Abstract The knowledge of tree attributes of the genus Copaifera sp. (copaiba), such as the height of the trunks, helps to estimate the productive potential of oleoresin and to propose more suitable ways of handling, aiming at optimizing production. This research aimed to test hypsometric equations and deterministic methods of Artificial Neural Networks (ANN) to estimate the total heights levels of the trunks of 31 copaiba trees of the Western Brazilian Amazon, at unknown ages. However, the ANN correlation coefficients obtained were greater than 0,99, demonstrating that they are appropriate for the estimation of height level (h100%). Among the ANN architectures, ANN 3 with 2 neurons in the hidden layer stood out. The application of ANN to estimate the total height of the trunk of Copaifera sp. native trees is a viable tool that can contribute to optimize modeling of the different important aspects to determine the productive potential of oleoresin.

ABSTRACT Climate change is expected to increase the occurrence of severe droughts in the tropics, and little is known about its influence on tree dynamics. Tree-ring width and remote sensing tools can help understand the impacts of climate change on tree growth. We evaluated the applicability of NDVI to obtain phenological metrics (e.g., start, peak, end, and length of growth season) and explored its relationship with tree-ring width of Tectona grandis (teak). The phenological metrics and tree-ring width were correlated with each other, and with both local (temperature, precipitation, solar insolation, Standardized Precipitation Evapotranspiration Index - SPEI) and large-scale (El Niño) climatic variables. The length of season and tree-ring width of teak were positively correlated with precipitation and negatively correlated with temperature in the initial months of the growth period. Tree-ring width was negatively correlated with El Niño events. Climate variables and length of season from the prior period were correlated with the tree-ring width of the current growing period. This study demonstrated that rather than directly affecting productivity, climate might also affect the length of the growing season, which would affect tree growth in the next season.

Abstract Wood quality is related to the characteristics and properties of this material. Understanding the factors that can impact the wood formation is fundamental in the indications for use. The aim of this study was to evaluate the influence of different planting densities on the wood quality and the radial profile on some physical and anatomical characteristics of young trees of Tectona grandis. Nine trees were evaluated in three planting densities: 6 x 2 m; 5 x 2 m; and 4 x 2 m. All trees were subjected to analysis of acoustic tomography, X-ray densitometry, and fiber characterization. Multivariate associations between the variables of interest were evaluated according to the planting spacing and the radial profile by principal component analysis. The results indicated that the wood characteristics of young teak trees are influenced, mainly, by the radial variation (pith-bark).

ABSTRACT Background: Copaiba oil (Copaifera L.) is a raw material used by pharmaceutical, cosmetic, and energy industries. However, the difficulty in locating the oleoresin reservoirs, is an obstacle to its continued supply, affecting the sustainable commercialization of the product. So, the potential of impulse tomography for prospecting oleoresin reservoirs in the trunk of 18 Copaifera sp. trees was tested, in cross-sections at heights levels 0% (DBH), 25%, 50%, 75%, and 100% (1st fork). The impulse tomography prospections (ITP) were performed only at the 0%, in others 12 trees, because of the risk associated with climbing hollow trees. In total 30 trees were tested. Altogether 102 tomograms were analyzed obtaining: average mechanical wave propagation speed (aMPS), minimum mechanical wave propagation speed (minS) and maximum mechanical wave propagation speed (maxS), prospecting height (Hp%) and total tree height (Ht), diameter at the Hp% (Dhp), and low speed mechanical wave propagation percentage areas (LSa%). These variables were analyzed using multivariate analysis. Results: The reservoirs were located exclusively at DBH and confirmed by borer prospection increment in 26.7% of the trees. ITP resulted in 37.3% of correct answers and 62.7% of errors, considering the 99 tomograms. However, it was found that the ITP is efficient to indicate sections for which no significant reservoir or hollow presence is expected to be found. The analysis of the main components showed that, except for Ht, the components are good indicators for the location of the reservoirs. Conclusion: We were able to use tomography to search reservoirs with a significant amount of oleoresin, identify hollow trees, and indicate the exclusion of trees that do not have reservoirs or other alterations.

