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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Determinação da densidade da madeira de clones de Eucalyptus spp. a idades passadas com uso da técnica de atenuação de radiação gama /

Jammal Filho, Fawaz Ali, 1978- January 2011 (has links)
Resumo: O desenvolvimento de florestas clonais de eucalipto tem como metas principais a obtenção de florestas altamente produtivas e de rápido crescimento. Em função, sobretudo da grande diversidade de espécies, o gênero Eucalyptus tem o potencial de atender diversos segmentos da produção industrial madeireira. Um dos principais parâmetros de avaliação da qualidade da madeira é a densidade básica, principalmente quando se visa sua utilização como matéria prima industrial ou energética. Além de ser de determinação relativamente simples, essa propriedade apresenta boa correlação com outras propriedades da madeira. O objetivo deste trabalho foi determinar a densidade básica da madeira relativa às idades de 2, 4 e 6 anos do desenvolvimento fisiológico de Eucalyptus spp. a partir de árvores com seis anos de idade, fazendo uso de perfis densitométricos radiais obtidos pelo método da atenuação de radiação gama e de equações taper e de medições do DAP às idades passadas, para definir as regiões dos perfis correspondentes a cada uma das idades estudadas. Para cada uma das idades estudadas foram amostradas árvores disponibilizadas pela empresa Duraflora S.A., abrangendo dois clones (C1 - maior produtividade e C2 - menor produtividade) e duas regiões distintas (LP - Lençóis Paulista e I - Itapetininga), classificadas e ranqueadas pela empresa como de desempenho superior e inferior, respectivamente. Os perfis densitométricos (densidade aparente e, indiretamente, densidade básica) de discos ao longo da altura das árvores de 6 anos foram obtidos pelo método da atenuação de radiação gama. Posteriormente, a partir de medições diamétricas do fuste das árvores de 2 e 4 foram ajustadas funções taper... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The main objectives of the development of clonal eucalyptus forests are rapid growth and productivity. Considering the great diversity of species, the genus Eucalyptus has the potential to attend different segments of wood industry. One of the principal parameters for wood quality evaluation is the basic density, especially when considering industrial and energy purposes. This property has relatively simple determination and is well correlate to several other wood properties. The objective of this study was to determine basic density of wood on the ages of 2, 4 and 6 years of the physiological development of Eucalyptus spp. 6 years old trees using densitometric radial profiles obtained using the method of gamma ray attenuation and, additionally, taper functions and DAP measurements to define the regions of the profiles corresponding to each one of the past ages (2 and 4 years). Trees provided by Duraflora S.A. were sampled for each of the ages studied covering two clones (C1 - higher productivity and C2 - lower productivity) and two distinct regions (I - Itapetininga and LP - Lençóis Paulista - both at Sao Paulo State, Brazil), ranked by the company as higher performance and lower one, respectively. Densitometric profiles (apparent density - 12% MC - and, indirectly, basic density) from discs along the 6 years old trees height were obtained by the gamma ray attenuation method. Subsequently, based on measurements of stem diameter along the height for 2 and 4 years old trees, taper functions were... (Complete abstract click electronic access below) / Orientador: Adriano Walgner Ballarin / Coorientador: Marcos Antonio de Rezende / Banca: Vlademir Eliodoro Costa / Banca: Elias Taylor Durgante Severo / Mestre
12

Environmental factors affecting wood properties of Eucalyptus spp. grown on the Zululand coastal plain and along the Mpumalanga escarpment of South Africa.

Venter, Frank Leo. January 2003 (has links)
The environmental factors affecting wood property formation of Eucalyptus spp. trees in two distinct geographic areas within South Africa were studied. Wood prop~rty data for trees from 43 sites (26 in Zululand and 17 in Mpumalanga) were collected from work conducted at the Forest and Forest Products Research Centre (FFPRC) at the CSIR (Council for Scientific and Industrial Research) in Durban. The wood properties considered included screened pulp yield, fibre length, wood density and active alkali chemical consumption during pulping. The effect of environmental factors on growth rate (expressed as Site Index at a base age of 5 years) was also measured. A detailed site description for each forest compartment was carried out. Detailed annual and monthly rainfall and minimum and maximum temperature estimates were calculated for each site by interpolating long term means of these variables by splining using the software package Anusplin. These estimates of climatic factors were validated by comparison to the data published in the South African Atlas of Agrohydrology and -Climatology. The outputs of the Anusplin model were used to derive surrogate bioclimatic parameters for each site using the computer program Bioclim. These parameters are considered as better descriptors of the energy-water balance experienced by the plant than normal measures of climate such as mean monthly or annual precipitation. Soil characteristics were measured on samples taken from the individual sites. The effects of these environmental and bioclimatic variables on wood properties were analysed using appropriate statistical techniques. Multiple regression models were used to predict wood properties and it is suggested that this approach could form part of a fibre management system. Wood property prediction models incorporating climate (and bioclimate) alone were preferred to those including soil data as no further site data are required. The effect of edaphic factors was considered to describe any further variation not accounted for by bioclimate alone. Particle size distribution of the soil, as an indication of the water holding capacity of that soil, was not found to effect wood properties or growth significantly. A weak influence of organic matter content in the topsoil on wood density was noted in Mpumalanga. In Zululand, a multiple linear regression using both rainfall of the wettest quarter and mean diurnal temperature range as inputs yielded the best predictive model for growth rate. In this region a combination of precipitation seasonality and mean diurnal temperature range gave the best linear regressi'o,n model describing variation in screened pUlp' yield and fibre length. In Mpumalanga effective rooting depth was found to have a pervasive effect on plant development. Solar radiation (as a measure of energy supply), calculated from a function of latitude, aspect, slope and time of year, was also found to significantly affect the growth rate and SPY of plant material in Mpumalanga. Measures of temperature in both geographic regions were found to significantly affect wood density. / Thesis (M.Sc.)-University of Natal, Durban, 2003.
13

