problems. Landslide Susceptibility<br />Mapping (LSM) has become an integral part of the growing process of machine learning (ML), providing<br />a more effective platform for practitioners, planners, and decision-makers. This study aims to reveal the<br />most suitable alternative routes for a forest road, especially in areas susceptible to landslides, and to<br />provide an effective tool for decision-makers.<br /><strong>Results:</strong> For this purpose, two models were developed through ML: Logistic Regression (LR) and<br />Random Forest (RF). Elevation, slope, aspect, curvature, Topographic Wetness Index (TWI), Stream Power<br />Index (SPI), distance from the fault, the road, and the stream, and lithology were considered as the main<br />landslide susceptibility factors in these models. The best model was obtained by the RF approach with<br />an Area Under ROC Curve (AUC) value of 81.9%, while the LR model was 78.2%. LSM data was used as<br />a base, and alternative routes were obtained through CostPath analysis.<br /><strong>Conclusion:</strong> It has been shown that the ML methods used in this study can positively contribute to<br />decision-making by providing more effective LSM calculations in studies to determine alternative routes<br />in a forest road network.</p> 2022-08-03T00:00:00+00:00 Copyright (c) 2022 STAND-LEVEL BIOMASS ESTIMATION FOR KOREAN PINE PLANTATIONS BASED ON FOUR ADDITIVE METHODS IN HEILONGJIANG PROVINCE, NORTHEAST CHINA 2022-02-15T14:49:01+00:00 Shidong Xin Surya Bagus Mahardika Lichun Jiang <p><strong>Background:</strong> Korean pine (<em>Pinus koraiensis</em> Siebold &amp; Zucc.) is one of the primary plantation conifer<br />species of economic and ecological importance in northeast China. Forest biomass estimation in the<br />broader landscape has been receiving attention from researchers and forest managers. The development<br />of forest stand biomass models is regarded an effective method to estimate forest biomass at large<br />scales. This study was carried out for developing stand-level biomass models for Korean pine plantations.<br />Four additive methods were compared: Aggregation 1, Aggregation 2, Adjustment, and Disaggregation.<br />All the stand biomass additive modeling systems (i.e., total, root, stem, branch, and leaf) included both<br />stand volume and biomass conversion and expansion factors (BCEFs) as predictors.<br /><strong>Results:</strong> The predictive performance of the four additive methods and Constant BCEFs were ranked<br />as follows: Aggregation 1 &gt; Disaggregation &gt; Adjustment &gt; Aggregation 2 &gt; Constant BCEFs. The<br />prediction accuracy of the four additive methods was not consistent across the stand volume intervals.<br /><strong>Conclusion:</strong> The model based on the Aggregation 1 method was recommended for predicting stand<br />biomass. However, different additive method should be selected according to the stand volume intervals<br />of the Korean pine plantations.</p> 2022-08-03T00:00:00+00:00 Copyright (c) 2022 EUCALYPTUS BREEDING PROGRAMS: A PROPOSAL FOR THE USE OF INBRED PROGENIES 2022-04-26T17:48:28+00:00 Magno Antonio Patto Ramalho Heloisa Guimarães Santos Thaise Da Silva Souza <p><strong>Background:</strong> This review aims to discuss alternatives for obtaining new clones of eucalyptus (<em>Eucalyptus</em><br /><em>spp.</em>) with greater efficiency than current methods, as well as the feasibility of obtaining hybrid seeds.<br />The commercial-scale use of eucalyptus hybrid seeds may reduce implantation costs and bring other<br />advantages for forest exploitation. The proposal focuses on using inbred progenies (S<sub>1</sub>, S<sub>2</sub>...S<sub>g</sub>) to improve<br />the species. Self-fertilization releases a greater proportion of undesirable alleles hidden in heterozygotes,<br />increasing selection success.</p> <p><br /><strong>Results:</strong> From the best individuals of the inbred progenies, full-sibs (FS) progenies will be developed,<br />allowing the selection of new clones and conduct recurrent selection programs. The hybrid seeds must<br />be obtained, also from the FS evaluations, in each selfing generation (S<sub>g</sub> x S<sub>g</sub>). Simultaneously with<br />the conduction of inbreeding generations, information must be gathered aiming to implement the<br />strategy for obtaining hybrid seeds, such as verifying the feasibility of generating double haploid lines<br />and looking for alternatives to facilitate the large-scale production of hybrid seeds.