Ciências Florestais
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Programa de Pós-Graduação em Ciências Florestais
Centro: CCAE
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URL do programa: http://www.cienciasflorestais.ufes.br/pos-graduacao/PPGCFL
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Navegando Ciências Florestais por Autor "Almeida, Maria Naruna Felix de"
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- ItemAmostragem do Fuste e Efeito da Casca na Qualidade da Madeira de Eucalipto Visando a Produção de Mdf (Medium Density Fiberboard)(Universidade Federal do Espírito Santo, 2024-02-29) Araujo, Stéffany De Lima; Silva, João Gabriel Missia da; https://orcid.org/0000-0002-3714-2745; http://lattes.cnpq.br/2819330926740099; Almeida, Maria Naruna Felix de ; https://orcid.org/0000-0001-6360-7780; http://lattes.cnpq.br/5436388734663217; Vidaurre, Graziela Baptista; https://orcid.org/0000-0001-9285-7105; http://lattes.cnpq.br/2988548512574129; https://orcid.org/0000-0002-9318-2610; http://lattes.cnpq.br/3322377872897794; Sousa, Thaís Brito; https://orcid.org/0000-0001-7776-8649; http://lattes.cnpq.br/8113216921200026; Castor Neto, Thayanne Caroline; https://orcid.org/0000-0002-9740-1665; http://lattes.cnpq.br/6667969524192169; Medeiros Neto, Pedro Nicó de; https://orcid.org/0000-0001-5647-0050; http://lattes.cnpq.br/6441001734932075Knowledge of the characteristics of young eucalyptus used in industries is essential to infer the quality of the products and waste generated. Due to the natural variability of wood, good accuracy of results takes into account the sampling used and, with the large use of eucalyptus in the wood industries, there is also a large generation of waste, especially the bark. Some companies, such as reconstituted wood panel products, use this type of disposal in the manufacturing process. Therefore, the shell should not be treated only as a destruction, but should be evaluated in more detail. That said, the objectives of this dissertation were to evaluate sampling strategies along the tree trunk to determine the basic density of eucalyptus clone wood and evaluate the influence of the presence of bark on the properties of eucalyptus wood through the production of Medium Density Fiberboard. The wood of four eucalyptus clones were studied, two hybrids of Eucalyptus urophylla x Eucalyptus grandis, one Eucalyptus grandis and one Eucalyptus urophylla, aged 6 years, from a commercial plantation in the municipalities of Lençóis Paulista and Agudos, state of São Paulo, Brazil. Five trees were collected per clone, according to the average planning diameter predicted by the forest inventory. Discs were removed along the commercial shaft, in addition to a sample at the position of the diameter at breast height, which were divided into sampling strategies. The properties evaluated were: proportion of heartwood and bark in the discs, basic density, chemical composition, pH and ash for bark, wood with and without bark. The average density between samples ranged from 476.69 to 449.61 kg m-3 . The DBH corresponded to 91.85 to 99.74% of the general bole average, depending on the clone and sampling strategy used. The base-top sampling strategies analyzed did not show significant differences between them, only the one that considers only the DBH was different from the others. Alternative 1 sampling satisfactorily estimated the average density considering all clones as a single material, which is the best strategy for measuring basic density under the conditions given in the present study. The sampling positions from 50% of the commercial height of the bole were better related to the basic density. The proportion of bark varied from 8.22 to 10.25%, while the proportion of heartwood ranged from 26.98 to 36.16%. The basic density of wood was 455 to 502 kg m-3 , for wood with bark it ranged from 447 to 483 kg m-3 , for bark the range was 342 to 368 kg m-3 . The mixture of wood and bark for the evaluated eucalyptus clones was not enough to significantly modify the basic density, chemical composition, pH and ash of the wood. The ash and extractive content were the wood properties most impacted by the presence of bark. Most of the technological properties analyzed in eucalyptus bark were different from wood with and without bark.