Abstract Exposing timber to temperatures approaching 200 °C causes thermal modification and changes its characteristics. This study evaluates the effect of various levels of thermal treatment on the physical properties of juvenile and mature wood from rubber tree (Hevea brasiliensis). Boards taken from 53-year-old rubber trees were thermally modified at up to 220 °C. Thermal treatment caused decreases on the oven-dried density, equilibrium moisture content, and swellings on juvenile and mature woods of H. brasiliensis. Influence of thermal modification at 180-200 °C in juvenile wood was lower than in mature wood, whereas the treatment at 220 °C caused a greater variation in properties of juvenile wood. The thermally modified wood is a suitable product for use in environments with high levels of relative humidity.

ABSTRACT There is just little information about the technological aspects of the wood of Brazilian native tree species, which limits their suitable use. The objective of this study was to evaluate the resistograph amplitudes of the wood from six native tree species in different wood density classes, and correlate them with their wood densities to demonstrate the efficiency of this nondestructive technique. The results of the resistograph analysis divided the species into three classes. Analyses of basic and bulk densities of their wood showed statistically significant differences among the evaluated samples that divided them into four classes. The comparison of resistograph method and observed densities showed only a slight difference among the density classes. Therefore, it was found in this study that resistograph analysis may be used for explaining wood properties as well as achieving satisfactory correlations with their actual values, especially the physical properties of species with high wood density.

Resumen Existen pocos estudios relacionados con microdensitometría de rayos X en madera de bosques tropicales nativos. Este estudio tuvo como objetivo determinar la variación radial de la densidad aparente del leño de Amburana cearensis (Allemão) A.C.Sm. por microdensitometría de rayos X. Se seleccionaron 11 árboles, de los que se cortaron secciones radiales de la médula a la corteza, para establecer la densidad aparente y las características anatómicas en tres posiciones radiales. Los resultados mostraron que la madera de A. cearensis presentó valores medios de densidad de madera, mínimo y máximo de 0.55, 0.13 y 0.87 g.cm-3, respectivamente. Asimismo, mostró diferencia significativa en tres posiciones médula (intermedia y corteza), esta diferencia puede ser explicada por la anatomía microscópica, especialmente con los vasos (diámetro, área y el número.mm-2). La microdensitometría de rayos X es una herramienta importante en la evaluación radial de la madera y puede ayudar en la definición de los límites de los anillos de crecimiento de A. cearensis.

Abstract There are few studies related with X-ray micro-densitometry regarding wood from native tropical forests. The objective of this study was to determine the radial variation of the apparent density of the Amburana cearensis (Allemao) A.C.Sm. wood by X-ray micro-densitometry. Indeed, eleven trees were selected, in which radial sections were cut from the pith to the cortex, in order to determine the apparent density and the anatomical characteristic in three radial positions. The results showed that the wood of A. cearensis presented mean values of wood density, minimum and maximum of 0.16 and 0.87 g.cm-3 respectively. Moreover, the wood showed significant difference in three positions of the pith, (intermediate and cortex), and this difference can be explained by the microscopic anatomy, especially with the vessels (diameter, area and number.mm-2). X-ray micro-densitometry is an important tool in the radial evaluation of wood and can help in the definition of the growth rings’ limits of A. cearensis.

ABSTRACT This study aimed to evaluate the effect of log steaming on the physical properties of Eucalyptus grandis Hill ex Maiden wood. Logs with diameters between 20 and 25 cm and length of 2.9 m were studied. Half the logs were maintained in their original condition, and the other half were steamed at 90 °C for 20 hours. Later, the logs were sawn into flat boards, and samples were removed to determine the physical properties of the wood. The results showed that log steaming caused a significant decreases of: (1) 6.38% and 7.98% in the respective basic and oven dried density; and (2) 7.20%, 7.80%, 5.13%, and 8.56% in the volumetric, tangential, radial, and axial linear swelling of wood.