</p> <p><br /><strong>Conclusion:</strong> This review of research results can serve as an initial basis for obtaining new clones of<br />eucalyptus with greater efficiency than current methods, as well as the feasibility of obtaining hybrid<br />seeds.</p> <p> </p> 2022-08-05T00:00:00+00:00 Copyright (c) 2022 EFFECTS OF PLANTING SPACING ON BIOMASS ACCUMULATION, CHEMICAL, PHYSICAL AND ENERGETIC PROPERTIES IN A PLANTATION OF Eucalyptus tereticornis SM. IN COSTA RICA 2021-10-28T16:42:44+00:00 Juan Carlos Valverde Daoberto Arias Rooel Campos Luis Diego Jimenez Jean Pierre Morales <p>Background: The use of tree plantations for energy purposes has shown an increase in their use in tropical regions due to the rapid growth of the species and low cost of energy generation. This has led to the development of optimization studies of crop conditions in the last decade to generate high levels of biomass in the shortest possible time. However, the determination of the effect of spacing on physical, chemical and energy properties has not been clear for <em>Eucalyptus tereticornis</em>, which limits the development of plantations with optimal silvicultural conditions.</p> <p>Results: The results showed that mortality ranged from 29 to 69 %, being the 1.0x2.0 m spacing the one that presented better yields with significantly higher diameter and height (9.13 cm and 14.17 m respectively) with a higher biomass accumulation (140.04 ton ha<sup>-1 </sup>without treetop) concentrated mainly in the stem. The other two spacings presented statistically lower and non-significant values. On a chemical level, differences were only found in N, C and C/N ratio, being 1.0x2.0 m the spacing that showed significant values. With energetic properties, again the 1.0x2.0 m spacing showed higher calorific value, but also higher ash and volatile content.</p> <p>Conclusions: The spacing of 1.0x2.0 m was the one that showed significant values in most of the variables, being the optimal spacing for the establishment of the species in the environmental conditions of the study.</p> 2022-08-05T00:00:00+00:00 Copyright (c) 2022 NEAR INFRARED SPECTROSCOPY FOR ESTIMATING PROPERTIES OF KRAFT PAPER REINFORCED WITH CELLULOSE NANOFIBRILS 2021-09-15T10:42:19+00:00 Lidiane Costa Lima Lívia Ribeiro Costa Ana Márcia Macedo Ladeira Carvalho Maria Lucia Bianchi Paulo Ricardo Gherardi Hein <p><strong>Background:</strong> The aim of this study was to investigate near infrared (NIR) spectroscopy ability to estimate nanofibril concentration, physical and mechanical properties of Kraft paper reinforced with cellulose nanofibrils (CNF).</p> <p><strong>Results:</strong> principal component analysis (PCA) revealed no separation among specimens related to nanofibril content. Partial least squares regression (PLS-R) models for estimating nanofibril content, tensile index, stretch and resistance to air passage yielded R²cv ranging from 0.73 to 0.98. Partial least squares - discriminant analysis (PLS-DA) correctly classified up to 93% of the paper specimens both by grammage and nanofibril content using NIR spectra.</p> <p><strong>Conclusion:</strong> this approach appears to be suitable for predicting physical and mechanical properties of Kraft papers and can detect cellulose nanofibril content in the paper matrix.</p> 2022-08-03T00:00:00+00:00 Copyright (c) 2022 PHYLOGENETIC RELATEDNESS AND COMPETITION: A POT EXPERIMENT WITH SEMIARID TREE SPECIES 2022-04-08T10:29:15+00:00 Maria Taiane Tavares Bruno Cruz de Souza Bruno Sousa Menezes Francisca Soares Araújo Júlia Sfair Roberta Zandavalli <p><strong>Background:</strong> Factors determining coexistence of the species have been recognized out since Darwin, but empirical studies have brought the relationship between niche similarity and competition into question. Knowing the mechanisms of coexistence makes it possible to predict biological invasions and determine better species combinations for the restoration and recovery of degraded areas. This study aimed to test the competition-relatedness hypothesis for semiarid tree species. Thus, an experiment was carried out with a phylogenetic gradient of tree species, planted in pairs. The phylogenetically closest pair consisted of congeneric species of the same clade, the intermediate pair comprised congeneric species of distinct clades, and the more distant pair were species of the same family.