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O presente estudo teve como objetivo avaliar as propriedades físicas, químicas e anatômicas da madeira de Cryptomeria japonica. Foram coletadas árvores, com 13 anos de idade, provenientes de um plantio experimental. A madeira foi classificada como leve ou de baixa densidade (0,314 g cm-3), com valores baixos de contração longitudinal (0,31%), radial (2,09%), tangencial (5,48%) e volumétrica (7,57%), porém elevado coeficiente de anisotropia (2,62), indicando a susceptibilidade dessa espécie frente aos defeitos de secagem. Em relação à composição química, apresentou baixos teores de extrativos (2,14%) e de cinzas (0,32%), porém alto teor de lignina (31,36%). As traqueídes apresentaram comprimento de 2,18 mm; largura de 25,06 µm; diâmetro do lúmen de 15,89 µm e espessura da parede de 4,59 µm, com indicadores interessantes para fabricação de papel, sendo verificada boa qualidade pelo índice de Runkel (0,61) e de enfeltramento (87,78) e média qualidade para coeficiente de flexibilidade (61,23%) e fração da parede (36,94%). As características da madeira de C. japonica indicam potencial para suprir a demanda de matéria-prima do setor industrial, especialmente na região Sul do Brasil.

The bamboo panels particleboards can be advantageous when produced with a mixture of some kinds of wood. However, there are few studies using Bambusa tuldoides for the production of homogeneous particleboards or in combination with wood particles. Therefore, the aim of this study was to evaluate the physical-mechanical quality of particleboard made of different percentages of Bambusa tuldoides and Eucalyptus grandis. To do so, 36 panels were produced composed of a mixture of 0, 25, 50, 75 and 100% of dry matter. The tests realized were moisture, mass density, swelling thickness and water absorption. The mechanical tests were bending, internal bond and screw withdrawal (ASTM 1037, 1999). The results submitted to the correlation test and analyzed by regression. The panels did not get the minimum values of the standards (ANSI A 208.1, 1987) for mechanical tests. It is concluded that the homogeneous bamboo panels obtained superior performance in physical tests than the eucalyptus panels, which are usually used in the industrial sector. However, the insertion of bamboo particles impaired the performance of the panels in the mechanical tests.

O estudo teve por objetivo determinar a composição química, densidade básica e parâmetros morfológicos dos traqueídeos da madeira de Cupressus lusitanica, visando verificar sua adequabilidade para produção de polpa celulósica. Foram utilizadas três árvores, com 16 anos, das quais extraíram-se discos que foram empregados na caracterização química, física e morfológica da madeira. A morfologia dos traqueídeos foi avaliada nos anéis correspondentes as idades 4, 7, 10, 13 e 16 anos. A partir dos parâmetros dos traqueídeos, calcularam-se os indicadores de qualidade da polpa. Foram observados baixos teores de cinzas e extrativos (0,27 e 2,13%, respectivamente), porém alto teor de lignina (32,52%). A densidade básica (0,375 g.cm-3) foi menor que de outras espécies de coníferas utilizadas para produção de celulose. Os traqueídeos apresentaram valores médios de 2,41 mm de comprimento; 31,40 µm de largura; 25,15 µm de diâmetro do lúmen e 3,12 µm de espessura de parede, que tenderam a uma elevação nos valores com o aumento da idade. De maneira geral, a madeira de C. lusitanica apresenta boas características tecnológicas para produção de celulose e papel, especialmente pelos índices morfológicos de qualidade observados.