Moisture content in radiata pine wood: Implications for wood quality and water-stress response

Moreno Chan, Julian January 2007 (has links)
This thesis studied the influence of moisture content on the dynamic estimation of stiffness in wood of Pinus radiata D. Don. This is an important non-destructive measure for estimation of stiffness in standing trees, logs and lumber. Moisture content affects both acoustic velocity and density in the fundamental equation of dynamic MOE (DMOE = V²ρ, where V = acoustic velocity and ρ = density). Investigation included measurements with boards in the laboratory considering moisture contents below and above FSP as well as temperatures below and above 0°C. This also included field measurements of trees in contrasting climate sites and over different seasons including a long drought. Methods for measuring green density and moisture content and the patterns of variation of these parameters were also investigated. A secondary component of this thesis explored the wood quality and some mechanisms of tree response to water stress in two contrasting sites in terms or rainfall and water deficits in a region of Australia. The large increases in DMOE for frozen wood above the FSP (4.5 to 6 GPa) will limit the use of DMOE for grading logs in regions with freezing winters. Results from the experiment remeasuring young trees and the upper range of moisture content and temperatures above 0°C from the experiment with boards showed small to moderate variation in DMOE (0.1 to 1 GPa) which calls for further investigation on analytical procedures for adjustment of DMOE. Such procedures should consider that variations in acoustic velocity and density with changes in moisture content are not proportional and that there are counteracting effects between the two parameters. It remains to be investigated whether the typical variation (under normal climate conditions) in sapwood green density observed in our experiments has some implications for the use of DMOE. On the other hand, it is anticipated that the large differences along the stem and among stands in whole-section green density may bias DMOE measurements in logs for resource assessment. This also needs to be investigated. A comparison between acoustic velocity alone and DMOE for resource assessment under different scenarios is recommended. The study in two contrasting climate sites (high-altitude vs. warm-dry) in the Hume region of Forests NSW, Australia, including young (10-11 years) and mature trees (34 36 years) of radiata pine showed distinctive short and long-term responses of trees to cope with the water-limiting environment. In response to long-term water deficits the warm-dry site developed heartwood and thus reduced sapwood earlier and at faster rates than the high-altitude site. The onset of heartwood formation seemed to be triggered by some site threshold for water use as broadly indicated by the sapwood area/ha. The latter was consistently lower for the warm-dry site across the different stands. The warm-dry site also showed increased short-term responses to water stress and these were interpreted as seasonal mechanisms of the trees to cope with the limiting environment. The trees compensated for the lower available moisture and higher transpiration rates by lowering their saturation and disrupting water conduction at some points (cavitation). The inverse trends of cavitation spots and cavitation bands with height in the stem suggested the trees have different strategies to sacrifice conducting xylem depending on the position on the stem. Finally, it is suggested that saturation tended to fall to critical 'safe' levels as a result of water stress and this varied depending on age, site, and position in the stem. Significant decreases in DMOE and basic density were observed for the warm-dry site and were attributed to lower proportions of latewood due to lower rainfall for that site during the period of latewood formation. These showed no obvious association with any of the long-term water-stress traits (sapwood percentage and number of heartwood rings).
14

