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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

Proje??o diam?trica com base em dados observados antes e ap?s o desbaste em povoamentos de eucalipto

Lacerda, Talles Hudson Souza 16 February 2017 (has links)
?rea de concentra??o: Manejo florestal e silvicultura. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-06-09T22:52:32Z No. of bitstreams: 2 talles_hudson_souza_lacerda.pdf: 1852089 bytes, checksum: 5f25d81aee4d02d93913bfc83196ecb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-06-14T19:22:36Z (GMT) No. of bitstreams: 2 talles_hudson_souza_lacerda.pdf: 1852089 bytes, checksum: 5f25d81aee4d02d93913bfc83196ecb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-06-14T19:22:36Z (GMT). No. of bitstreams: 2 talles_hudson_souza_lacerda.pdf: 1852089 bytes, checksum: 5f25d81aee4d02d93913bfc83196ecb3 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O objetivo desse trabalho foi avaliar, do ponto de vista estat?stico e biol?gico, simula??es realizadas por dois modelos de distribui??o diam?trica, ajustados pelos m?todos de aproxima??o linear e m?xima verossimilhan?a, em planta??es de eucalipto submetidos a desbaste. Os dados foram provenientes de um povoamento h?brido de Eucalyptus grandis x Eucalyptus urophylla, sob regime de desbaste, localizado no nordeste da Bahia, vinculados ? empresa BAHIA SPECIALTY CELLULOSE. Os dados utilizados neste estudo foram obtidos nas idades 27, 40, 50, 61, 76, 87, 101, 112, 122, 137, 147, 158 e 165 meses. Esse povoamento foi submetido a tratamentos de remo??o seletiva de 20%, 35% e 50%, nas idades 58 e 142 meses. Utilizou-se dois modelos de distribui??o diam?trica, empregando bases de dados observadas aos 27 meses (antes do primeiro desbaste), aos 61 meses (ap?s o primeiro desbaste) e aos 147 meses (ap?s o segundo desbaste). Por meio dos modelos gerou-se tr?s sistemas, os quais se diferiram no m?todo de ajuste da fun??o Weibull. No sistema 1 os par?metros da fun??o Weibull foram ajustados pelo m?todo de aproxima??o linear. No sistema 2 e no sistema 3, os par?metros foram ajustados pelo m?todo da m?xima verossimilhan?a. As proje??es realizadas pelos sistemas foram confrontadas com as distribui??es diam?tricas observadas, por meio do teste de ader?ncia Kolmogorov-Smirnov a 1% de signific?ncia, e pelo teste F de Graybill, com n?vel de signific?ncia de 5%. Os tr?s sistemas proporcionaram distribui??es diam?tricas projetadas estatisticamente semelhantes ?s observadas, antes e ap?s o desbastes. O sistema 2 apresentou um maior percentual de proje??es n?o significativas para os dois testes estat?sticos empregados. As simula??es realizadas pelos modelos apresentaram realismo estat?stico e tend?ncia do crescimento da distribui??o de di?metros para diferentes porcentagens de desbaste. Houve maior efici?ncia dos modelos ao se utilizar distribui??es diam?tricas observadas em idades imediatamente antes do desbaste. As proje??es das distribui??es diam?tricas, empregando-se como base inicial as distribui??es observadas antes do primeiro desbaste e imediatamente ap?s os desbastes (simula??es 1, 2 e 3), foram mais precisas do que as proje??es obtidas quando foram utilizadas somente as distribui??es diam?tricas observadas antes do primeiro desbaste como base inicial para as proje??es e, em seguida, simulados os desbastes nas idades previstas e, por ?ltimo, realizadas as proje??es empregando-se a distribui??o estimada remanescente do desbaste como base inicial para projetar as distribui??es para idades subsequentes (simula??es 4, 5 e 6). / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / The objective of the study was evaluated from the statistical and biological point of view, simulations performed by two models of diametric distribution, adjusted by linear approximation and maximum likelihood methods, in eucalyptus plantations submitted to thinning. The data were found in a hybrid settlement of Eucalyptus grandis x Eucalyptus urophylla, under thinning regime, located in the northeast region of Bahia, linked to the company BAHIA ESPECIALIDADE CELULOSE. The data used in this study 27, 40, 50, 61, 76, 87, 101, 112, 122, 137, 147, 158 and 165 months. This population was submitted to treatments of selective removal of 20%, 35% and 50%, in the ages 58 and 142 months. Two diametric distribution models were used, using data bases observed at 27 months (before the first thinning), at 61 months (after the first thinning) and at 147 months (after the second thinning). By means of the models three systems were generated, the channels did not differ any method of adjustment of the Weibull function. No system 1 of the Weibull function parameters were adjusted by the linear approximation method. In system 2 and in system 3 the parameters were adjusted by the maximum likelihood method. As the projections performed by the systems were compared with the observed diametric distributions, using the Kolmogorov-Smirnov test at 1% significance, by the Graybill F test, with a significance level of 5%. The three systems provided by the statistically projected diametric distributions for observations, before and after the deviations. System 2 presents a higher percentage of nonsignificant projections for the two statistical tests used. As simulations of model execution demonstrated statistical realism and tendency of growth of the distribution of diameters for different percentages of thinning. There was greater efficiency of the models of use of diametric distributions observed in ages before thinning. As the projections of the diametric distributions, using as an initial basis as distributions observed before the first thinning and after the slabs (simulations 1, 2 and 3), were more accurate than the projections obtained when only diametric distributions observed before the first Thinning as the initial basis for the projections and then simulated the lagging at the predicted ages and finally performed as projections using an estimated remnant distribution of the thinning as the initial basis for designing as distributions for subsequent ages (simulations 4, 5 and 6).

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