ABSTRACT The softwood pulp industry is based on the supply of Pinus taeda and P. elliottii woods, and competes for this raw material with other timber sectors. The study aimed to evaluate the wood quality of Pinus patula for pulp and paper production. Trees aged 14 years were obtained from a plantation located in Ponte Alta do Norte, State of Santa Catarina/Brazil. Discs were collected along the commercial height for determining the weighted basic density and its longitudinal variation in the trees, and the chemical composition. For the anatomical characterization, a disc was extracted from the base of each tree to determine the radial variation of tracheids morphological characteristics, and their quality indexes for the production of kraft pulp. The weighted basic density (365 kg.m-3) of the wood was low when compared with other species of the same genus. Regarding the tracheids morphology, a mean length of 2.37 mm; wall thickness of 5.49 µm; width of 40.32 µm and a lumen diameter of 29.09 µm were observed. The chemical composition of the species showed low contents of lignin (25.06%) and ashes (0.27%), compatible content of holocellulose (70.76%), and high content of extractives (6.24%) compared with conifers of traditional use. In general, P. patula species shows characteristics compatible with those traditionally used for the pulp and paper production, and it should be considered in more advanced studies with this species in this segment.

This study investigated the effect of thermal treatment, employed under two treatment conditions on mechanical properties of wood of Pinus taeda L. and Eucalyptus grandis W. Hill ex Maiden. From each species, three 25-year tress were sampled, and from each one, it was taken the first 2-meter long log, which was obtained from two boards of size 7,0 x 20,0 cm (thickness x width respectively) diametrically opposite from where 30 specimens were saw for each treatment. At the first one, called the combined one, the woods were subjected to heat treatment by autoclaving at 130 / ± 3°C and pressure of 2 kgf / cm ² for 3 hours and, after a conditioning period, subjected to heat in an electric oven at 160 / ± 1°C for the same period. The second treatment consisted only of heat treatment in oven. It was also evaluated the pieces of wood without treatment (control). The mechanical properties were evaluated by means of tests for determining the modulus of elasticity and rupture in bending, maximum resistance to compression parallel to the grain and Janka hardness according to ASTM D 143 (1995), and the impact resistance according to ABNT NBR 7190 (1997). For Pinus taeda wood, it was observed that treatment in an oven gave the worst outcomes, both due to the reduction in the values of supported load of a greater number of mechanical properties evaluated, but also as compared to the lowest increments in resistance when it was observed an increase to the same ones with heat treatment. In Eucalyptus grandis, the combined treatment decreased the greatest number of mechanical properties of wood.

This study investigated the effect of two thermal treatment technique on the biological properties of the wood of Pinus taeda L. and Eucalyptus grandis and W. Hill ex Maiden, comparing them with results obtained for the untreated wood. Of each species were sampled three trees at age 25, from where it drew a central plank height DBH for making test specimens were subjected to thermal treatments for later be transformed into pieces of 2.5 x 2.5 x 0.9 cm. In the first treatment the wood were subjected to thermal treatment by autoclaving at 130 ºC/ ± 3 ° C and pressure of 2 kgf /cm² for 3 hours and, after a conditioning period, subjected to heat in an electric oven at 160 °C/ ± 1 °C for the same period. The second treatment consisted of only heat treatment by kiln. Resistance to biological attack was evaluated by accelerated decay test in the laboratory, using a white-rot fungus, Trametes versicolor (Linnaeus ex Fries) Pilat and other brown rot Gloeophyllum trabeum (Persoon. ex Fries) Murr. The combined treatment of the autoclave with electric oven favored the decay of both species of wood fungi employees, except for Pinus taeda submitted to the fungus Trametes versicolor , while treatment in an oven provided increase biological resistance of Pinus taeda wood fungus Trametes versicolor and of Eucalyptus grandis fungus Gloeophyllum trabeum . In general it is concluded that treatment in an oven resulted in more resistant to biological degradation and lower weight loss compared with the combined treatment of the autoclave with electric oven while the latter when applied to both species resulted in an increase in the propensity of biological degradation.

O presente estudo teve por objetivo avaliar a durabilidade natural das madeiras de Apuleia leiocarpa (grápia), Astronium lecointei (muiracatiara) e Enterolobium schomburgkii (fava-orelha-de-negro) ao ataque do fungo causador da podridão branca Trametes versicolor (Linnaeus ex Fries) Pilat, pelo ensaio de apodrecimento acelerado. Foram utilizadas 15 amostras de cerne de cada espécie, nas dimensões 2,5 x 2,5 x 0,9 cm (radial, tangencial e axial, respectivamente). Essas permaneceram durante 16 semanas em incubadora sob ataque do fungo. Após o período de ataque, determinaram-se a perda de massa e a referida classe de durabilidade natural. E. schomburgkii apresentou a maior média de perda de massa (17,5%), seguida de A. lecointei (15,5%), sendo classificadas como resistentes a T. versicolor. A. leiocarpa apresentou maior durabilidade (10,6% de perda de massa), sendo classificada como altamente resistente. A madeira de A. leiocarpa diferiu estatisticamente das demais, indicando potencial de maior durabilidade quando disposta em condições que favoreçam a desenvolvimento deste xilófago.