Classification of timber from Pinus radiata trees exposed to forest fires

Rust, Stephanus Marthinus 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: This study aimed to classify wood from trees that were exposed to forest fires with regards to their end use. Exposure to high temperatures over time is known to degrade wood in various ways. This degradation could limit the end use by altering mechanical, chemical and physical properties, leading to difficulty in processing or failing to meet required specifications for various grades. In this study wood from Pinus radiata trees that were exposed to forest fires of different levels of heat intensity was analysed with regards to its anatomical and physical changes. Trees were visually classified into three classes of burn severity. Moisture content measurements were taken from 135 standing trees, divided among the three classes. 30 trees, 10 from each of the three classes, were sampled and used for CT analysis. Samples were taken to include growth from before and after the fire. Two samples were taken from each tree, one from the charred and one from the uncharred side. The CT data was analysed and used to measure properties like growth ring width, cell wall thickness, lumen diameter and cell wall density. The data was used to compare properties from the charred and uncharred sides within a given year, as well as compare properties between years. The study showed that there were significant differences in the MC between the burnt and unburnt sides of trees from classes 2 and 3. The difference between the MC measurements on the burnt sides of three classes differed significantly from each other. Lightness measurements were taken on samples from classes 2 and 3. These samples showed no significant difference between the burnt and unburnt sides for either of the two classes. The samples from the less exposed class were lighter, but not significantly so. The macroscopic wood density was determined using core samples. A decrease in wood density was observed with an increase in fire exposure. The mean densities for all three classes however still fulfilled the requirements for structural timber set by the SABS. Growth ring width, cell wall thickness and lumen diameter analysis gave varied results, with some cases showing a decline in properties while others were seemingly unaffected. For many of the outcomes of this study, results found by previous studies could not be reproduced. / AFRIKAANSE OPSOMMING: Hierdie studie het gepoog om bome wat aan plantasiebrande blootgestel is volgens hul eindgebruik te klassifiseer. Dit is bekend dat blootstelling aan hoë tempreature hout in vele maniere afbreuk. Hierdie afbreuking kan die eindgebruik van die hout beperk deur die meganiese, fisiese en chemiese eienskappe sodanig te verander dat dit kan lei tot probleme met verwerking of ongeskiktheid vir sterktegrade. In hierdie studie is Pinus radiata bome wat aan plantasiebrande van verskillende grade blootgestel is ondersoek in terme van hul fisiese en anatomiese veranderinge. Bome is visueel in drie klasse van verskillende brandskade gegroepeer. Voglesings is op 135 staande bome, verdeel tussen die drie klasse, geneem. Monsters is van 30 bome, 10 uit elke klas, geneem vir CT analiese. Monsters is so geneem dat dit groei van voor en na die brand ingesluit het. Daar is twee monsters van elke boom geneem, een van die gebrande en een van die ongebrande kant. Die CT data is geanalieseer en gebruik om eienskappe soos jaarringwydte, selwanddikte, lumendiameter en selwand digtheid te meet. Die data is gebruik om eienskappe tussen die gebrande en ongebrande kante, sowel as tussen jare te vergelyk. Die studie het gewys dat daar noemenswaardige verskille is tussen die voginhoud van die gebrande en ongebrande kante van bome uit klasse 2 en 3. Die voginhoud van die gebrande kante van al drie klasse verkil ook noemenswaardig van mekaar. Ligtheidmetings is gedoen op monsters van klasse 2 en 3. Die monsters het nie ‘n noemenswaardige verskil tussen die gebrande en ongebrande kante getoon nie. Alhoewel die klas 2 monsters ligter vertoon het as die klas 3 monsters, was die verskil nie betekenisvol nie. Houtdigtheid is bepaal deur fisiese metings op die monsters wat vir die CT skandering gebruik is te doen. ‘n Daling in digtheid met ‘n toename in blootstelling aan die brand het duidelik na vore gekom. Die digtheid is egter nog hoog genoeg om aan die vereistes vir strukturele hout te voldoen, soos die die SABS bepaal. Jaarringwydte, selwanddikte en lumen diameter het wisselende resultate opgelewer, met sommige gevalle wat ‘n afname in eienskappe wys en ander wat ooglopend onveranderd was. Vir vele van hierdie uitkoms kon die resultate van vorige studies nie bevestig word nie.
15

Efeito do Glyphosate no crescimento, produção e qualidade da madeira do eucalipto (Eucalyptus grandis x E. urophylla) /

