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Swelling, cell wall porosity and chemical modification of woodPapadopoulos, Antonios N. January 2001 (has links)
Kinetic profiles were investigated for the pyridine catalysed reaction of Corsican (CP) and Scots pine (SP) sapwood with a homologous series of linear chain carboxylic anhydrides namely, acetic (AA), propionic (PA), butyric, valeric and hexanoic (HA). With AA. it has been found that the reaction profiles are described by a model where diffusion dominates the reaction process, that is to say that reaction of the reagent molecules with a specific reaction site is rapid compared with diffusion. With longer chain anhydrides, the rate of chemical reaction and diffusion both contributed to the reaction kinetics. The reaction activation energies (Ea) were detennined for the catalysed reaction of pyridine swollen pine sapwood samples and phenolic model compounds (in solution) with the series of anhydrides, using the methods of initial rates and rate constants. Both methods resulted in comparable values. The wood species did not influence the Ea. With wood samples, the Ea was largest for the reaction of AA, and decreased as the molecular weight of the anhydride increased. When the reactions were performed in homogeneous solutions, there was no correlation molecular weight of anhydride and Ea. It is suggested that the lower values obtained for the Ea for reaction with wood are related to the restricted space surrounding the accessible hydroxyl groups (OH). The cell wall micropore network of oven-dried (OD) CP and SP sapwood was investigated by reaction with AA and PA in a non-swelling solvent (xylene) and with swollen wood. Significant differences in reactivity were found between species. The volumetric changes in CP and SP sapwood due to modification with the series of anhydrides were studied. Again significant differences in the response of the wood cell wall were found between species. A comprehensive investigation into the water sorptive properties and into the effect of molecular size of the substituent group upon the sorption of water vapour of softwood modified with the series of anhydrides was perfonned. The sorption isotherms for untreated and chemically modified wood were analysed using the Hailwood-Horrobin model. The results are interpreted by consideration of both the number of OH groups reacted and the volume occupied by adduct in the cell wall. It is considered that the latter effect is more important. In the final part of this study, an approach was made to investigate the cell wall porosity of unmodified and modified wood, using the nitrogen adsorption technique. Results indicated that the true porosity of the cell wall was not determined by this technique.
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An In-Plant Assessment of Heartwood/Sapwood Content in Southern Yellow Pine for Residential Lumber and Industrial Poles and PilingsPenick, Marlon Rayborn 15 August 2014 (has links)
Knowing and understanding the sapwood and heartwood functions and properties are crucial in pressure-treating southern pine. It is very difficult to penetrate heartwood with chemicals. Therefore, knowing heartwood content before treatment will benefit companies in chemical consumption, treating cycles, and, foremost, cost. In this study, two different assessments were conducted in which lumber and pole heartwood/sapwood data was collected from eight treating plants across five Southeastern states. In both assessments, the data indicated some significant differences between similar products from different vendors, but there was no significant difference in heartwood content between plant locations. The results suggested that the amount of heartwood increases as the size and length of the products increase. These findings can argue that the size of raw materials that vendors use and the products they manufacture have more effect on heartwood content than plant location.