- ItemEfeito do clima nas características e propriedades da madeira de um clone de Eucalyptus urophylla(Universidade Federal do Espírito Santo, 2021-01-25) Almeida, Maria Naruna Felix de; Dambroz, Graziela Baptista Vidaurre; https://orcid.org/0000000192857105; http://lattes.cnpq.br/2988548512574129; https://orcid.org/0000000163607780; http://lattes.cnpq.br/5436388734663217; Alvares, Clayton Alcarde; https://orcid.org/0000-0001-7731-6327; http://lattes.cnpq.br/7493167566495413; Pezzopane, José Eduardo Macedo; https://orcid.org/0000000300244016; http://lattes.cnpq.br/3640768649683482; Lousada, José Luis Penetra Cerveira; http://lattes.cnpq.br/5905247610778283; Silva, Maria Emília Calvão Moreira da; http://lattes.cnpq.br/7827204880732022The climate contributes to the growth and development of wood cells, as it interferes with the ecophysiology of the plant, its growth and accumulation of biomass. Considering the extension of Brazilian territory, with marked edaphoclimatic differences, the expansion of forest boundaries and the diversity of results on the influence of climatic variables on the properties of eucalyptus wood, this thesis aimed to evaluate and compare the properties and characteristics of the most eucalyptus clone planted in Brazil (E. urophylla) due to climatic differences between 12 sites along the Brazilian longitudinal gradient. The characteristics of the evaluated wood were: wood density (WD), heartwood percentage (H%) and heartwood and sapwood density (HD and SD), anatomical elements of the xylem (area (VA) and frequency of vessels (VF), fiber wall thickness (FWT) and fiber lumen diameter (FLD) and chemical composition of wood (extractives, lignin, syringyl / guaiacyl ratio (S / G) and ash, CHNS and mineral elements). Absolute values of the variables average air temperature (T), precipitation (P), and soil water deficit (SWD) per site, referring to each year of cultivation and average of six years, were used for comparison. The dendrometric variables mean annual increment (MAI) and increment in cycle volume (ICV) were also used. The means were compared by the Scott-Knott test. Pearson's correlation and linear regression analysis were used to verify the influence of climate on wood characteristics. The most humid sites, located in greater latitudes, presented the highest values of H% (between 61 and 67%). In general, heartwood density was lower than sapwood density, with sites with the lowest MAI values showing the lowest SD values, and wet sites with higher MAI the highest densities. H% showed strong and significant correlations with T, P, SWD, and MAI, while WD showed moderate and significant correlations only with T, MAI and water use efficiency. The influence of climate on the density of E. urophylla wood occurred mainly after the 20 months of tree growth, when WD was mainly correlated with T (r> 0.6). The 1 ° C increase in T resulted in a WD reduction of 0.014 g cm-3 , and increases of 10 m³ ha-1 in the final volume were related to an increase of 0.004 g cm-3 in WD. The density spatialization showed a trend towards a positive density gradient from the north to the south of Brazil. Temperature was again the variable that showed the highest correlations, now with the wood anatomical characteristics. Among sites, climatic differences were more accentuated than between cycles, which led to better correlations between climate and final averages of wood characteristics. Temperature showed strong and negative correlations with WD, VA and FTW (r = -0.89, r = -0.75 and r = -0.83) and positive with VF and FLD (r = 0.62, r = 0, 84). Total lignin, holocellulose and ash do not present significant differences between sites. In the elementary analysis, site 33, which is more humid, differed from the others, with higher content of carbon and hydrogen, and lower values of oxygen. Only the total lignin and S / G ratio showed significant correlations with the meteorological variables, with drier sites presenting a higher S / G ratio. Regarding the quantification of mineral elements, higher levels of one element did not necessarily mean high levels of the others and less productive sites exported less elements per hectare. In general, E. urophylla clone expressed its best phenotype in sites with climatic conditions closest to the conditions for which it was improved, and the choice of the site proved to be a more important factor than the fluctuations in the climate in each location.