Salgado, Tiago Pereira. January 2010 (has links)
Orientador: Pedro Luis da Costa Aguiar Alves / Banca: Edivaldo Domingues Velini / Banca: Pedro Jacob Christoffoleti / Banca: Rinaldo César de Paula / Banca: Roberto Estevão Bragion de Toledo / Resumo: O estudo foi realizado em duas etapas distintas. A primeira, composta por quatro ensaios, constou da aplicação de glyphosate (360 g e.a.L-1) em eucalipto. Em todos os ensaios, mudas foram transplantadas em vasos de 5,0 L. Nos ensaios 1 e 2, foram aplicados volumes de glyphosate no caule do eucalipto. No primeiro ensaio, uma solução de glyphosate na concentração de 3% (v/v) foi aplicada nas doses: 0, 1, 5, 10, 20, 40, 80 e 160 L.planta-1 e, no segundo, a solução a 2% (v/v) foi aplicada nas doses de: 0, 1, 5, 15, 30, 60, 90, 120 e 150 L.planta-1. Nos ensaios 3 e 4, foram feitas aplicações de glyphosate sobre o eucalipto. No ensaio 3 as doses foram: 0, 7,2.10-7, 7,2.10-6, 7,2.10-5, 7,2.10-4, 7,2.10-3, 7,2.10-2, 7,2.10-1, 7,2, 72, 360 e 720 g e.a de glyphosate.ha-1 e, no ensaio 4, as doses foram: 0, 9, 18, 36, 72, 144, 288, 432, 576, 720, 1080, 1440 e 2160 g e.a de glyphosate.ha-1. Nos quatro ensaios foi utilizado o delineamento DIC, com três repetições. Nas plantas foram avaliadas: altura, área foliar, matéria seca de caule e folhas. Os resultados obtidos foram submetidos a análises de regressao. Na segunda etapa, conduzida em campo, o mesmo clone de eucalipto foi plantado em 02/04/2004. Aos 1, 3, 5, 7 e 9 meses após o plantio (MAP), doses 0, 36, 72, 144, 288, 432 g e.a.ha-1 de glyphosate foram aplicadas sobre as plantas. O experimento foi montado em faixas de épocas de aplicação e doses do herbicida. As faixas tinham duas linhas de eucalipto por noventa metros, totalizando 90 plantas. Aos 10, 13, 26, 48 e 62 MAP foram feitas avaliações de altura e diâmetro. Com essas variáveis calculou-se o volume cilíndrico de madeira com casca. Ao final do ensaio (68 meses) foram feitas análises químicas de extrativos, lignina total, holoceluse e densidade basica da madeira nas doses de glyphosate aplicadas aos 5 MAP. Também foi avaliado o rendimento ao cozimento todas as épocas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The study was conducted in two phase. The first, composed of four trials, consisted of the application of glyphosate (360 g a.e.L-1) on eucalyptus. In all the tests, seedlings were transplanted to pots of 5.0 L. In trials 1 and 2, it was applied volumes of glyphosate on the eucalyptus stem. In the first test, a glyphosate solution at 3% (v/v) concentration was applied in the. doses: 0, 1, 5, 10, 20, 40, 80 and 160 4.plant-1 and, in the second, the solution at 2% (v/v) was applied in the doses of: 0, 1, 5, 15, 30, 60, 90, 120 and 150 viL.plant-1. In the trials 3 and 4, it was made applications of glyphosate on eucalyptus. In the trial 3 doses were 0, 7,2.10-7, 7,2.10-6, 7,2.10-5, 7,2.10-a, 7,2.10-3, 7,2.10-2, 7,2.10-1, 7,2, 72, 360 e 720 g a.e of glyphosate.ha-1 and, in trial 4, the doses were: 0, 9, 18, 36, 72, 144, 288, 432, 576, 720, 1080, 1440 and 2160 g e.a of glyphosate.ha-1. In the fourth tests it was used the randomized completely design, with three replicates. Plants were evaluated by height, leaf area, dry matter of stem and leaves. The results obtained were submitted to regression analyzes. In the second stage, conducted in the field, the same eucalyptus clone was planted in 04-02-2004. At 1, 3, 5, 7 and 9 months after planting (MAP), doses 0, 36, 72, 144, 288, 432 g e.a.ha-1 of glyphosate were applied on the plants. The experiment was installed in strip tests of varying herbicide doses. The strips had two lines of eucalyptus by ninety meters, total of 90 plants. At 10, 13, 26, 48 and 62 MAP assessments were held in height and diameter. With these variables it was calculated the wood volume with bark. At the end of the trial (68 months) it was performed chemical analysis of extractives, lignin total holoceluse and basic wood density at doses of glyphosate applied at 5 MAP. It was also evaluated the wood cooking, in all times of application and doses of glyphosate... (Complete abstract click electronic access below) / Doutor
16

Genetic and environmental control of microfibril angle on Eucalyptus wood : its effects on wood traits and implication for selection / Contrôle génétique et environnemental de l'angle des microfibrilles dans le bois d'Eucalyptus : effets sur les propriétés du bois et implication pour la sélection