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Biology of heartwood formation in Sitka spruce and Scots pineBeauchamp, Kate January 2011 (has links)
Heartwood is the dead, inner layers of wood in the tree which no longer transport water. It is usually dark in colour and has increased decay-resistance compared to the sapwood. Heartwood forms in the transition zone when the ray cells die and deposit chemical extractives in the surrounding xylem. These chemicals convey natural durability which is of value to the forest and timber industry. Despite its value the formation of heartwood is poorly understood. The objective of this PhD is to improve our understanding of heartwood formation in Sitka spruce and Scots pine, the most widely planted species in Britain. Separating heartwood and sapwood at the sawmill can increase timber value due to differences in wood properties. The amount of heartwood varies both with height within, and between trees. Empirical models were developed to describe heartwood and sapwood distribution by diameter, area and ring number 1) within any wood disc 2) with height in the standing tree using taper functions, and 3) its variation between trees. Models will be incorporated into wood quality models to optimise heartwood utilisation. According to pipe theory a certain area of sapwood sustains a volume of canopy, with redundant sapwood converted to heartwood. Sap flux was examined across the sapwood and transition zone in Sitka spruce to understand water transport in relation to heartwood formation and identify seasonal change in transport in the transition zone. Results suggest that the transition zone ceases water transport around dormancy and the amount of heartwood formed may be driven by new wood formation, maintaining sapwood depth. Heartwood formation is a seasonal process, however this has not been confirmed in Sitka spruce or Scots pine, or under UK climatic conditions. Seasonal variation in carbon dioxide and ethylene production by the transition zone were measured to identify the time of heartwood formation, which was late summer through dormancy, consistent with published literature. The role of ethylene in heartwood formation is confirmed. Heartwood formation is an active developmental process, a form of programmed cell death, and as such must be carefully regulated temporally and spatially. Regulation by phytohormones has been proposed but not confirmed. Screening for a broad range of phytohormones during the proposed season of heartwood formation identified an increase in abscisic acid and a decrease in auxin concentration in the transition zone. Abscisic acid, auxin and ethylene also regulate xylogenesis, therefore the same signals that initiate cambial dormancy may also provide the temporal regulation of heartwood formation. The results of this PhD will optimise the use of heartwood in Sitka spruce and Scots pine in the UK and contribute towards selective tree breeding for increased heartwood volume worldwide.
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When Is One Core Per Tree Suffifcient To Characterize Stand Attributes? Results Of A Pinus Ponderosa Case StudyWoodall, C. W. 06 1900 (has links)
Increment cores are invaluable for assessing tree attributes such as inside bark diameter, radial
growth, and sapwood area. However, because trees accrue growth and sapwood unevenly around their pith, tree attributes derived from one increment core may not provide sufficient precision for forest management/research activities. To assess the variability in a tree’s inside bark radius, sapwood radius, and 10-year radial growth estimated by tree cores, two increment cores at 90 degree angles were collected from ponderosa pine (Pinus ponderosa) trees in eastern Montana (n = 2,156). Paired core measurements varied substantially with 13% mean difference for inside bark radius, 19% mean difference for sapwood radius, and 23% mean difference for estimates of radial increment. Furthermore, decreasing crown ratio, decreasing diameter, and increasing site slope were all found to increase differences in estimates derived from paired cores. Whether for management or research purposes, the number of cores that should collected per tree depend on a stand’s susceptibility to reaction wood, required measurement precision, and budgetary constraints.
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Métabolites de Pseudotsuga menziesii : approche métabolomique et rôle dans la résistance / Metabolites of Pseudotsuga menziesii : metabolomic approach and role in resistanceMbakidi-Ngouaby, Henri 28 April 2017 (has links)
Pour l’identification et l’accès aux métabolites secondaires du bois de Douglas, les optimisations des conditions d’extractions ont été réalisées dans différents solvants. L’identification de composés par LC-MS/MS a été privilégiée. L’analyse en LC-ESI-MS/MS des extraits de bois issus des trois zones a été effectuée afin d’identifier les différents groupesde métabolites présents dans chaque zone. Une cinquantaine de métabolites a été identifié. Les groupes de métabolites les plus représentatifs sont les polyphénols et les terpènes qui sont réputés avoir des propriétés antioxydantes, antifongiques à l’origine de la durabilité naturelle du bois. Dans un deuxième temps la quantification relative de métabolites d’intérêt a été réalisée à partir d’échantillon de bois prélevés aux 4 saisons de l’année. Les résultats ont montré que le duramen était la zone la plus riche en métabolites quelque soit la saison. Cependant, la quantité de chaque métabolite varie différemment en fonction des saisons. Pour une majorité de composés quantifiés, le printemps et l’été sont les saisons au cours desquelles le bois accumulait une grande quantité de métabolites. Ces résultats confirment que leduramen est la zone la plus riche en métabolites protecteurs. Ces informations peuvent être utiles pour la sélection des lignées les plus résistantes et l’amélioration de la durabilité naturelle du bois. / For the identification and access to secondary metabolites of Douglas-fir, the optimization of the extraction conditions was carried out in different solvents. The identification of compounds by LC-MS / MS was favored. LC-ESI-MS / MS analysis of thewood extracts from the three zones was carried out to identify the different groups of metabolites present in each zone. About fifty metabolites have been identified. The most representative groups of metabolites are polyphenols and terpenes, which are said to have antioxidant, antifungal properties that are at origin of the natural durability of wood. In a second step, the relative quantification of metabolites of interest was carried out using wood samples taken during the 4 seasons of the year. The results showed that duramen was the richest metabolite area in any season. However, the amount of each metabolite varies differently depending on the season. For a majority of quantified compounds, spring and summer are the seasons in which wood accumulates a large amount of metabolites. These results confirm that the duramen is the area richest in protective metabolites. This information can be useful for selecting the most resistant lines and improving the natural durability of wood.