</p> <p><strong>Results:</strong> Our results show that the phylogenetically closest and the more distant pairs corroborated the competition-relatedness hypothesis, but the presence of one species with high competitive ability in the intermediate pair caused an unexpected pattern.</p> <p><strong>Conclusion:</strong> Niche differences are important for coexistence, but it is necessary to know the competitive ability of each species and the specific associations that are more productive to improve the efficiency of restoration programs and to reveal the degree of aggressiveness in the case of invasive species.</p> 2022-08-05T00:00:00+00:00 Copyright (c) 2022 THE WETTABILITY OF BORON AND OIL TREATED BEECH AND SCOTS PINE WOOD 2022-02-11T11:41:58+00:00 Eylem D. Tomak <p><strong>Background: </strong>Nowadays, demands for more environmentally friendly and cost effective preservatives are increasing, and new non-traditional procedures are being explored in wood protection field. Plant oils improve the dimensional stability, water repellency and equilibrium moisture content of wood, and protects wood against decay fungi by means of its hydrophobic properties. The aim of this study is to investigate the influence of heat treatment and oil impregnation with or without prior treatment with boron compounds on wetting characteristic of wood. Wood specimens were impregnated with boric acid, borax and agricultural boron at concentrations of 1%, 2% and 5% followed by oil heat treated with waste and sunflower oil at 160ºC. Wettability was measured by contact angle with the sessile drop technique using water.</p> <p><strong>Results:</strong> Water contact angles on oil treated specimens increased while wetting tension decreased, and the wood more poorly wetted by water compared to the controls. A change in the drop volume on the surface of double treated specimens was around 5% based on the initial drop volume. Waste oil treatment resulted in having the greatest water repellent efficiency. High loadings of boron compounds decreased the contact angle and therefore the quantity of water absorbed by the wood increased.</p> <p><strong>Conclusion: </strong>Wettability was decreased in specimens pretreated with boron and this confirmed that the hydrophobic surface was created by oil. Wettability is a prerequisite for good adhesion, coating and painting and this attribute may be reduced by the less hydrophilic surfaces created after oil heat treatment.</p> 2022-08-03T00:00:00+00:00 Copyright (c) 2022 DESICCATION TOLERANCE AND GERMINATION OF Psidium guajava SEEDS FROM DIFFERENT REGIONS OF BRAZIL 2022-01-06T11:31:48+00:00 Alana Chocorosqui Fernandes Olívia Alvina Oliveira Tonetti Anderson Cleiton José José Marcio Rocha Faria <p><strong>Background:</strong> The germination ecology of <em>P. guajava</em> seeds collected in two regions of Brazil was investigated aiming to (1) characterize the seed batches; (2) determine the best temperature for germination; and (3) assess variations in seed desiccation tolerance (DT). For each batch, we determined seed water content and initial germination. To evaluate temperature effects, we tested seed germination. After, we generated the imbibition curves for the two provenance. To evaluate the loss of DT, the seeds were left to germinate along different time intervals. We monitored water loss by regularly weighing the seeds until achieving stabilization, keeping them under these conditions for 72 hours. After drying, the seeds were pre-hydrated and submitted to the germination test. <strong>Results:</strong> We identified variations in physiological characteristics between the seeds from north and southeast batches. At the temperature extremes, the seeds from both provenance failed to germinate. The highest germination percentages were observed at 20 and 25 °C (constant) and between 20-30 °C (alternating) for the two batches and, for the southeast batch specifically, at 30 °C. The imbibition curve displayed a triphasic pattern with a rapid increase in seed fresh weight in the first 48 hours.</p> <p><strong>Conclusion:</strong> The southeast provenance seeds lost DT abruptly, until its complete loss after radicle protrusion, which occurred in both batches. The highest values of germination speed index (GSI) of both provenance were observed after a 9-day imbibition period, suggesting seed hydration memory. Drying resulted in necrosis of the root tissue and death of the seeds with visible roots.