Gherardi Hein, Paulo Ricardo 16 June 2011 (has links)
Le contrôle génétique et l'environnemental de l'angle des microfibrilles (MFA), les corrélations génétiques du MFA avec d'autres caractères du bois et de croissance, et par conséquent les implications pour la sélection sont très peu documentés pour les Eucalyptus. Les objectifs de cette étude étaient d'établir la variation spatiale du MFA, de la densité du bois (ρ) et de sa rigidité (E); de déterminer les relations entre MFA et propriétés du bois et enfin d'estimer le contrôle génétique et environnemental des caractères du bois et de la croissance dans le cadre de tests clonaux et de test de descendances d'Eucalyptus au Brésil et au Congo. Méthodes classiques, résonance, diffraction des rayons-X et la spectroscopie proche infrarouge ont été combinées pour évaluer les propriétés du bois. La variation du MFA représente 44% de la variation du module spécifique (E/ρ) du bois. La densité du bois est le principal déterminant de la rigidité et de la résistance du bois alors que le MFA joue un rôle secondaire. Les estimations de l'héritabilité sont de modéré à élevées pour le MFA, ρ, E, la lignine de Klason (KL) et les caractères de croissance, selon la position spatiale et le dispositif expérimental. Le contrôle génétique du MFA, ρ et E et leurs corrélations génétiques avec KL et la circonférence à 1.3 mètre des arbres varient avec l'âge. Les résultats suggèrent que les arbres à forte croissance sont génétiquement plus aptes à produire du bois de faible densité et un MFA plus faible pour assurer la rigidité du bois nécessaire à leur développement. La plupart des propriétés du bois sont génétiquement corrélées négativement avec la croissance, bien que corrélations génétiques favorables entre propriétés du bois sont observés. Les corrélations génétiques et environnementales sont parfois de signes opposés selon les caractères considérés. Ceci peut s'expliquer par l'effet pléiotropique des gènes et/ou par le déséquilibre de liaison. Les conséquences de ces résultats sur les stratégies de sélection sont discutées selon l'usage final du bois d'Eucalyptus. / The genetic and environmental control of microfibril angle (MFA), the genetic correlations with other wood and growth traits, and therefore the implications for selection are poorly documented for Eucalyptus. Thus, the objectives of this study were to determine the spatial variation of the MFA, wood density (ρ) and stiffness (E); to determine the relationship between MFA and wood traits and finally to estimate the genetic and environmental control of wood and growth traits from clonal and progeny tests of Eucalyptus in Brazil and Congo. Conventional methods, resonance, X-ray diffraction and spectroscopy were combined to evaluate the wood properties. MFA variation accounted for 44 percent of the variation in specific modulus (E/ρ) of wood. The ρ was the prime determinant on wood stiffness and strength while the MFA played a secondary role. The heritability estimates were moderate to high for the MFA, ρ, E, Klason lignin (KL) and growth traits according to the spatial position and the experimental design. Genetic control of the MFA, ρ and E and their genetic correlations with KL and circumference of 1.3 meters of trees varied with age. The results suggest that tree with potential to grow fast are genetically more likely to produce low ρ and also to decrease the MFA for ensuring stiffness required for their development. Most wood properties were genetically negatively correlated with growth, although favorable genetic correlations between many wood traits were observed. Genetic and environmental correlations were sometimes of opposite signs according to the considered trait. This can be explained by the pleiotropic effect of genes and / or linkage disequilibrium. The implications of these findings for selection strategies are discussed according to the final use of Eucalyptus wood.
17

Efeito do Glyphosate no crescimento, produção e qualidade da madeira do eucalipto (Eucalyptus grandis x E. urophylla)