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Sapwood Amount and its Predictive Equations for Young Hinoki Cypress (Chamaecyparis obtusa) TreesADU-BREDU, Stephen, HAGIHARA, Akio, 萩原, 秋男 12 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
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CARACTERIZAÇÃO DAS PROPRIEDADES FÍSICAS, QUÍMICAS E ANATÔMICAS DA MADEIRA DE Maclura tinctoria (L.) D. DON EX STEUD. / CHARACTERIZATION OF PHYSICAL, CHEMICAL AND ANATOMICAL PROPRIETIES OF Maclura tinctoria (L.) D. DON EX STEUD.Coldebella, Rodrigo 26 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The imminence of Panambi s dam construction, in the municipality of Alecrim, Rio Grande do Sul, affecting the municipality of Porto Mauá, which will overflow thousands of hectares of rainforest, Macluratinctoria s habitat and, the great exploitation of the specie in the region led to the initiation of this research work. The specie is commonly known as Tajuva, presents arboreal sized, and belongs to the botanical family Moraceae, native of Rio Grande do Sul. It is a semideciduous specie, with heights between 10 to 30 meters and, up to 100 cm of diameter; short trunk, with a smooth bark, grayish green with many yellowed lenticels, many times, with the presence of branched thorns. The study aimed to the realization of anatomical description, the chemical characterization and the basic and weighted densities of Maclura tinctoria(L) D. Don Ex Steud wood. The five studied exemplars were obtained through environmental license, in accordance with current legislation. Three wood samples, taken from BHD were used for the manufacture of histological slides and for the fibers quantification. To the determination of wood density and the chemical analysis of wood, disks were removed from the trunk and divided into opposing wedges. It were used opposing wedges removed from six pre-established heights (base, DAP, 25%, 50%, 75% and 100% of commercial height). It was used the ASTM standards to determinate the density, and from TAPPI to the chemical analysis of wood. The wood was anatomically described and illustrated with photomicrographs. The woody tissue consist mainly of fibers (60 ± 3,4%) and rays (20 ± 2,3%), totaling approximately 80%. The remaining, in other words, 20% are divided into vessels (12 ± 4%) and axial parenchyma (8 ± 3%). The mean values, to the basic density (pb) and weighted density (ppond), were 0,539 and 0,555 g/cm³, respectively. The macromolecular constituents of heartwood and sapwood were determinate separately. The average content found for extractives (18,92; 6,32%); Klason lignin (17,58; 17,55%); holocellulose (63,45; 78,59%); alpha-cellulose ( 35,44; 44,38%); hemicelluloses (28,01; 34,21%) and ashes (1,08; 1,35%), to the heartwood and sapwood, respectively, totaling 102,42 ± 3,1%. The Tajuva s wood brings together the anatomical characteristics prevalent in Moraceae, framing the specie in their respective botanical family. It is considered an evolved specie anatomically. The density presents a decrease in the values in relation to