</p> 2022-04-01T00:00:00+00:00 Copyright (c) 2022 DOES THE FAXINAL SYSTEM HELP TO MAINTAIN THE GENETIC DIVERSITY OF Curitiba prismatica (D. Landland) Salywon & Landrum? 2022-01-06T11:27:35+00:00 Richeliel Albert Rodrigues Silva Fábio de Almeida Vieira Evandro Vagner Tambarussi Kyvia Pontes Teixeira das Chagas Chagas Luciano Farinha Watzlawick Henrique Soares Koehler <p><strong>Background:</strong></p> <p><em>Curitiba prismatica</em>, popularly known as murta, is a forest species endemic to the Mixed Ombrophilous Forest and predominant in the Faxinal traditional agricultural system. The present study aimed to select molecular markers and assess whether the Faxinal System contributes to the maintenance of the genetic diversity of the species, thus helping to inform its management and conservation. As such, 120 adult reproductive individuals were sampled, 60 in two areas managed in the Faxinal System, and 60 in two conservation areas.</p> <p><strong>Results:</strong></p> <p>From an initial selection of 30 markers, eight ISSR markers were used which resulted in 67 polymorphic loci. The results show that the average diversity within populations is 80.54%. The Shannon (<em>I</em>) and Nei’s (<em>He</em>) diversity indices were 0.53 and 0.36, respectively. According to Nei's genetic identity, the populations form two groups, one consisting of the Faxinal populations and the other consisting of the populations in the conservation areas. This is consistent with the analysis of the genetic structure of the populations which indicated the existence of two distinct genetic groups (<em>K</em> = 2).</p> <p><strong>Conclusion:</strong></p> <p>Thus, based on molecular data, the populations in the Faxinal System had higher rates of genetic diversity, despite constant human activity within the system. Therefore, the Faxinal System contributes to the conservation of <em>C. prismatica </em>genetic diversity; however, considering the economic potential of the species and to minimize impacts on the existing fragments, there is a need to work with the local population to ensure sustainable forest management of the species.</p> 2022-01-27T00:00:00+00:00 Copyright (c) 2022 GENETIC CHARACTERIZATION OF REMAINING POPULATIONS OF Paratecoma peroba, AN ENDANGERED AND ENDEMIC SPECIES OF THE ATLANTIC FOREST 2022-04-04T14:04:43+00:00 Tábatta Caroline Cerri França Leticia Rigo Tavares Adelson Lemes da Silva Júnior Fábio Demolinari de Miranda Lucas Batista Vargas Karla Maria Pedra de Abreu Marcos Vinicius Winckler Caldeira <p><strong>Background:</strong> The objective of this study was the genetic characterization of remaining populations of<br />the species Paratecoma peroba occurring in fragments of the Atlantic Forest, by estimating parameters<br />of diversity and genetic structure. The study was carried out in two forest fragments, the Atlantic Forest<br />Environmental Education Pole (area 1) and the Pacotuba National Forest (area 2), where 93 adult trees<br />were identified.<br /><strong>Results:</strong> Ten Inter Simple Sequence Repeats (ISSR) primers were used in genotyping, obtaining 112<br />amplified bands with 87.5% polymorphism. The genetic diversity estimated for the populations from the<br />Nei (H*) and Shannon (I*) indices was higher for area 1. For the joint data, moderate genetic diversity<br />was observed, referring to the average values of 0.26 and 0.40, obtained for the H* and I* indices,<br />respectively. Molecular variance analysis resulted in moderate differentiation between populations (ΦST<br />= 0.143), while gene flow analysis (N m = 6.69) revealed the occurrence of similar alleles between them.<br />However, the predominance of a single genetic group in area 2, revealed from Bayesian approach,<br />indicates that its genetic structure, possibly generated by the current scenario of fragmentation of the<br />Atlantic Forest and the distancing of populations, affecting the contemporary gene flow.<br /><strong>Conclusion:</strong> Despite the moderate genetic diversity of the species for the area 2 population, actions<br />toward inclusion of seedlings obtained from seeds from neighboring fragments, including area 1, and the<br />increase in the connectivity of forest fragments through ecological corridors, could assist in augmenting<br />its genetic variation.