RESUMO O presente trabalho teve como objetivo caracterizar a formação de anéis de crescimento no lenho de Khaya ivorensis, bem como, analisar a variação da morfologia dos elementos de vaso, visando ao entendimento do crescimento dessa espécie em plantios experimentais. Para tanto, discos da base de cinco árvores foram coletados e, após o polimento da seção transversal, realizou-se a demarcação dos limites dos anéis de crescimento. Um estudo anatômico da madeira foi realizado com objetivo de caracterizar os anéis e por meio de imagens digitalizadas dos discos foi mensurada a largura dos mesmos. Foi obtida uma série histórica de dados referente ao diâmetro das árvores para estabelecer uma correlação com a largura dos anéis mensurada ao longo dos anos. Os limites dos anéis de crescimento da madeira de mogno africano são demarcados por uma fina camada de parênquima marginal, tendo sido constatada a presença de falsos anéis. Foi observada entre as árvores correlação de crescimento anual significativa de 0,62, sendo o incremento radial do lenho irregular nos primeiros anos (anéis largos e estreitos), com destaque para o 3º e o 11º ano de crescimento, em que foram observados os maiores incrementos, devido a uma tendência biológica de adaptação ao ambiente e pela ocorrência de um desbaste realizado na área de plantio, respectivamente.

ABSTRACT The objective of this study was to characterize the formation of growth rings in Khaya ivorensis wood, as well as to analyze the variation in the morphology of the vessel elements, aiming to understand the growth of this species in experimental plantations. Disks from the bases of five trees were collected, and after polishing the cross-section, demarcation of the growth rings limits was carried out. The anatomical study of the wood was conducted with the purpose of characterizing the rings, and their width was measured by means of scanned images of the disks. A historical series of data was obtained concerning the diameter of the trees to establish a correlation with the width of the rings measured over the years. The growth rings limits of African mahogany wood are demarcated by a thin layer of marginal parenchyma, and the presence of false rings has been observed. Significant annual growth correlation of 0.62 was observed among the trees, being the radial increment of irregular wood in the first years (wide and narrow rings), and highlighting the 3rd and 11th year of growth in which the largest increases were observed due to a biological adaptation tendency to the environment and the occurrence of thinning carried out in the planting area, respectively.

RESUMO As árvores de Pinus taeda – introduzidas no Brasil em 1880 e em ensaios experimentais em 1936 – têm sido relacionadas na literatura especializada ao processo de invasão biológica de algumas áreas de campos gerais e de altitude dos estados do Paraná e Santa Catarina, de cerrado no estado de São Paulo, de restinga no estado de Santa Catarina e de pampas no estado do Rio Grande do Sul. Os anéis de crescimento anuais formados no lenho das árvores de Pinus taeda constituem importante ferramenta na avaliação do processo de invasão biológica. Com esse objetivo, no presente trabalho avaliou-se a dispersão espacial-temporal de sementes analisando-se os anéis de crescimento do lenho de árvores de Pinus taeda de plantações e de regeneração natural na região de Faxinal do Céu, estado do Paraná. Os resultados possibilitaram determinar a idade e a taxa de crescimento do tronco das árvores de Pinus taeda de plantações, a data da germinação, a área de dispersão das sementes e a taxa de crescimento das árvores de regeneração natural. Os resultados permitem, da mesma forma, discutir o processo de invasão de árvores de Pinus taeda pela dispersão das sementes em áreas limítrofes às plantações florestais.