the axial position of the plant. The heartwood is constituted of phenolic compounds and acids in a higher proportion relative to the sapwood, which presents higher starch contents. Studies about the natural durability and the wood quality are fundamental to indicate the best application of wood. / A eminência da construção da barragem Panambi, no município de Alecrim, Rio Grande do Sul, afetando o município de Porto Mauá, a qual alagará milhares de hectares de mata atlântica, habitat da Maclura tinctoria e, a grande exploração da espécie na região motivaram o início desse trabalho de pesquisa. Popularmente, a espécie é conhecida como Tajuva, apresenta porte arbóreo, e pertence à família botânica Moraceae, nativa do Rio Grande do Sul. É uma espécie semicaducifólia, com altura entre 10 a 30 metros e, com até 100 cm de diâmetro; fuste curto, com casca lisa, verde acinzentada com numerosas lenticelas amareladas, muitas vezes, com presença de espinhos ramificados. O estudo teve como objetivo a descrição anatômica, a caracterização química e a determinação das densidades básica e ponderada da madeira de Maclura tinctoria (L) D. Don ex Steud. As cinco árvores estudadas foram obtidas através de licenciamento ambiental, de acordo com a legislação vigente. Três amostras do lenho, retiradas do DAP foram utilizadas para a confecção de lâminas histológicas e para a quantificação das fibras. Para a determinação da densidade da madeira e para as análises químicas da madeira, foram retirados discos do tronco e divididos em cunhas. Foram utilizadas cunhas opostas retiradas de seis alturas pré-estabelecidas (base, DAP, 25, 50, 75 e 100% da altura comercial). Utilizou-se as normas da ASTM para determinação da densidade, e da TAPPI para as análises químicas da madeira. O lenho foi anatomicamente descrito e ilustrado com fotomicrografias. O tecido lenhoso é constituído principalmente por fibras (60 ± 3,4%) e raios (20 ± 2,3%), totalizando aproximadamente 80%. O restante, ou seja, 20 % estão divididos entre vasos (12 ± 4%) e parênquima axial (8 ± 3%). Os valores médios, para a densidade básica média (ρb) e ponderada (ρpond), foram de 0,539 e 0,555 g/cm³, respectivamente. Os constituintes macromoleculares da madeira de cerne e alburno foram determinados separadamente. Os teores médios encontrados para extrativos totais (18,92; 6,32%); lignina Klason (17,58; 17,55%); holocelulose (63,45; 78,59%); alfa celulose (35,44; 44,38%); hemiceluloses (28,01; 34,21%) e cinzas (1,08; 1,35%), para cerne e alburno, respectivamente, totalizando 102,42 ± 3,1%. O lenho da Tajuva reúne as características anatômicas predominantes em Moraceae, enquadrando a espécie em sua respectiva família botânica. É considerada uma espécie evoluída anatomicamente. A densidade apresenta decréscimo de valores em relação à posição axial da planta. O cerne é constituído por compostos fenólicos e ácidos em maior proporção em relação ao alburno, que apresenta maiores teores de amido. Estudos sobre a durabilidade natural e a qualidade da madeira são fundamentais para indicar a melhor aplicação da madeira.