The present study aimed to evaluate the biological resistance of treated wood from Eucalyptus grandis and Eucalyptus cloeziana under the action of biodeteriorative organisms in laboratory testing. Thus, we used trees of Eucalyptus grandis and Eucalyptus cloeziana, both 16 years old, which was converted into planks and subjected to preservative treatment in an autoclave with chromate copper arsenate (CCA). Then, it was made the specimens for the conduct of accelerated decay test, as recommended by ASTM. From the results, it was observed for the fungus Trametes versicolor that the preservative treatment was effective in reducing the biological degradation of the wood of the two species, with reduced mass loss in 35.17 and 82.31% for wood Eucalyptus grandis and Eucalyptus cloeziana, respectively, as for the fungus Gloeophyllum trabeum mass loss was reduced by 6.79 and 96.65%, compared to the control. Based on the conditions of realization of the present study, it was observed that preservative treatment with CCA is effective in the increasing the biological resistance of the wood under the action of fungi Trametes versicolor and Gloeophyllum trabeum.

This study investigated the physical and mechanical properties of particleboards formed of bamboo (Bambusa tuldoides) and pine (Pinus taeda) and combinations between them. To this end, panels were made, defined by the use of each type of particle (pure or mixed), being set 0, 25, 50, 75 and 100% of proportion to the dry weight, total of 36 panels. The physical tests performed were the moisture content, mass density observed, absorption of water and swelling in thickness and the mechanics were static bending test, screw withdrawal test and internal bond. The results tested for simple correlation and regression analysis. In general, panels pure pine showed better results than just the panels formed by bamboo. The inclusion of bamboo decreases mainly the mechanical properties of panels. All panels were below the minimum standards for the physical and mechanical tests, only internal bond in panels of pine homogeneous had higher values than commercial standards.

O presente estudo teve por objetivo avaliar os efeitos da adição da antraquinona em uma curva de cozimento, com diferentes cargas de reagentes, por meio do processo kraft de polpação, para a madeira de híbrido de Eucalyptus grandis x Eucalyptus urophylla, visando inferir sobre os parâmetros do processo. A madeira foi transformada em cavacos e classificada para condução das curvas de cozimento kraft. As cargas aplicadas foram de 10% a 24% de álcali ativo e 25% de sulfidez, com uma carga de antraquinona de 0,05% (sobre a massa seca de madeira). Avaliou-se o rendimento bruto e depurado, o teor de rejeitos, o número kappa (nível de deslignificação) e o álcali ativo residual. Observou-se que a adição da antraquinona não afetou o rendimento bruto do processo, porém aumentou o rendimento depurado através da redução do teor de rejeitos, em especial para as baixas cargas de álcali ativo (10% e 12%). Outro efeito observado foi a redução do número kappa com a adição da antraquinona, o que indica o aumento da taxa de deslignificação da madeira. Esse aumento é reforçado pelo menor álcali ativo residual, o que se subentende maior aproveitamento dos reagentes no processo.

