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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.
1

Crescimento e propriedades da madeira de Copaifera langsdorffii Desf. sob regime de manejo florestal / Growth and wood properties of Copaifera langsdorffii Desf. under forest management regime

Carmo, Jair Figueiredo do 25 February 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-19T13:33:19Z No. of bitstreams: 1 2016 - Jair Figueiredo do Carmo.pdf: 2232723 bytes, checksum: fe83db2be94c1c93b2be3e9af0a35856 (MD5) / Made available in DSpace on 2017-05-19T13:33:19Z (GMT). No. of bitstreams: 1 2016 - Jair Figueiredo do Carmo.pdf: 2232723 bytes, checksum: fe83db2be94c1c93b2be3e9af0a35856 (MD5) Previous issue date: 2016-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The objective of this research was to study the growth and wood properties of Copaifera langsdorffii trees in an open rain forest, under a forest management system in the state of Mato Grosso, Brazil. Therefore, samples from 20 trees were collected, and the development of the research was divided into two stages. In the first one, a dendrochronological study for the species was carried out and in the second one, a study of the effect of forest management on the anatomical, chemical and physical properties of C. langsdorffii wood. The area where the trees were collected, has as main characteristic the fact that had occurred the first lumbering in 1987 and reaching his second cutting cycle in 2013. During the dendrochronological study, a master chronological series of the tree species and also an analysis of the cambium sensitivity to climatic variations (temperature and precipitation) were done. Furthermore, weather effects of El Ni?o event were found in the growth of those trees. The study of the effect of forest management on the properties of wood, was carried through the anatomical, physics and chemistry characterization of woods that were formed 10 years before and 10 years after the first cutting cycle that had occurred in 1987. It was also analyzed the effect of the distance of the trees studied in relation to the glade (remaining stub) opened in the year of the first lumbering, in 1987. The results indicated that C. langsdorffii has potential to the dendrochronological studies, presenting a significant correlation between the width of the rings within and among those trees. The forest management led to diametrical higher increases than those observed before the first lumbering. It was observed that the higher diametrical growth of trees occurred during periods of the year in which the precipitation rate is higher. The study indicated a significant change in anatomical structure of the wood, by the increased frequency of vessels and decreasing width of rays formed on wood after lumbering in1987. Those results were also observed for the trees distances in relation to the glade. The changes into anatomical structure showed a decrease in the density of the wood formed after 1987. By chemical analysis, 10 chemical elements were found, 4 macro and 6 micronutrients. There was no significant difference in the assimilation of minerals into the wood as a result of forest management. Thus, there was no negative effect on the availability of nutrients to the C langsdorffii. Overall the results showed that forest management was beneficial to the C. langsdorffii, growth because that action led to possible and considerable gains in growth after forest intervention, without incurring significant losses in the anatomical, physical and chemical structure in the wood species. / O objetivo deste trabalho foi estudar o crescimento e propriedades da madeira em ?rvores de Copaifera langsdorffii de uma floresta ombr?fila aberta, sob regime de manejo florestal, no estado de Mato Grosso. Para tanto, foram coletadas amostras de 20 ?rvores, e o desenvolvimento do trabalho foi dividido em duas etapas. Na primeira, foi realizado um estudo dendrocronol?gico para a esp?cie e, na segunda, um estudo do efeito do manejo florestal nas propriedades anat?micas, qu?micas e f?sica da madeira de C. langsdorffii. A ?rea, onde foram coletadas as ?rvores, tem como principal caracter?stica o fato de ter ocorrido a primeira explora??o florestal no ano de 1987 e atingindo seu segundo ciclo de corte no ano de 2013. No estudo dendrocronol?gico, foi constru?da uma s?rie cronol?gica mestre da esp?cie e an?lises da sensibilidade cambial ?s varia??es clim?ticas (temperatura e precipita??o). Al?m disso, verificou-se os efeitos clim?ticos do evento El Ni?o no crescimento das ?rvores. O estudo do efeito do manejo florestal nas propriedades da madeira foi realizado atrav?s da caracteriza??o anat?mica, f?sica e qu?mica dos lenhos formados10 anos antes e 10 anos depois do primeiro ciclo de corte ocorrido em 1987. Foi tamb?m analisado o efeito da dist?ncia das ?rvores estudadas em rela??o ? clareira (toco remanescente) aberta no ano da primeira explora??o de 1987. Os resultados obtidos indicaram que a C. langsdorffii apresenta potencial para estudos dendrocronol?gicos, apresentando uma correla??o significativa da largura dos an?is dentro e entre ?rvores. O manejo florestal propiciou incrementos diametrais superiores aos observados antes da primeira explora??o. Observou-se que os maiores incrementos diametrais das ?rvores ocorreram nos per?odos do ano em que o ?ndice de precipita??o ? maior. O estudo indicou altera??es significativas na estrutura anat?mica da madeira, atrav?s do aumento da frequ?ncia de vasos e redu??o largura dos raios na madeira formada ap?s a explora??o florestal de 1987. Esses resultados tamb?m foram encontrados na an?lise de dist?ncia da ?rvore estudas em rela??o ao toco remanescente. As altera??es na estrutura anat?mica denotaram uma diminui??o da densidade aparente da madeira formada p?s 1987. Atrav?s da an?lise qu?mica foram encontrados 10 elementos qu?micos, sendo 4 macros e 6 micronutrientes. N?o houve diferen?a significativa na assimila??o de minerais na madeira decorrentes do manejo florestal. Assim, n?o houve efeito negativo na disponibilidade de nutrientes para a C. langsdorffii. De modo geral, os resultados encontrados demonstraram que o manejo florestal foi ben?fico para a C. langsdorffii, pois possibilitou ganhos consider?veis de incremento ap?s a interven??o florestal, sem acarretar preju?zos relevantes na estrutura anat?mica, f?sica e qu?mica no lenho da esp?cie.

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