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Caracterização anatômica da madeira e potencial dendrocronológico de Schinopsis brasiliensis Eng. (Anacardiaceae) na caatinga sergipanaCardoso, Danielle de Souza 21 July 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Schinopsis brasiliensis Engl. (braúna) is a long-lived species with wide distribution in phytogeographical areas of caatinga and cerrado. Due to uncontrolled exploitation of its timber and the environmental devastation of the caatinga is currently a threatened species. However, these trees have higher dimensions than other species of this environment and, therefore, have higher ecological importance. The biological and ecological characteristics of this species highlights the need of studies about theirs structures and reaction to environmental and climatic changes, among these wood anatomy and dendrochronology. The present study collected specimens of S. brasilienis from São Pedro Farm, in the municipality of Porto da Folha/SE. Living wood and construction wood samples were collected in June and July, 2013, through a non-destructive method, afterwards the samples were kept in the UFS Plant Anatomy and Dendroecology Laboratory, for sample preparations and data analisys. The heartwood and sapwood were significantly different in structure (p<0.05 for all analysis), which revealed that the structure of the heartwood is more resistant to environmental weathering, justifying its use for rural constructions in areas of caatinga. It has growth rings limited by marginal parenchyma band and/or thickness of the fiber walls; small vessels, and tyloses when in the heartwood; rays with procumbent and square cells that store many calcium oxalate crystals; and short and thick fibers. The cross-dating of growth rings series showed correlation of 0.52 between their live individuals and 0.49 among the construction wood. The chronology showed positive correlations with rainfall in the beginning and ending of the rainy season, and fall in the increase rate in the warmer and drier periods of the year, coinciding with the leaf fall and consequent disruption of metabolic activity in new xylem cells´ generation. The analysis of the rings in construction woods allowed new chronology expansion in Brazil, for the previous 20 years to the formation of the first growth ring of the older sample of S. brasiliensis. / A Schinopsis brasiliensis Engl. (braúna) é uma espécie longeva com ampla distribuição nos domínios fitogeográficos da caatinga e cerrado. Por conta da exploração sem controle de sua madeira e da devastação ambiental que assola a caatinga, encontra-se atualmente ameaçada de extinção. Porém, é uma espécie que se destaca por possuir indivíduos com dimensões superiores às geralmente encontradas em outras espécies deste ambiente, e por isso foi classificada como de alta importância ecológica. Suas características biológicas e ecológicas enfatizam a necessidade de estudos sobre suas estruturas e reações às mudanças ambientais e climáticas, dentre estes os de anatomia da madeira e dendrocronologia. O estudo foi realizado com indivíduos de S. brasiliensis provenientes da Fazenda São Pedro, município de Porto da Folha/SE. Amostras de árvores e de madeiras de construção foram coletadas nos meses de junho e julho de 2013, através de método não destrutivo, e posteriormente foram armazenadas no Laboratório de Anatomia Vegetal e Dendroecologia da UFS, para preparo e análise dos dados. A madeira de S. brasiliensis apresentou cerne e alburno significativamente distintos estruturalmente (p<0,05), houve destaque para as características estruturais que tornam o cerne a região mais resistente e duradoura, justificando seu uso em construções rurais em áreas de caatinga. Apresentou anéis de crescimento delimitados por banda de parênquima marginal e/ou espessamento das paredes das fibras; vasos pequenos, com tiloses quando no cerne; raios formados por células procumbentes e quadradas que armazenam muitos cristais de oxalato de cálcio; e fibras curtas e grossas. A espécie foi passível de datação cruzada com 0,52 de correlação entre seus indivíduos vivos e 0,49 entre as árvores e madeiras de construção. Apresentou correlações positivas com a precipitação no início e final do período chuvoso e queda na taxa de incremento nos períodos mais quentes e secos do ano, coincidindo com a queda foliar e consequente interrupção das atividades metabólicas de formação de novas células xilemáticas. A análise dos anéis das madeiras de construção permitiu a inédita expansão de uma cronologia no Brasil, com a inclusão de 20 anos de medidas anteriores à formação do primeiro anel de crescimento da árvore mais velha amostrada na área de estudo.