</p> 2022-08-03T00:00:00+00:00 Copyright (c) 2022 PINE AFFORESTATION IMPROVES THE BIOLOGICAL SOIL ATTRIBUTES LINKED TO METHANE OXIDATION IN A TEMPERATE ZONE OF ARGENTINA 2021-11-09T15:11:59+00:00 Ezequiel Jusus Teran María Eugenia Priano María Paula Juliarena María Elena Fernández Javier Enrique Gyenge <p><strong>Background: </strong>Atmospheric methane (CH<sub>4</sub>) is responsible for approximately 20% of global warming since the preindustrial era. Forests are land ecosystems whose role is crucial for mitigating the greenhouse effect due to their capacity to capture and store C and preserve other processes such as CH<sub>4</sub> oxidation in the soil. On the other hand, there are contradictory results about the magnitude of CH<sub>4</sub> uptake in afforestation. This land conversion implies changes in microenvironmental conditions and modifications in vegetation tissue chemistry entering the soil, with changes in soil life forms.</p> <p><strong>Results: </strong>The averaged potential CH<sub>4</sub> oxidation rate in the laboratory (MOL) of afforested soil was 186% greater than that of the grassland, which could be marginally attributed to differences in soil physicochemical parameters like bulk density, pH and organic matter. MOL’s seasonal pattern was observed at both plots, with the highest values at the warm and rainy season. MOL magnitude increased with soil depth up to 10-15 cm, which corresponds with the mineral layer.</p> <p><strong>Conclusions:</strong> MOL were higher in afforested soils than in those covered by grasses. However, in spite of the differences, MOL followed similar patterns following the season’s climatic characteristics, showing their maximum MOL value at the same soil depth. Pine afforestation would improve the biological soil attributes linked to methane oxidising bacteria compared to the grassland systems.</p> 2022-08-03T00:00:00+00:00 Copyright (c) 2022 EFFECT OF ENVIRONMENTAL FACTORS ON THE FRUIT ESSENTIAL OILS OF Pistacia terebinthus L. GROWING WILD IN TURKEY 2021-09-27T14:23:03+00:00 Serkan Gülsoy <p><strong>Background:</strong> The aim of this study was to investigate the effect of environmental factors on the essential<br />oil yields (EOYs) and major essential oil components in the ripe fruits of Pistacia terebinthus L. (turpentine<br />tree), which is a medicinal and aromatic plant. Fruit samples were collected from 34 different locations<br />of the turpentine tree growing wild in the Lake District in the Mediterranean Region of Turkey. EOYs (%,<br />v/w) and essential oil component ratios (%) were determined in fruit samples by hydrodistillation and<br />GC-MS methods, respectively. The effect of environmental factors on these variables were analyzed<br />using Pearson Correlation and Principal Component Analysis.</p> <p><br /><strong>Results:</strong> The essential oil yield of fruits collected from different localities ranged from 0.05% (v/w)<br />to 0.19% (v/w). In terms of average values, α-pinene with 41.01% and limonene with 14.28% were the<br />major components in the essential oils of ripe fruits. Among the environmental variables, longitude<br />and sand % in 10-30 cm were the variables that made a statistically significant difference (p &lt; 0.05)<br />in fruit essential oil yield. According to the results of principal components analysis (PCA), α-pinene<br />and Ocimene components were most affected by silt (%, 10-30 cm) and pH (%, 30-50 cm) ratios. The<br />longitude and total annual precipitation (mm) were the most determining variables in the sabinene and<br />limonene components, respectively. It was seen that the total lime ratios at different depth levels of the<br />soils taken from the localities were the most effective variables for Myrcene and p-Cymene components.</p> <p><br /><strong>Conclusion</strong>: The study findings showed that EOYs and intended volatile component ratios in ripe fruits<br />of turpentine trees grown under appropriate environmental conditions can be increased.</p> 2022-08-05T00:00:00+00:00 Copyright (c) 2022 SOCIO-ECONOMIC FACTORS INFLUENCING HOUSEHOLD DEPENDENCY ON FORESTS: AN EMPIRICAL EVIDENCE FROM TURKEY 2022-01-20T11:39:06+00:00 Üstüner Birben <p><strong>Background:</strong> Although forest villages in Turkey do not differ from other villages in the country<br />in terms of administrative divisions, the job possibilities of their residents are limited due to the<br />location of the villages in areas with rugged terrain. Forest villages have the poorest economic<br />status of all types of communities in the country in terms of per capita national income and socioeconomic<br />structure; limited agricultural land; inadequate transportation and infrastructure; and,<br />most importantly, weak educational, health, and cultural services.