This study was developed aiming at evaluating the use of constant dynamic elastic obtained by non-destructive testing, as a parameter in the estimation of mechanical properties of Eucalyptus cloeziana obtained by destructive test. With equipment emitting ultrasonicwaves from transducers adapted to dry spots of 45 kHz, we determined the ultrasonic velocity relates to distance and time of transmission of the wave along the length of specimens used in test with nominal dimensions of 2.0 x 2.0 x 30.0 cm in thickness, width and length,respectively. To assess the sensitivity of ultrasound, the samples were tested for evidencedestructively in a universal test for determining the modulus of elasticity and rupture in staticbending. The results showed that the ultrasonic method is a fast and efficient tool for inference of non-destructive wood mechanical properties. However, differences in the adjustment of statistical models showed that the best regression parameters were obtained toestimating the modulus of elasticity, compared with the modulus of rupture.

http://dx.doi.org/10.5902/198050985087This study was carried out to evaluate the potential of use of ‘Canafístula’ wood (Peltophorum dubium (Spreng.) Taub.) in manufacturing particleboards, bonded with tannin and urea-formaldehyde adhesives used in a ratio of 9% of the particles oven-dry weight. For each treatment, three boards were made with a nominal density of 0.63 g/cm3. The properties evaluated were the water absorption for two and 24 hours of immersion and the thickness swelling, the static bending (MOE and MOR), thee screw withdrawal (RAP) and the internal bonding (LI), according to the dimensions and procedures prescribed by ASTM D-1037 (2000). The results were compared with standards established by ANSI A208.1 (1987) and DIN 68761 (1971). The urea-formaldehyde adhesive increased the water absorption of boards and the data results of thickness swelling tests were in accordance with the standards for both treatments. With the exception of the MOR, the resistance data results from the urea bonded boards were below of the minimum standard values; for tannin, all the properties were superior, with the exception of the RAP. According to the results of this study, ‘Canafístula’ wood, when combined with tannin-formaldehyde adhesive, can be an alternative source of raw material for particleboard production.

This study was carried out to evaluate the potential of use of canafístula wood (Peltophorum dubium (Spreng.) Taub.) in manufacturing particleboard, bonded with tannin and urea-formaldehyde adhesives used in a ratio of 9% of the particles oven-dry weight. For each treatment, three boards were made with a nominal density of 0.63 g/cm3. The properties evaluated were the water absorption for two and 24 hours of immersion and the thickness swelling, the static bending (MOE and MOR), the screw withdrawal (RAP) and the internal bonding (LI), according to procedures prescribed by ASTM D-1037 (2000). The results were compared with standards established by ANSI A208.1 (1987) and DIN 68761 (1971). The urea-formaldehyde adhesive increased the water absorption of boards and the data results of thickness swelling tests were in accordance with the standards for both treatments. With the exception of the MOR, the resistance data results from the urea bonded boards were below of the minimum standard values; for tannin, all the properties were superior, with the exception of the RAP. According to the results of this study, canafístula wood, when combined with tannin-formaldehyde adhesive, can be an alternative source of raw material for particleboard production.

This paper evaluated the effect of the combination of two non-industrial methods to treat fence posts of Eucalyptus grandis, on the penetration and retention of water borne preservative. Thus, four fences with 2.20 m in length were treated by replacement of sap and simple diffusion alone and other four ones have combined the two techniques, with water-borne CCB 50% preservative at a concentration of 3.5%. After each treatment condition, the pieces were seasoned in the shade for 30 days. Disks were taken at 0.60 and 1.60 m from the base of the pieces which had one side sanded for analysis of the penetration of the preservative using a solution of chrome azurol S. From the same parts, test specimens were also manufactured in diametrically opposed positions with dimensions of approximately 3.0 x 2.0 x 2.5 cm (radial x tangential x longitudinal) to analyze the retention of the element copper by atomic absorption spectrophotometry method and boron by visible spectrophotometry with azomethine-H, also known as colorimetry. The retention values obtained were compared with the minimum recommended by the Brazilian Association of Technical Standards – ABNT for water borne preservatives which is 6.5 kg of active ingredients per m³ of wood. The penetration achieved by the combined method was considered sufficient for non-industrial treatment, while the retention values were higher than the retention of at least 6.5 kg of active ingredients / m³ of treated wood in all positions and portions evaluated.