ABSTRACT The Pinus taeda trees - introduced in Brazil in 1880 and in experimental trials in 1936 - have been listed in specialized literature of biological invasion process in some areas of general fields and altitude of the states of Parana and Santa Catarina such as, the savanna in the state São Paulo, sandbar in the state of Santa Catarina and pampas in the state of Rio Grande do Sul. The annual tree-rings formed in the wood of Pinus taeda trees constitute an important tool in the evaluation of the biological invasion process. The present study aimed to evaluate the spatial-temporal dispersion of seeds by analyzing the tree-rings of Pinus taeda trees from plantations and natural regeneration in the region of Faxinal do Céu, state of Paraná. The results allowed determining the age and growth rate of the pine trees trunk from plantations; the date of germination, the seed dispersal area and the growth rate of trees of natural regeneration. The results allow, likewise discussing the invasion process of pine trees by seed dispersal in areas close to forest plantations.

RESUMO O lenho de tração é uma estrutura anatômica importante, que permite a reorientação do tronco e participa na arquitetura dos ramos, tendo a função de reforço estrutural. Contudo, sua presença em grande quantidade afeta significativamente as propriedades tecnológicas da madeira, como no caso da seringueira. Entretanto, ainda há demanda de informações acerca de sua origem, distribuição e características estruturais nessa espécie. Portanto, esse trabalho objetivou caracterizar as estruturas celulares no lenho de tração e lenho oposto em Hevea brasiliensis (seringueira) e sua distribuição radial e longitudinal. Para tanto, discos da base e do meio do fuste comercial foram coletados de três árvores provenientes de um plantio comercial localizado em Tabapoã - SP. Foram mensurados o diâmetro tangencial dos elementos de vaso, comprimento de fibras (gelatinosas e não-gelatinosas), ângulo microfibrilar e proporcionalidade de elementos celulares, e a relação entre a presença de fibras gelatinosas e o diâmetro de vasos. Foram observadas fibras gelatinosas nos dois tipos de lenho e nas duas alturas do fuste avaliadas. Os dois tipos de lenho foram diferenciados pelo comprimento de fibras gelatinosas e a proporção de parênquima axial. A região de tração no meio do fuste foi a que mais se diferenciou das demais, com fibras gelatinosas mais compridas e menos abundante, maiores diâmetro e proporção de vasos.Além disso, foi observado menor diâmetro de vasos nas regiões com alta proporção de fibras gelatinosas, sugerindo que a planta investe mais em sustentação que na condução de líquidos.

ABSTRACT Tension wood is an important anatomical structure for its participation in the orientation of the trunk and the architecture of the branches as a function of structural reinforcement. However, its presence in large amounts significantly affects the technological properties of wood, just as in the rubber tree. Nevertheless, there is still demand for information about the origin, distribution and structural features in this species. Thus, this study aims to characterize the cellular structures in tension and opposite wood in Hevea brasiliensis (rubber tree), as well as its radial and longitudinal distribution. Discs at the base and the middle of the commercial logs were collected from three trees in a commercial plantation located in Tabapoã - SP. Tangential diameter of vessels, fiber length (gelatinous and non-gelatinous fibers), microfibril angle and proportionality of cellular elements (vessels, axial parenchyma, ray, gelatinous fibers and non-gelatinous fibers) were measured, and influence of gelatinous fiber presence in vessel diameter was observed. Gelatinous fibers were observed in the two types of wood and in the two trunk heights. Both types of wood were distinguished by gelatinous fiber length and the proportion of axial parenchyma. The tension wood in mid-trunk was the most different, with long gelatinous fibers and less abundant, larger vessel diameter and vessel proportion. Moreover, smaller vessel diameter was observed in the regions with a high proportion of gelatinous fibers, suggesting that the plant invests more support than in liquid transport.