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Recherche des déterminants biochimiques de la durabilité naturelle du bois de teck (Tectona grandis) / Search for biohemical attributes of natural durability of teak (Tectona grandis)Niamké, Florence Bobolé 22 July 2010 (has links)
La durabilité du bois de teck (Tectona grandis) est une propriété pouvant varier selon le génotype et les facteurs environnementaux. Chez le teck, le degré d'implication des extractibles dans la durabilité naturelle est controversé. A partir d'une approche quantitative incluant les aspects biologiques et technologiques conduites sur des échantillons de bois séchés à l'air ambiant, cette thèse s'est attachée à rechercher les déterminants chimiques de nature phénolique de la durabilité naturelle. Nous avons tout d'abord mis en évidence que les formes osidiques stockées dans l'aubier sont transformées en extractibles de nature quinonique. Nous avons ainsi caractérisé deux composés, l'un dans l'aubier le forsythoside B, un trisaccharide de l'acide caféique et l'autre dans le duramen, le 4',5'-dihydroxy-épiisocatalponol qui ont été identifiés pour la première fois dans le bois de teck. Nous avons mis en évidence que le second composé inhibe la croissance de Trametes versicolor indiquant son rôle directe dans la propriété de durabilité naturelle du bois de teck. Ainsi, les composés du métabolisme des naphthoquinones sont les plus impliqués dans la durabilité naturelle du bois de teck à l'égard de Trametes versicolor et de Poria placenta. Les mécanismes de transformation des sucres pourraient indiquer le niveau de durabilité naturelle des espèces. Ces nouvelles données contribueront aussi à l'amélioration de la qualité du bois qui par ailleurs assure la pérennité des arbres. / Teak (Tectona grandis) wood natural durability is a property which can vary with genotype and environmental factors. The implication of quinonic extractives in the property of natural durability is controversial. Using a quantitative approach including biological and technological conducted on air-dried wood samples, this thesis aimed to search chemical attributes of natural durability. We first demonstrated that osidic forms stored in the sapwood were transformed into quinone derivative. We have characterized two compounds the forsythoside B, a trisaccharide of cafeic acid in the sapwood and in the heartwood, the 4',5'-dihydroxy(epi)isocatalponol that were identified for the first time in teakwood. The latter compound exhibited strong fungicidal activity against Trametes versicolor indicating that its direct implication in decay resistance of teak wood. We have shown that compounds from naphthoquinones metabolism were involved in decay resistance of teak wood against Trametes versicolor and Poria placenta. The mechanisms of sugars transformation may indicate the natural durability level of sustainable species. There these new data will contribute to improve the wood quality that ensures the perennity of trees.
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Efeito do potássio e do sódio no crescimento e nas propriedades do lenho de árvores de Eucalyptus grandis sob duas condições de regime hídrico / Effects of potassium and sodium on growth and wood properties of Eucalyptus grandis trees under two water regime conditionsLegoas, Roger Chambi 09 December 2015 (has links)
No contexto das mudanças climáticas, a sobrevivência e a produtividade das plantações de eucaliptos poderão ser afetadas. Assim, são necessárias pesquisas em nutrição florestal, como a avaliação do K e do Na e sua interação com a disponibilidade hídrica com o crescimento e propriedades do lenho de eucaliptos. Em experimento instalado, em 20 de junho de 2010 de tipo \"Split-plot\", foram avaliadas as árvores de Eucalyptus grandis submetidas a dois regimes hídricos (100% e 63%) e três tipos de fertilização (K, Na e controle). O diâmetro do tronco (cada 15 dias, com dendrômetros) e a altura total (cada 6 meses) das árvores foram mensurados no período do 40º ao 61º mês. A umidade do solo foi analisada semanalmente e a precipitação e temperatura diariamente. Foram analisadas as propriedades do lenho de 48 árvores, no 47º mês, por amostragem destrutiva, avaliando-se a sua densidade aparente, densidade básica, estrutura anatômica e proporção cerne/alburno. Os resultados mostraram que a precipitação influenciou significativamente o crescimento das árvores, seguindo-se a temperatura mínima e a umidade do solo. O K e o Na mostraram interação com a precipitação, (i) no período seco, com a redução do incremento do tronco das árvores com o Na e a sua paralisação com o K, (ii) no