This study aimed to evaluate the influence of heat treatments of heating and freezing in the drying defects of Hovenia dulcis Thunb. wood. For this, were used samples from such species of wood concerned with dimensions of 2 x 10 x 20 cm. The heat treatments of heating and freezing were conducted in tank heated to 85ºC and in a freezer at -18ºC, respectively, where the samples remained during 12 and 24 hours for both treatments. After those pre-treatment, the samples were dried an electric oven with forced air circulation at temperatures of 60 and 90°C until the final moisture content achieves set 0 to 2%. The heat treatments showed different effects in function of defects of drying, While heating and freezing treatments reduced the bending towards the samples which did not suffer any of those treatments, the IRT tended to increase it. For the temperatures of drying, the samples submitted to 60ºC showed less pronounced defects, indicating that drying mild drying temperatures decrease the incidence of defects.

This paper evaluated the effect of the combination of two non-industrial methods to treat fence posts of Eucalyptus grandis, on the penetration and retention of water borne preservative. Thus, four fences with 2.20 m in length were treated by replacement of sap and simple diffusion alone and other four ones have combined the two techniques, with water-borne CCB 50% preservative at a concentration of 3.5%. After each treatment condition, the pieces were seasoned in the shade for 30 days. Disks were taken at 0.60 and 1.60 m from the base of the pieces which had one side sanded for analysis of the penetration of the preservative using a solution of chrome azurol S. From the same parts, test specimens were also manufactured in diametrically opposed positions with dimensions of approximately 3.0 x 2.0 x 2.5 cm (radial x tangential x longitudinal) to analyze the retention of the element copper by atomic absorption spectrophotometry method and boron by visible spectrophotometry with azomethine-H, also known as colorimetry. The retention values obtained were compared with the minimum recommended by the Brazilian Association of Technical Standards - ABNT for water borne preservatives which is 6.5 kg of active ingredients per m³ of wood. The penetration achieved by the combined method was considered sufficient for non-industrial treatment, while the retention values were higher than the retention of at least 6.5 kg of active ingredients / m³ of treated wood in all positions and portions evaluated.

The aimed this study was evaluate the use of dynamic elastic constant obtained by non-destructive test as a parameter in the estimative of mechanical properties of Peltophorum dubium (Spreng.) Taub. wood obtained by destructive test. For this, ultrasonic equipment (not-destructive method) was utilized with point-contact transducersof 45 kHz. The ultrasonic velocity was determined considering the wave transmission along the length of the samples, which dimensions of 2.5 x 2.5 x 41 cm in thickness, width and length, respectively. Based on the relationship between ultrasonic velocity and densityof the wood was determined the dynamic elastic constant. The ultrasonic method sensibility was evaluated with subsequent static-bending test where modulus of elasticity and rupture determination. The results showed that ultrasonic method it’s fast and moderately efficient tool for inference non-destructive of mechanical properties. However, was verified difference in the adjustment of statistical models generated to estimate the properties, and found the best regression parameters to estimate the modulus of elasticity,compared with the modulus of rupture.

This study aimed to evaluate the effect of pre-treatments on drying rate of uva-do-japão wood (Hovenia dulcis Thunb.). For this, samples of wood species concerned with dimensions of 2,0 x 10,0 x 20,0 cm (E x L x C), were subjected to pre-treatment of soaking in hot water and freezing. The pre- treatments of heating and freezing were conducted in a thermal tank at 85ºC and a freezer at -18ºC, respectively, where the samples remained for 12 and 24 hours for both treatments. After the pre-treatments, the wood samples were dried in an electric oven at temperatures of 60 and 90°C until the final moisture content. Thedrying rate was significantly influenced by pre-treatments, drying temperature and their duration of them. This rate presented a different behavior according to the duration of treatment: the warning was higher with 12hours whereas the freezing, with 24 hours, was more evident. The increasing duration and temperature observed showed that the tendency of the drying rate is to increase.

