Seleção de espécies e procedências de Pinus sp para a região de Assis, Estado de São Paulo

Pós-graduação em Agronomia - FEIS

Variação genética e desempenho de progênies de Pinus caribaea var. hondurensis para produção de madeira e resina

Pós-graduação em Agronomia - FEIS

Effects of belt speed, pressure and grit size on the sanding of pinus elliottii wood

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ensaios não-destrutivos de propagação de ondas em toras e madeira serrada de Pinus. taeda L.

In this paper it was evaluated the influence of the relative position of logs on the trees, the type of wood (juvenile and mature wood and pith) and the dimension of sawed wood elements on the velocity of propagation of stress waves into the material on condition. P. taeda L wood (43 years old trees) from Horto Florestal of Manduri (latitude 230 00’ south, longitude 400 19’ west and altitude de 700 m) São Paulo State, Brazil were used, considering its easy growth rings visualization and the better ju regions definition. Six trees were randomly chosen in the plantation. Trees were sawed into 4 logs (2,5 m long each. In each log it was delimited the central board (80mm tick) region and the lateral boards (25mm tick) regions, cons right hand. It were evaluated relation between velocity of stress waves on logs and the correspondent lumber (central and lateral boards), on green condition, on the three main region of the elements (mature wood results obtained revealed the concordance between velocities of stress waves in the material before and after the its mechanical processing. It was also revealed statistical differences between the velocity of stress waves at juvenile wood, mature wood and pith regions. Keywords: stress wave method, velocity 17 destrutivos de propagação da propagação de ondas de tensão em toras e madeira serrada de taeda L. Hernando Alfonso Lara Palma - Universidade Estadual Paulista Faculdade de Ciências Agronômicas – FCA/UNESP – Botucatu - SP, e-mail: awballarin@fca.unesp.br Luiz Antonio Vasques Hellmeister - Universidade Estadual Paulista - Faculdade de Arquitetura, FAAC/UNESP – Bauru - SP, e-mail: hellmeister@faac.unesp.br Este trabalho teve como objetivo analisar a influência do tipo de lenho, da posição da tora ao longo do fuste e das dimensões das peças desdobradas, na velocidade de as de tensão (Stress wave method), na condição de madeira verde. P. taeda L., originária de árvores de plantio do Horto Florestal de SP., com idade aproximada de 43 anos, pela facilidade de identificação dos anéis imento e demarcação das regiões de madeira adulta e madeira juvenil. Foram amostradas 6 árvores distintas, escolhidas ao acaso do talhão selecionado. De cada árvore foram retiradas 4 toras com comprimento de 2,5 m cada. Foram demarcadas nas toras a ha central (8 cm de espessura) e 4 tábuas laterais (espessura comercial de 2,5 cm), sendo duas à esquerda e duas à direita da prancha central. Foram avaliadas as relações existentes entre as velocidades de propagação das ondas de tensão na madeira íntegra (toras) e desdobrada (pranchas e tábuas), na condição de madeira verde, nas três regiões distintas do lenho: medula, madeira adulta e madeira juvenil. A análise comparativa dos resultados revelou a concordância entre as velocidades antes e após o desdobr madeira. Houve diferenciação estatisticamente significativa entre as velocidades de propagação das ondas de tensão nos lenhos adulto, juvenil e na medula. -destrutivos, método das ondas de tensão, Pinus taeda stress wave tests on green logs and lumber of Pinus taeda In this paper it was evaluated the influence of the relative position of logs on the trees, the type of wood (juvenile and mature wood and pith) and the dimension of sawed wood elements on the velocity of propagation of stress waves into the material on L wood (43 years old trees) from Horto Florestal of Manduri (latitude 19’ west and altitude de 700 m) São Paulo State, Brazil were used, considering its easy growth rings visualization and the better juvenile and mature wood regions definition. Six trees were randomly chosen in the plantation. Trees were sawed into 4 logs (2,5 m long each. In each log it was delimited the central board (80mm tick) region and the lateral boards (25mm tick) regions, considering 2 boards on the left and 2 at the right hand. It were evaluated relation between velocity of stress waves on logs and the correspondent lumber (central and lateral boards), on green condition, on the three main region of the elements (mature wood, juvenile wood and pith). Comparative analyses of results obtained revealed the concordance between velocities of stress waves in the material before and after the its mechanical processing. It was also revealed statistical differences ty of stress waves at juvenile wood, mature wood and pith regions