</p> <p><br /><strong>Results:</strong> This study explains forest dependency and its relation to certain characteristics of<br />householders by a case study. Data were collected from 150 households and were analyzed using<br />the logistic regression model.</p> <p><br /><strong>Conclusion:</strong> The results showed that a householder’s age, duration of residence, and employment<br />variables had a significant effect on the forest whereas other variables, gender, educational level,<br />and household size, did not have a statistically significant effect on forest dependence.</p> 2022-08-05T00:00:00+00:00 Copyright (c) 2022 HOW DO METEOROLOGICAL FACTORS ALTER THE PHENOLOGY OF A NEOTROPICAL TREE SPECIES? 2022-05-31T13:54:39+00:00 Thalles Luiz Negreiros da Costa Fernanda Moura Fonseca Lucas Bruna Rafaella Ferreira da Silva Kyvia Pontes Teixeira das Chagas Ageu da Silva Monteiro Freire João Gilberto Meza Ucella-Filho José Augusto da Silva Santana Malcon do Prado Costa <p><strong>Background:</strong> Neotropical species lack autecological information. Among these, are phenological studies, which help to understand forest dynamics and provide important contributions to the collection, restoration, and conservation programs. This research aimed to characterize the vegetative and reproductive phenological behavior of neotropical species <em>Geoffroea spinosa</em> Jacq. in a seasonally dry tropical forest, as well as to verify if there is a correlation between phenophases and environmental parameters. Twenty individuals were accompanied monthly for two years, to detect and tally the presence of floral buds, flowers, immature fruits, ripe fruits, leaf emergence, presence of mature leaves, and defoliation. A semi-quantitative evaluation was carried out with the Fournier method.</p> <p><strong>Results:</strong> The results showed that the population had synchrony of reproductive events, with more than 50% of the individuals blooming and fruiting during the same time interval. Furthermore, the circular statistical test indicated a high seasonality for reproductive events (r ≥ 0.50 and p &lt; 0.001). Among the vegetative events, all were classified as non-seasonal (r &lt; 0.5). <em>G. spinosa</em>, showed a significant correlation (p ≤ 0.05) for all meteorological variables evaluated.</p> <p><strong>Conclusion:</strong> The reproductive phenophases of <em>G. spinosa</em> showed strongly seasonal behavior, unlike vegetative events. the period between mid-February and the end of March was the most propitious for fruit collection. No seasonality was observed for the vegetative events. The species proved to be sensitive to El niño conditions. Follow-up phenological studies associated with meteorological variables are important for a better understanding of the dynamics of vegetative behavior in response to climate change.</p> 2022-08-05T00:00:00+00:00 Copyright (c) 2022 MICROSCOPIC IDENTIFICATION OF BRAZILIAN COMMERCIAL WOOD SPECIES VIA MACHINE-LEARNING 2022-01-20T15:35:35+00:00 Jordão Cabral Moulin Dercilio Junior Verly Lopes Lucas Braga Mulin Gabrielly dos Santos Bobadilha Ramon Ferreir Oliveira <p><strong>Background: </strong>Multiple challenges are faced by industry and certification agencies when commercializing tropical species. Anatomical similarities of tropical hardwoods impair identification. Deep learning models can facilitate microscopic identification of wood by using sophisticated techniques such as deep convolutional networks (DCNN). Our objective was to microscopically identify 23 wood species using a custom DCNN model.</p> <p><strong>Results: </strong>Photographs from microscopic slides of each wood species were processed, and the final data set contained 2,448 images. We applied stratified k-fold cross-validation technique during training to increase model’s robustness and trustworthiness. Thus, the dataset was divided into approximately 80% training (1,958 images) and 20% validation (490 images) for each fold. A series of augmentations were performed only on training data to include variations in rotation, zoom, and perspective. Image augmentation was performed on-the-fly. The network consisted of convolutions, max pooling, global average pooling, and fully connected layers. We tested the performance of the DCNN against accuracy, precision, recall, and F1-score on the validation set for each fold.