Salgado, Tiago Pereira [UNESP] 20 September 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:34:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-09-20Bitstream added on 2014-06-13T19:04:55Z : No. of bitstreams: 1 salgado_tp_dr_jabo.pdf: 919699 bytes, checksum: c2b46e671307dd0a1d6135456a265667 (MD5) / O estudo foi realizado em duas etapas distintas. A primeira, composta por quatro ensaios, constou da aplicação de glyphosate (360 g e.a.L-1) em eucalipto. Em todos os ensaios, mudas foram transplantadas em vasos de 5,0 L. Nos ensaios 1 e 2, foram aplicados volumes de glyphosate no caule do eucalipto. No primeiro ensaio, uma solução de glyphosate na concentração de 3% (v/v) foi aplicada nas doses: 0, 1, 5, 10, 20, 40, 80 e 160 L.planta-1 e, no segundo, a solução a 2% (v/v) foi aplicada nas doses de: 0, 1, 5, 15, 30, 60, 90, 120 e 150 L.planta-1. Nos ensaios 3 e 4, foram feitas aplicações de glyphosate sobre o eucalipto. No ensaio 3 as doses foram: 0, 7,2.10-7, 7,2.10-6, 7,2.10-5, 7,2.10-4, 7,2.10-3, 7,2.10-2, 7,2.10-1, 7,2, 72, 360 e 720 g e.a de glyphosate.ha-1 e, no ensaio 4, as doses foram: 0, 9, 18, 36, 72, 144, 288, 432, 576, 720, 1080, 1440 e 2160 g e.a de glyphosate.ha-1. Nos quatro ensaios foi utilizado o delineamento DIC, com três repetições. Nas plantas foram avaliadas: altura, área foliar, matéria seca de caule e folhas. Os resultados obtidos foram submetidos a análises de regressao. Na segunda etapa, conduzida em campo, o mesmo clone de eucalipto foi plantado em 02/04/2004. Aos 1, 3, 5, 7 e 9 meses após o plantio (MAP), doses 0, 36, 72, 144, 288, 432 g e.a.ha-1 de glyphosate foram aplicadas sobre as plantas. O experimento foi montado em faixas de épocas de aplicação e doses do herbicida. As faixas tinham duas linhas de eucalipto por noventa metros, totalizando 90 plantas. Aos 10, 13, 26, 48 e 62 MAP foram feitas avaliações de altura e diâmetro. Com essas variáveis calculou-se o volume cilíndrico de madeira com casca. Ao final do ensaio (68 meses) foram feitas análises químicas de extrativos, lignina total, holoceluse e densidade basica da madeira nas doses de glyphosate aplicadas aos 5 MAP. Também foi avaliado o rendimento ao cozimento todas as épocas... / The study was conducted in two phase. The first, composed of four trials, consisted of the application of glyphosate (360 g a.e.L-1) on eucalyptus. In all the tests, seedlings were transplanted to pots of 5.0 L. In trials 1 and 2, it was applied volumes of glyphosate on the eucalyptus stem. In the first test, a glyphosate solution at 3% (v/v) concentration was applied in the. doses: 0, 1, 5, 10, 20, 40, 80 and 160 4.plant-1 and, in the second, the solution at 2% (v/v) was applied in the doses of: 0, 1, 5, 15, 30, 60, 90, 120 and 150 viL.plant-1. In the trials 3 and 4, it was made applications of glyphosate on eucalyptus. In the trial 3 doses were 0, 7,2.10-7, 7,2.10-6, 7,2.10-5, 7,2.10-a, 7,2.10-3, 7,2.10-2, 7,2.10-1, 7,2, 72, 360 e 720 g a.e of glyphosate.ha-1 and, in trial 4, the doses were: 0, 9, 18, 36, 72, 144, 288, 432, 576, 720, 1080, 1440 and 2160 g e.a of glyphosate.ha-1. In the fourth tests it was used the randomized completely design, with three replicates. Plants were evaluated by height, leaf area, dry matter of stem and leaves. The results obtained were submitted to regression analyzes. In the second stage, conducted in the field, the same eucalyptus clone was planted in 04-02-2004. At 1, 3, 5, 7 and 9 months after planting (MAP), doses 0, 36, 72, 144, 288, 432 g e.a.ha-1 of glyphosate were applied on the plants. The experiment was installed in strip tests of varying herbicide doses. The strips had two lines of eucalyptus by ninety meters, total of 90 plants. At 10, 13, 26, 48 and 62 MAP assessments were held in height and diameter. With these variables it was calculated the wood volume with bark. At the end of the trial (68 months) it was performed chemical analysis of extractives, lignin total holoceluse and basic wood density at doses of glyphosate applied at 5 MAP. It was also evaluated the wood cooking, in all times of application and doses of glyphosate... (Complete abstract click electronic access below)
18

Determinação da densidade da madeira de clones de Eucalyptus spp. a idades passadas com uso da técnica de atenuação de radiação gama