Influence of storage period of pieces in stiffness of pinus elliottii Glulam Beams

This study aimed to investigate the influence of storage time (0, 48 hours) of Pinus elliottii pieces and the tests to obtaining modulus of elasticity (static bending and transversal vibration) in glued laminated timber beams, produced with resorcinol based adhesive and 0.8 MPa compaction pressure. After pieces were properly prepared, part of them was used in immediate three manufacturing glulam beams, tested after adhesive cure, and part stored for 48 hours under a roof with a temperature of 25°C and relative humidity of 60% for subsequent manufacturing and testing three other glulam beams. Results of analysis of variance (ANOVA) revealed that the storage period was significant influence in modulus of elasticity obtained in static bending test (8% reduction from 0 to 48 hours). This not occurred with modulus of elasticity obtained by transversal vibration test (no significant influence). ANOVA results showed equivalence of means in both test procedures. New researches ire needed to better understand the investigated phenomenon, using new wood species, other storage conditions and a great number of samples.

Avaliação da influência de variáveis na produção de batentes de painel EGP de Pinus taeda

Pós-graduação em Engenharia Mecânica - FEG

Avaliação da qualidade da madeira de cinco espécies de Pinus destinadas à produção de celulose

Pós-graduação em Ciência Florestal - FCA

Avaliação de desempenho no processo de lixamento de madeiras das espécies Pinus elliottii e Corymbia citriodora

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Alkaline sulfite/anthraquinone pretreatment followed by disk refining of Pinus radiata and Pinus caribaea wood chips for biochemical ethanol production

BACKGROUND: Alkaline sulfite/anthraquinone (ASA) cooking of Pinus radiata and Pinus caribaea wood chips followed by disk refining was used as a pretreatment for the production of low lignified and high fibrillated pulps. The pulps produced with different delignification degrees and refined at different energy inputs (250, 750 and 1600 Wh) were saccharified with cellulases and fermented to ethanol with Saccharomyces cerevisiae using separated hydrolysis and fermentation (SHF) or semi-simultaneous saccharification and fermentation (SSSF) processes. RESULTS: Delignification of ASA pulps was between 25% and 50%, with low glucans losses. Pulp yield was from 70 to 78% for pulps of P. radiata and 60% for the pulp of P. caribaea. Pulps obtained after refining were evaluated in assays of enzymatic hydrolysis. Glucans-to-glucose conversion varied from 20 to 70%, depending on the degree of delignification and fibrillation of the pulps. The best ASA pulp of P. radiata was used in SHF and SSSF experiments of ethanol production. Such experiments produced maximum ethanol concentration of 20 g L-1, which represented roughly90% of glucose conversion and an estimated amount of 260 L ethanol ton(-1) wood. P. caribaea pulp also presented good performance in the enzymatic hydrolysis and fermentation but, due to the low amount of cellulose present, only 140 L ethanol would be obtained from each ton of wood. CONCLUSION: ASA cooking followed by disk refining was shown to be an efficient pretreatment process, which generated a low lignified and high-fibrillated substrate that allowed the production of ethanol from the softwoods with high conversion yields. (C) 2012 Society of Chemical Industry

Effects of exogenous calcium or oxalic acid on Pinus taeda treatment with the white-rot fungus Ceriporiopsis subvermispora

Pinus taeda wood chips were treated with the biopulping fungus Ceriporiopsis subvermispora in calcium-or oxalic acid-amended cultures. The secretion of hydrolytic and oxidative enzymes was inhibited only in the cultures having the highest concentration of calcium (1400 mg kg(-1) wood). Calcium decreased the availability of free oxalic acid, inhibited fungal growth, and reduced lignin mineralization and transformations. Oxalic acid amendment in the cultures was found not to affect the lignin mineralization and transformations; however, it did inhibit the depolymerization reactions detectable in the residual lignin that was retained in the biotreated wood. C. subvermispora presented catabolic activity for oxalic acid in the cultures amended with 1660 mg acid kg(-1) wood, whereas oxalic acid was synthesized when it was amended at low amounts or initially absent in the cultures. These data suggest one ideal ratio of oxalic acid in C. subvermispora cultures and indicate that its exogenous addition does not necessarily accompany the further degradation of lignin. Crown Copyright (C) 2012 Published by Elsevier Ltd. All rights reserved.