ABSTRACT The increment zones width in the xylem of Swietenia macrophylla King was investigated by dendrochronological methods in an undisturbed and a strongly disturbed tropical site near Aripuanã, Mato Grosso, Brazil (10°09’ S, 59°26’W). The study aimed to assess the impact of forest disturbance on the relationship between precipitation and the cambial growth of this species. Tree-ring width chronologies were developed for both sites from cross-dated increment curves. Simple correlations were computed between monthly precipitation records and the annual increment of Swietenia for the period between 1870 and 2000. Logging activities and altered land use caused a significant decrease of the water supply of the Swietenia trees grown in the disturbed area compared to trees grown in the undisturbed area. Consequently, the precipitation of almost the total growing season had a significant influence on the tree ring width of Swietenia grown in the disturbed area, while in the undisturbed forest area the significant correlation between monthly precipitation and the tree ring width of Swietenia was restricted to the beginning of the growing season (November to January). However, the reconstruction of monthly precipitation data from the tree ring width records was more precise using the chronology developed from tree ring width records of undisturbed trees compared to the chronology developed from tree ring widths from the disturbed area. It was concluded that the use of the tree ring widths of Swietenia as climate proxies is restricted to certain months of the year and requires tree ring width chronologies developed from trees grown in undisturbed or only slightly disturbed forest areas without severe anthropogenic changes in microclimate.

RESUMOO objetivo deste trabalho foi estudar a influência da idade da árvore na distribuição de assimilados e na formação de extrativos do cerne de Robinia pseudoacacia. A translocação de assimilados em plantas de 6 e 15 anos de idade foi mensurada em maio e em agosto de 2006, por meio do método do carbono 14. Os teores de extrativos na madeira da zona de transição entre o cerne e o alburno e em anéis de crescimento do cerne foram analisados por HPLC. Em maio e em agosto, em todas as plantas, os brotos e as folhas jovens tiveram a atividade específica do 14C mais forte, quando comparados com outras partes da planta (atividade específica de 14C em brotos/folhas de plantas de 6 anos de idade: 35,2-37,0%; plantas de 15 anos de idade: 31,4-32,2%). No entanto, em plantas analisadas em agosto de 2006, na zona de transição entre o cerne e o alburno, houve também um forte sequestro de assimilados, enquanto que, nas plantas analisadas em maio de 2006, apenas pequenas quantidades de assimilados foram translocadas. A quantidade de assimilados transportados para a zona de transição entre o cerne e o alburno, foi significativamente maior em plantas de 15 anos de idade, em comparação com as de 6 anos de idade. Isso foi acompanhado por um teor mais elevado de extrativos no cerne formado pelas plantas mais velhas em relação ao cerne da madeira formada pelas plantas jovens. Os resultados indicam que a distribuição desigual de assimilados em plantas de Robinia mais jovens e mais velhas afeta a formação de extrativos de cerne, o que pode levar a uma menor durabilidade natural do cerne formado por árvores mais jovens em relação ao cerne formado por árvores mais velhas.

ABSTRACTThis study aimed to investigate the influence of tree age on the assimilates partitioning and its significance for the formation of heartwood extractives in Robinia pseudoacacia L. (black locust). Assimilate translocation in 6- and 15-year-old plants was measured in May and August 2006 using the 14CO2 feeding method. The heartwood extractives content in the sapwood-heartwood transition zone and in individual tree rings of the pure heartwood were analysed by HPLC-chromatography. All plants, buds and young leaves showed the strongest 14C specific activity compared to other plant parts in May and August(14C specific activity in buds/leaves of 6-years old plants: 35.2-37.0%, 15-years old plants: 31.4-32.2%). However, in plants labelled in August 2006 at the sapwood-heartwood transition zone also showed a strong assimilates sink, while only small amounts of assimilates were translocated to the sapwood-heartwood transition zone in the plants labelled in May 2006. The amount of assimilates transported to the sapwood-heartwood transition zone was significantly higher in the 15-year-old plants compared to the 6-year-old plants. This was monitored by a higher content of extractives in the heartwood formed by the older plants compared to heartwood formed by the younger plants. The results indicate that uneven assimilate partitioning in younger and older black locust plants affects the heartwood extractives formation, which might lead to a lower natural durability of the heartwood formed by younger trees compared to heartwood formed by older trees.