período chuvoso, com o aumento do incremento em diâmetro e altura do tronco, em relação ao controle. O Na em relação ao K resultou em menor crescimento das árvores de eucalipto. Com a exclusão de 37% da chuva houve efeito negativo nas árvores com K; no tratamento controle e com aplicação de Na a exclusão não mostrou efeito significativo até o 58º mês. Em relação à (i) densidade do lenho das árvores- ocorreu a sua diminuição com K e Na (menor com Na), e incremento com a menor disponibilidade hídrica; K não diminuiu a densidade sob maior disponibilidade hídrica; (ii) anatomia do lenho- observaram-se vasos de maior diâmetro e menor frequência com K e Na (maior com K); as fibras apresentaram variação significativa com Na (com fibras mais longas e largas com menor espessura da parede); a menor disponibilidade hídrica resultante da exclusão de 37% da chuva não afetou aos vasos e fibras; (iii) relação cerne/alburno- o K e Na promoveram a formação de maior proporção de cerne em relação às árvores do tratamento controle, sem influência significativa da exclusão parcial de chuva. Relações entre anatomia e densidade do lenho mostraram que mudanças nas dimensões das fibras foram acompanhadas de mudanças na densidade do lenho; e maior taxa de crescimento nem sempre se relaciona com a diminuição da densidade do lenho. Os resultados indicaram que a perda de características desejáveis na densidade, fibras e proporção de alburno, com a adição de K ou Na (principalmente Na) na adubação básica, são altamente compensados pela maior produção de lenho, no entanto em regiões mais áridas e com maior risco de seca prolongada, potássio e sódio podem agravar o déficit hídrico. / In the context of climate change, survival and productivity of eucalyptus plantations may be affected. Thus, research is needed on nutrition and forest ecophysiology, such as the evaluation of K and Na and their interaction with water availability on the growth and wood properties of eucalyptus. In a split-plot type, experiment installed on June 20, 2010 we evaluated Eucalyptus grandis trees submitted to two water regimes (100% and 63%) and three fertilizer supplies (K, Na and control). The stem diameter was measured every 15 days with dendrometers and total height, every 6 months in the period from 40th to 61st month. Soil moisture was analyzed weekly and precipitation and temperature daily. The wood properties of 48 trees were analyzed after 47 months, by destructive sampling, evaluating their apparent density, specific gravity, anatomical structure and heartwood/sapwood proportion. The results showed that precipitation significantly influenced the growth of the trees, followed by the minimum temperature and soil moisture. K and Na showed interaction with precipitation, (i) in the dry season, by reducing the growth of the tree trunks with Na and its stoppage with K, (ii) during the rainy season, with increasing growth in diameter and height of the trunk, compared with the control. The Na, as compared to K, resulted in lower growth of the eucalyptus trees. With the artificial exclusion of 37% of throughfall there was a negative effect on the growth of trees fertilized with K; but in the control and Na treatment the rainfall exclusion showed no significant effect until 58º month. In relation to (i) density of the wood of trees, there was a decrease in K and Na (lower with Na), and an increase with lower water availability; although the K did not reduce the density under higher water availability; (ii) wood anatomy- larger vessels with lower frequency were formed with K and Na supply (with higher K); the fibers showed significant variations with Na (longer and wider fibers with smaller wall thickness); and the lower water availability from the of 37% rainfall exclusion did not affect vessels and fibers; (iii) Heartwood/sapwood ratio; K and Na promoted the formation of larger proportion of heartwood in relation to the trees from the control treatment, and there was no significant influence of the partial rainfall exclusion. Relationships between anatomy and wood density showed that changes in fiber dimensions were accompanied by changes in the wood density; and the higher growth rate is not always associated with decreased wood density. The results indicate that the loss of desirable characteristics in density, fiber and proportion of sapwood, with the addition of K or Na (mainly Na) in the basic fertilization are highly compensated by the increased wood production, though in more arid regions with increased risk of prolonged drought, potassium and sodium can aggravate water deficit.
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