The study of physical and mechanical properties of wood is essential for industrial use both in construction and the manufacture of furniture. Thus, the study aimed to determine the physical and mechanical properties of the Araucaria angustifolia wood in terms of three strata phytosociological. For this, 15 trees were felled, five belonging to the upper stratum, the middle stratum five and five for the lower strata. The trees were deployed for the preparation of specimens used for mechanical testing. In the mechanical characterization of the species assays were performed for impact resistance, static bending, compression axial and perpendicular to the fibers. As for the characterization of physical properties, determined the apparent specific gravity at 12% relative humidity for each extract. The results did not show significant differences in the tests of impact resistance and static bending to the strata phytosociological. As for the apparent specific gravity, compression axial and perpendicular there was a change in the values of propertiesbetween the strata phytosociological, is generally butter in the middle and upper strata. Therefore the physical and mechanical properties tend to present higher values these two strata. The data analysis allowed of Araucaria angustifolia wood has moderate mechanical strength when compared with other species studies.

The objective of this study was to determine the mechanical strength of Peltophorum dubium (Spreng.) Taub. wood the fiber saturation point (FSP≈30%) and equilibrium moisture content (TUeq≈12%), trying to correlate and establish models of equations that explain these characteristics. For this, we sampled six trees, where the positionsfrom 0,30 m to 1,30 m concocted in the materials for the testing of mechanical impact resistance and static bending, with dimensions of 2,0 x 2,0 x 30,0 cm. The results obtained in the impact resistance can see that the values of W, K, and the CD timber FSP were higherthan the TUeq in 1,94, 1,82 and 1,36 times, respectively, since the static bending mean values of MOE and MOR of wood to TUeq were larger than the FSP, at about 1,27 and 1,45 times, respectively. The mechanical strength of canafístula wood followed the trend found for other species, in which the impact resistance and static bending, rise and fall with the addition of moisture from the wood, respectively. Both trials showed a significant relationship withdensity for the FSP and the TUeq, indicating that it is possible to predict their behavior based on this variable.

A madeira, devido sua origem orgânica, dependendo das condições ambientais que seja exposta, pode ser deteriorada por agentes biológicos. Em vista disto, é extremamente importante que passe por algum tratamento preservativo, com o intuito de aumentar sua vida útil. A presente pesquisa teve por objetivo avaliar a resistência biológica de madeira tratada de Eucalyptus grandis e Eucalyptus cloeziana sob a ação de organismos biodeterioradores em ensaios de campo. Para tanto, foram utilizadas árvores de E. grandis e E. cloeziana, com 16 anos de idade, que foram desdobradas em tábuas e submetidas à secagem ao ar livre para, posteriormente, efetuar-se o tratamento preservativo em autoclave com arseniato de cobre cromatado (CCA). Em seguida, foram confeccionados corpos de prova para realização do ensaio de campo. Observou-se que o tratamento preservativo foi eficiente na redução da degradação biológica das madeiras das duas espécies. Comparando-se os resultados obtidos para as duas espécies, observou-se que E. cloeziana possui maior aptidão para ser utilizado em condições adversas ou em contato com o solo.

O presente estudo objetivou avaliar o uso da constante elástica dinâmica obtida no ensaio não destrutivo, como parâmetro para estimativa das propriedades mecânicas de rigidez e resistência da madeira de Eucalyptus grandis. Para isto, utilizou-se um emissor de ondas ultrassônicas, o qual teve sua sensibilidade avaliada através da comparação com os valores obtidos no ensaio destrutivo de flexão estática. Os resultados evidenciam que a constante elástica dinâmica pode ser utilizada para inferência não destrutiva da rigidez e resistência da madeira de Eucalyptus grandis, entretanto com ressalvas, pois os ajustes observados foram relativamente baixos, com R²aj. de 0,25 e 0,39, respectivamente. doi: 10.4336/2012.pfb.32.69.109