Jammal Filho, Fawaz Ali [UNESP] 26 August 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-26Bitstream added on 2014-06-13T20:40:18Z : No. of bitstreams: 1 jammalfilho_fa_me_botfca.pdf: 720960 bytes, checksum: 2d9beca4c92c311e120befe3687b3035 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O desenvolvimento de florestas clonais de eucalipto tem como metas principais a obtenção de florestas altamente produtivas e de rápido crescimento. Em função, sobretudo da grande diversidade de espécies, o gênero Eucalyptus tem o potencial de atender diversos segmentos da produção industrial madeireira. Um dos principais parâmetros de avaliação da qualidade da madeira é a densidade básica, principalmente quando se visa sua utilização como matéria prima industrial ou energética. Além de ser de determinação relativamente simples, essa propriedade apresenta boa correlação com outras propriedades da madeira. O objetivo deste trabalho foi determinar a densidade básica da madeira relativa às idades de 2, 4 e 6 anos do desenvolvimento fisiológico de Eucalyptus spp. a partir de árvores com seis anos de idade, fazendo uso de perfis densitométricos radiais obtidos pelo método da atenuação de radiação gama e de equações taper e de medições do DAP às idades passadas, para definir as regiões dos perfis correspondentes a cada uma das idades estudadas. Para cada uma das idades estudadas foram amostradas árvores disponibilizadas pela empresa Duraflora S.A., abrangendo dois clones (C1 - maior produtividade e C2 - menor produtividade) e duas regiões distintas (LP - Lençóis Paulista e I – Itapetininga), classificadas e ranqueadas pela empresa como de desempenho superior e inferior, respectivamente. Os perfis densitométricos (densidade aparente e, indiretamente, densidade básica) de discos ao longo da altura das árvores de 6 anos foram obtidos pelo método da atenuação de radiação gama. Posteriormente, a partir de medições diamétricas do fuste das árvores de 2 e 4 foram ajustadas funções taper... / The main objectives of the development of clonal eucalyptus forests are rapid growth and productivity. Considering the great diversity of species, the genus Eucalyptus has the potential to attend different segments of wood industry. One of the principal parameters for wood quality evaluation is the basic density, especially when considering industrial and energy purposes. This property has relatively simple determination and is well correlate to several other wood properties. The objective of this study was to determine basic density of wood on the ages of 2, 4 and 6 years of the physiological development of Eucalyptus spp. 6 years old trees using densitometric radial profiles obtained using the method of gamma ray attenuation and, additionally, taper functions and DAP measurements to define the regions of the profiles corresponding to each one of the past ages (2 and 4 years). Trees provided by Duraflora S.A. were sampled for each of the ages studied covering two clones (C1 - higher productivity and C2 - lower productivity) and two distinct regions (I – Itapetininga and LP – Lençóis Paulista – both at Sao Paulo State, Brazil), ranked by the company as higher performance and lower one, respectively. Densitometric profiles (apparent density – 12% MC – and, indirectly, basic density) from discs along the 6 years old trees height were obtained by the gamma ray attenuation method. Subsequently, based on measurements of stem diameter along the height for 2 and 4 years old trees, taper functions were... (Complete abstract click electronic access below)
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Vėjavartų medienos kokybės vertinimas Dubravos eksperimentinėje mokomojoje miškų urėdijoje / Evaluation of windblown timber quality in Dubrava forest enterprise

Pupelis, Tomas 01 June 2011 (has links)
Magistro darbe tiriama 2010 m. rugpjūčio mėnesį Dubravos EMMU audros pažeisti medynai ir juose pagaminta apvaliosios medienos kokybė. Darbo objektas – 2010 m. rugpjūčio mėnesį škvalo Dubravos EMMU pažeisti medynai. Medienos kokybės bei medžių stiebų sortimentinės struktūros tyrimai atliekami Dubravos EMMU, Vaišvydavos girininkijoje esančiame škvalo pažeistame brandžiame eglyne. Darbo tikslas – Įvertinti vėjavartų apimtį ir medienos kokybės pokyčius Dubravos EMMU. Darbo metodai – Darbe naudoti dokumentų analizės, duomenų grupavimo, palyginimo, vidurkių skaičiavimo ir apibendrinimo metodai. Darbo rezultatai. Išanalizavus Dubravos EMMU audros likvidavimo metu 2010 m. 10-12 mėn. pagamintų pjautinųjų sortimentų kiekius nustatėme, kad pagaminta 76% daugiau negu visada, prastesnės C klasės medienos. Dubravos EMMU, Šilėnų ir Vaišvydavos girininkijose įvertinus vėjo pažeidimus pagal plotą skirtingose augavietėse 60 brandžių medynų, nustatėme, kad intensyviausiai pažeisti medynai, kurie sudaro 35% yra Lcp augavietėse. Įvertinus pažeistus medynus pagal vyraujančią medžių rūšį nustatyta, kad didžiausią pažeistų medynų dalį 46.9% sudaro eglynai. Sortimentuojant 26 vėjo pažeistus medžius nustatyta, kad dėl pakitusios sortimentinės struktūros dėl lūžių taškuose suskeldėjusios medienos, prarandama iš viso 19.8% likvidinės medienos, bei vidutiniškai vieno medžio kirtimo atliekų kiekis padidėja 2.1 karto. Iš vėjo pažeistų medžių, pjautinųjų sortimentų medienos kokybė lyginant su galimai... [toliau žr. visą tekstą] / Study object – 2010.08.08 storm damaged forest stand at Dubrava forest enterprise. Windblown timber quality assessment and storm damaged tree round wood structure assessment was done at Vaišvydava local forest district, at Dubrava forest enterprise. Study aim - to quantify most damaged forest types and to assess the round wood quality losses due to stem breakage and other defects which reduced merchantable timber volume during logging at damaged stands, after 2010.08.08 storm at Dubrava forest enterprise. Methodology – Data grouping, comparison, generalization, document’s analysis. Results - As the main changes in round wood quality during the period of salvage clear cuttings of storm damaged timber at Norway spruce stands at DFE were seen a significant increase of C quality class Norway spruce (Picea abies L) sawn logs – 76 per cent of all sawn logs. Evaluation of windthrow damage on DFE results showed that nearly half (46.9 percent) of all damages occurred on Norway spruce stands. As the most endangered forest soil type of spruce stands, where one third of all damages occurred, was recorded: fertile and humid Myrtillo-oxalidosum site. Survey of 26 storm damaged trees round wood structure showed, that 19.8% reduction of merchantable volume is due to breakage, and due to that fact was seen significant increase - 2.1 time amount of residuals. Windblown tree round wood quality assessment showed significant difference in timber quality if we compare it with normal conditions... [to full text]
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Avaliação do crescimento e da qualidade do lenho de árvores de Eucalyptus urophylla, de 8 anos, de teste de progênies, visando a produção de carvão vegetal / Growth and wood quality evaluation of 8 years Eucalyptus urophylla trees, of progeny tests, in order to produce charcoal