Ascensão capilar de água em substratos de coco e de pinus

O uso da irrigação por capilaridade na produção de mudas em viveiros pode trazer vantagens ao uso de água e sua utilização adequada requer o conhecimento da capacidade de ascensão de água no meio de crescimento das raízes, atributo pouco estudado. Para avaliar esta condição fundamental, este trabalho tem como objetivo avaliar a ascensão de água em substratos comerciais de coco e pinus, em dois padrões de tamanho de partículas e em duas condições de umidade, para indicar aquele que possua as melhores características físicas para aplicação na irrigação por capilaridade. Utilizou-se o método de ascensão capilar, com colunas desmontáveis de anéis preenchidas com substratos, avaliando-se os seguintes tempos de contato do fundo da coluna com a lâmina de água: 0,25, 0,5, 1, 2, 4, 8, 16 e 24 horas, com 10 repetições por tempo testado. Pelos resultados, observou-se que a maior ascensão capilar acumulada em 24 horas de ensaio foi obtida para os substratos de textura fina de coco e de pinus. Além disso, a hidrofobia do substrato de coco seco recomenda que as irrigações nesse material devem ter frequências maiores que substratos de pinus, evitando seu secamento. O substrato de pinus, por não apresentar esse comportamento, deve ter turnos de rega mais espaçados, principalmente sob textura fina. Devido à sua maior retenção de água e capacidade de elevação de água quando umedecido, o substrato fino de coco é mais adequado à irrigação por capilaridade em recipientes como tubetes.

Dinâmica do potencial matricial em substratos de pinus e coco sob ação da capilaridade

O tamanho médio de partículas e a porosidade dos substratos condicionam as propriedades matriciais, interferindo na capacidade de retenção e de transmissão da água no meio. O conhecimento desses atributos é fundamental em processos de irrigação por capilaridade, para que o molhamento atinja as camadas superiores dos recipientes com níveis de tensão de água facilmente disponível. O presente trabalho teve como objetivo estudar a ascensão de água por capilaridade para determinar a posição mais apropriada do nível de saturação na ascensão capilar em recipientes com substratos de coco e pinus, de textura grossa e fina. Foram efetuados experimentos avaliando a ascensão de água por capilaridade em colunas segmentadas preenchidas com os substratos. Os valores de umidade em cada segmento foram calculados gravimetricamente e relacionados aos de tensão estimados pela curva de tensão dos substratos. Os substratos com textura fina apresentaram melhor elevação de água por capilaridade, com melhor elevação da umidade em níveis de tensão de água disponível. O substrato de coco fino apresentou água disponível em todo o perfil do recipiente, enquanto o de pinus apresentou as camadas superiores do recipiente com água retida em tensões abaixo do ponto de murcha permanente. O substrato fino de coco apresentou os melhores resultados para aplicação na irrigação por capilaridade, permitindo recomendar o seu uso com o nível de saturação posicionado a cinco centímetros do fundo do recipiente por quinze minutos.

Will Whole-Tree Harvest of Jack Pine (Pinus banksiana) deplete soil nutrients in low-productivity sand soils?

In 2009 and 2010 a study was conducted on the Hiawatha National Forest (HNF) to determine if whole-tree harvest (WTH) of jack pine would deplete the soil nutrients in the very coarse-textured Rubicon soil. WTH is restricted on Rubicon sand in order to preserve the soil fertility, but the increasing construction of biomass-fueled power plants is expected to increase the demand for forest biomass. The specific objectives of this study were to estimate biomass and nutrient content of above- and below-ground tree components in mature jack pine (Pinus banksiana) stands growing on a coarse-textured, low-productivity soil, determine pools of total C and N and exchangeable soil cations in Rubicon sand, and to compare the possible impacts of conventional stem-only harvest (CH) and WTH on soil nutrient pools and the implications for productivity of subsequent rotations. Four even-aged jack pine stands on Rubicon soil were studied. Allometric equations were used to estimate above-ground biomass and nutrients, and soil samples from each stand were taken for physical and chemical analysis. Results indicate that WTH will result in cation deficits in all stands, with exceptionally large Ca deficits occurring in two stands. Where a deficit does not occur, the cation surplus is small and, chemical weathering and atmospheric deposition is not anticipated to replace the removed cations. CH will result in a surplus of cations, and will likely not result in productivity declines during the first rotation. However even under CH, the surplus is small, and chemical weathering and atmospheric deposition will not supply enough cations for the second rotation.