Aiming to evaluate the development of seedlings of Schinus terebinthifolius under different irrigation depth, an experiment was installed in a greenhouse. The experimental design used was randomized block consisting of 4 treatments with 3 blocks. The irrigation depths evaluated were 8, 10, 12 and 14 mm daily, respectively T1, T2, T3 and T4. Seedling production was performed in tubes with 280 cm ³ filled with pine bark basis substrate and fertilizer. The development of the seedlings, were evaluated by the following characteristics: height of aerial part (APA), diameter at breast height (D),dried mass weight of roots (PMSR), dried mass weight of aerial part (PMSPA), total dried mass (MST) and relation (h/d). The treatment T3 presented the best results in relation to the appraised variables, followed by T2. The Schinus terebenthifolius needs a daily sheet of water of around 10 mm, which is smaller than other pioneer species. doi: 10.4336/2012.pfb.32.69.23O objetivo foi avaliar o desenvolvimento de mudas de Schinus terebinthifolius em diferentes lâminas de irrigação efetiva. O experimento foi instalado na casa de vegetação do viveiro florestal do Departamento de Ciências Florestais da Universidade Federal de Santa Maria. O delineamento utilizado foi o de blocos ao acaso consistindo em quatro tratamentos, com três blocos. Os tratamentos avaliados foram 8, 10, 12 e 14 mm de água diária, respectivamente T1, T2, T3 e T4. A produção das mudas foi realizada em tubetes de 280 cm³, preenchidos com substrato, composto a base de casca de Pinus e fertilizante. A avaliação do crescimento das mudas foi realizada através das seguintes características: altura da parte aérea (APA), diâmetro do colo (D), massa seca de raiz (MSR), massa seca da parte aérea (MSPA), massa seca total (MST) e relação APA/D. O tratamento T3 apresentou o melhor desempenho em relação às características avaliadas, seguido do T2. Assim, pode-se inferir que a produção de mudas de Schinus terebenthifolius necessita de uma lâmina de água diária em torno de 10 mm, a qual é menor do que a necessária para outras espécies pioneiras. doi: 10.4336/2012.pfb.32.69.23

O objetivo foi avaliar o desenvolvimento de mudas de Schinus terebinthifolius em diferentes lâminas de irrigação efetiva. O experimento foi instalado na casa de vegetação do viveiro florestal do Departamento de Ciências Florestais da Universidade Federal de Santa Maria. O delineamento utilizado foi o de blocos ao acaso consistindo em quatro tratamentos, com três blocos. Os tratamentos avaliados foram 8, 10, 12 e 14 mm de água diária, respectivamente T1, T2, T3 e T4. A produção das mudas foi realizada em tubetes de 280 cm³, preenchidos com substrato, composto a base de casca de Pinus e fertilizante. A avaliação do crescimento das mudas foi realizada através das seguintes características: altura da parte aérea (APA), diâmetro do colo (D), massa seca de raiz (MSR), massa seca da parte aérea (MSPA), massa seca total (MST) e relação APA/D. O tratamento T3 apresentou o melhor desempenho em relação às características avaliadas, seguido do T2. Assim, pode-se inferir que a produção de mudas de Schinus terebenthifolius necessita de uma lâmina de água diária em torno de 10 mm, a qual é menor do que a necessária para outras espécies pioneiras. doi: 10.4336/2012.pfb.32.69.23

This study aimed to evaluate the use of dynamic elastic constant obtained in non-destructive testing, as a parameter to estimate the mechanical properties of stiffness and resistance of Eucalyptus grandis. For this we used an emitter of ultrasonic waves, which had its sensitivity evaluated by comparison with the values obtained in the destructive test of static bending. The results show that the dynamic elastic constant can be used as non-destructive inference of the stiffness and resistance of Eucalyptus grandis, though with reservations, because the adjustments observed were relatively low, with R²adj. 0.25 and 0.39, respectively. doi: 10.4336/2012.pfb.32.69.109O presente estudo objetivou avaliar o uso da constante elástica dinâmica obtida no ensaio não destrutivo, como parâmetro para estimativa das propriedades mecânicas de rigidez e resistência da madeira de Eucalyptus grandis. Para isto, utilizou-se um emissor de ondas ultrassônicas, o qual teve sua sensibilidade avaliada através da comparação com os valores obtidos no ensaio destrutivo de flexão estática. Os resultados evidenciam que a constante elástica dinâmica pode ser utilizada para inferência não destrutiva da rigidez e resistência da madeira de Eucalyptus grandis, entretanto com ressalvas, pois os ajustes observados foram relativamente baixos, com R²aj. de 0,25 e 0,39, respectivamente. doi: 10.4336/2012.pfb.32.69.109