Arizapana Almonacid, Marco Aurelio 08 March 2013 (has links)
As metodologias de análise da qualidade do lenho e dos anéis de crescimento das árvores de eucalipto são importantes para a determinação do incremento anual do seu tronco, da densidade básica e aparente do lenho, dentre outros, visando os programas de melhoramento, como a seleção precoce de árvores geneticamente superiores para a qualidade da madeira, produção de carvão vegetal, etc. Pelo exposto, o presente trabalho avaliou a qualidade do lenho das árvores de Eucalyptus urophylla, de 8 anos,de um teste de progênie, visando a produção de carvão vegetal, instalado em novembro de 2003, no município de Itamarandiba, MG. Foram mensuradas a altura e o DAP de 6 árvores de E. urophylla, das parcelas lineares de 8 árvores, aos 13º, 21º, 38º, 60º e 82º meses, para a determinação do incremento corrente e acumulado do tronco.A qualidade do lenho das árvores em pé foi realizada em novembro de 2008, determinando a resistência do lenho com o equipamento Pilodyn.Em seguida, foram selecionadas, cortadas e desramadas 4 árvores dos blocos 1, 3, e 5, em um total de 312 árvores e cortados cilindros do lenho na base, DAP, 25, 50, 75 e 100% da altura comercial do tronco.Na seção transversal dos discos de lenho foi feita a caracterização macroscópica e a determinação da largura dos anéis de crescimento anuais do lenho. Na aferição da anuidade da formação dos anéis de crescimento foram analisadas as cicatrizes das injúrias da retirada de placa da casca e aplicação da agulha do pilodyn (novembro de 2008, correspondendo ao 5º anel de crescimento) e o diâmetro do tronco mensurado nos inventários florestais. Com base na largura dos anéis de crescimento foram obtidos os incrementos correntes e acumulados do tronco e comparados com os obtidos pela mensuração externa. A densidade básica dos discos de lenho (base, DAP, 25, 50, 75 e 100% da altura comercial do tronco) das árvores foi determinada; a densidade aparente do lenho do DAP de 12 árvores de 26 progênies foi determinada por densitometria de raios X, obtendo o perfil radial de densidade, a densidade aparente média, mínima e máxima dos anéis de crescimento e do lenho. / The methodologies for analyzing the woodqualityand tree-rings of eucalyptus trees are important for determining the trunk annual increment, thebasic and apparent wood density, etc., seeking improvement programs, such as the early selection of genetically superior trees for quality timber, charcoal production, etc. With this aim, the present study evaluated the wood quality of 8 years- Eucalyptus urophyllatrees from a progeny test, installed in November 2003, in the municipality of Itamarandiba, MG, Brazil. The height and DBH of 6E. urophylla trees, in the linear plots of 8 trees were evaluated at 13º, 21º, 38º, 60º and 82º months, for determining the current and accumulated trunk increment. The wood quality of standing trees was conducted in November 2008, determining the wood hardnesswith equipment pylodin. Then, 4 trees were selected, cut and pruned from the blocks 1, 3 and 5, a total of 312 trees, and wood samples from the base, DBH, 25, 50, 75 and 100% of the commercial height were collected. In the wood cross was made the macroscopic characterization and determination of the anual tree-ring width. In assessing the annuity formation of tree-rings were analyzed scars due to the injuries to remotion of the plate of bark and the application of the needle (November 2008, corresponding to the 5th tree-ring), as well as, to thevalues of the trunk diameter measured in forest inventories. Based on the tree-ring thickness were obtained the current and accumulated increases of the trunk diameter and compared with those obtained by the inventory. Thewoodbasic density (base, DBH, 25, 50, 75 and 100% of the trunk height) were determined; also the wood apparent density of the DBH was determined by X-ray densitometry, obtaining the wood radial aparent density profile;the mean, minimum and maximum apparent density of wood and tree-rings.

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