</p> <p><strong>Conclusion:</strong> The machine learned custom model accuracy was considered excellent (&gt;0.90). The model’s worst performance was identified in distinguishing between <em>Toona ciliata</em> and <em>Khaya ivorensis</em>, which was due more to wood variability than to a machine learning deficiency. Future studies should focus on integration, verification/monitoring, and updating of current models for end user manipulation, trust, ethics, and security.</p> 2022-08-05T00:00:00+00:00 Copyright (c) 2022 DECOMPOSITION AND NUTRIENT RELEASE OF EUCALYPTUS HARVEST RESIDUES IN SOUTHEAST BRAZIL 2021-12-09T01:57:29+00:00 Roberto Rorras Moura Marcos Vinicius Winckler Caldeira David Pessanha Siqueira Dione Richer Momolli Deborah Guerra Barroso Robert Gomes Francielle Santana de Oliveira <p><strong>Background</strong>: Eucalypt harvest residues are critical to nutrient balances and forest soil productivity mainly in areas with consecutive forest rotations. However, nutrient release and their relations over decomposition are still poorly understood in tropical sites. We aimed to understand how nutrients are released from leaves, branches, and bark (as harvest residues), and how nutrient concentrations could be limiting the decomposition of each fraction. We measured mass loss and nutrient release of <em>Eucalyptus</em><br /><em>urophylla x Eucalyptus grandis</em> harvest residues for 365 days in Southeast Brazil.</p> <p><strong>Results</strong>: Leaves fraction showed a faster decomposition rate than branches and bark, but nutrient accumulation was observed for all harvest residues, especially bark and branches at later stages of the decomposition. Decomposition of all harvest residues seemed to be P-limited with a stronger limitation occurring for leaf litter decomposers. The decomposition of more lignified residues such as bark and branches was less influenced by climatic variables than leaf decomposition.</p> <p><strong>Conclusion:</strong> Eucalypt harvest residues had a great contribution to soil fertility, and retaining them in the soil systems will enhance soil fertility in the short (leaves) and long-term (branches and bark) and can partially supply the nutrients for the next rotation.</p> 2022-08-05T00:00:00+00:00 Copyright (c) 2022 SPATIAL VARIATION OF EUCALYPTUS FIBRES CONSIDERING THE STRUCTURE OF ANNUAL GROWTH RINGS 2022-03-12T08:30:32+00:00 Fabiola Magalhães Mendes Jonas Massuque Angélica de Cássia Oliveira Carneiro Franciane Andrade de Pádua Paulo Ricardo Gherardi Hein Paulo Fernando Trugilho <p><strong>Background:</strong> The fibres dimensions vary along a tree trunk, and these variations are related to the apical<br />meristem and vascular cambium activities; understanding these variations would guide the best use of<br />wood. There have been studies on the pattern of fibres dimensions’ variation along the tree trunk in the<br />radial and longitudinal directions; however, the vast majority do not take into account the structure of<br />the annual growth rings. Hence, this study aimed to obtain the pattern of fibres dimensions’ variation<br />and their quality indexes along the tree trunk take into account the structure of the annual growth rings.<br />Two<em> Eucalyptus urophylla</em> x <em>Eucalyptus grandis</em> hybrid clones were used in the study. Ten-year-old trees<br />were selected and discs were removed from 13 longitudinal positions. The disks were prepared and the<br />growth rings were subsequently identified and the samples used for maceration were collected. Twenty<br />fibres were measured in the annual growth rings present in each longitudinal position.<br /><strong>Results:</strong> In the longitudinal direction, within the annual growth rings, the fibre dimensions and their<br />quality indices did not show a well-defined pattern of variation. In the radial direction, the length, cell<br />wall thickness, wall fraction, and Runkel ratio of the fibres tended to increase following the pith-bark<br />direction, while the lumen diameter and flexibility coefficient decreased.<br /><strong>Conclusion:</strong> Nevertheless, the fibre width and fibre slenderness index did not present a well-defined<br />pattern of variation in the radial direction.</p> 2022-08-03T00:00:00+00:00 Copyright (c) 2022