O Schizolobium parahyba (Vell.) Blake, popularmente conhecido por “guapuruvu”, apresenta anéis de crescimento distintos, evidenciados por maior espessamento de suas paredes no lenho tardio e pela presença de parênquima em faixa marginal. Neste contexto, o objetivo deste estudo foi construir a cronologia dos anéis de crescimento de árvores de S. parahyba de ocorrência na ReBio de Tinguá, RJ, visando gerar conhecimento sobre a dinâmica de crescimento da espécie, bem como sobre a sensibilidade da formação dos anéis de crescimento por fatores climáticos. Das 30 árvores selecionadas foram coletadas quatro amostras radiais do tronco, utilizando-se uma sonda Pressler. As amostras passaram por polimento mecânico para melhor visualização dos anéis de crescimento e posterior delimitação e mensuração da largura deles. Para verificar a sincronização da largura dos anéis de crescimento e gerar uma série mestra da cronologia para a espécie, foi utilizado o programa estatístico COFECHA. A espécie apresenta ótimo potencial dendrocronológico, confirmado por elevada correlação da largura dos anéis de crescimento dentre e entre árvores. Além disso, exibe elevado coeficiente de sensibilidade média, que demonstra resposta às variações ambientais. O crescimento da espécie é correlacionado com a precipitação na estação seca.

The Schizolobium parahyba, popularly known as “guapuruvu”, has distinct growth rings evidenced by increased thickening of the walls in the late wood and the presence of marginal parenchyma bands. In this context, the aim of this study was to construct a chronology of the growth rings of S. parahybatrees, occurring in Biological Reserve Tinguá, RJ, in order to generate knowledge about the growth dynamic of the species, as well as the sensitivity of the formation of growth rings by climatic factors. From the 30 selected trees, four radial trunk samples were collected using a Pressler borer. The samples suffered mechanical polishing for better visualization of the growth rings and subsequent delineation and measurement of the width of these rings. The statistical program COFECHA was used to check the synchronization of the width of growth rings and generate a series of master chronology of the specie. The species has a great dendrochronological potential, which was confirmed by a high correlation of the width of growth rings within and between trees. Moreover, the species has a high average sensitivity coefficient, which shows a response to environmental variations. The growth of the species is correlated with precipitation in the dry season.

O objetivo deste estudo foi estudar a qualidade da superfície usinada da madeira de Eucalyptus grandis, submetida ao processo de tratamento térmico. As operações de usinagens realizadas nas tábuas obtidas a partir do processamento de mecânico de seis árvores foram: desempeno, desengrosso, rasgo na furadeira horizontal, furação, furação para dobradiça e lixamento. Foram selecionadas 208 tábuas de 125 x 25 x 500 mm, sendo 104 não tratadas e 104 tratadas termicamente a uma temperatura final de 190ºC. A avaliação da superfície foi feita de acordo com a norma ASTM D-1666/87. O resultado mostrou que a madeira de Eucalyptus grandis apresenta um bom comportamento durante os testes de usinagem, obtendo notas 1 e 2 (excelente e bom), exceto para os testes de furação para a dobradiça no furo passante e furação com broca de 12, 8 e 6 mm, pois alcançaram notas entre 2 e 4 (bom, regular e ruim). O tratamento térmico diminuiu a quantidade de defeitos nas amostras usinadas, com exceção para o defeito grã arrancada, em algumas operações de usinagem.

The objective of this study was to study the machined surface quality of Eucalyptus grandis wood submitted to heat treatment. The machining operations realized on the boards obtained from the processing of six trees were: planing, thicknessing, tear in horizontal drilling, drilling, drilling hinge and sanding. 208 boards of 125 x 25 x 500 mm were selected, with 104 untreated and 104 heat-treated boards at maximum temperature of 190ºC. The evaluation of the surface was performed according to ASTM D-1666/87 standard. The result showed that the Eucalyptus grandis wood presents a good behavior during the machining tests, obtaining notes 1 and 2 (excellent and good), except for drilling hinge test in the bolt hole and drilling with 12, 8, 6 mm, reaching notes between 2 and 4 (good, regular and bad). The heat treatment reduced the number of defects on the machined samples, except for torn grain in some machining operations.