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Search Results: 1 - 10 of 179548 matches for " Agostinho Lopes de; "
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Estratifica??o vertical em floresta ombrófila densa de terra firme n?o explorada, Amaz?nia Oriental
Souza, Deoclides Ricardo de;Souza, Agostinho Lopes de;
Revista árvore , 2004, DOI: 10.1590/S0100-67622004000500008
Abstract: this study was carried out at the forest management unit (fmu) in tracajás farm (02o35'53" s and 47o47'10"w), owned by nova era agroflorestal, in paragominas, pará, brazil. the objective was to accomplish the vertical stratification of an unexplored terra firme dense ombrophylous forest using cluster and discriminant analysis. the forest was stratified in homogeneous areas, denominated classes of volumetric stock i, ii and iii. in each class, five 100 x 100 m plots were randomly set up, where the total heights of the individual trees (dbh > 15.0 cm) were used for vertical forest stratification. the trees were organized in increasing order of total height and classified in 1 m amplitude classes, from the minimum to the maximum total height. a total height xmatrix was elaborated, with each variable xij representing the total height of the i-th tree classified into j-th class of total height. this x-matrix was the input for the cluster and discriminant analysis. the application of cluster analysis resulted into hierarchical and sequential clusters of height classes into total height strata (inferior, medium, and superior). discriminant analysis demonstrated a 100% correct classification. the vertical structure subdivision of forest into total height strata, by multivariate statistics proved the method efficient for uneven-aged forest vertical stratification.
Emprego do método BDq de sele??o após a explora??o florestal em Floresta Ombrófila Densa de Terra Firme, Amaz?nia oriental
Souza, Deoclides Ricardo de;Souza, Agostinho Lopes de;
Revista árvore , 2005, DOI: 10.1590/S0100-67622005000400014
Abstract: the objectives of this study were to analyze the diameter structure of a terra firme dense rain forest after selective logging, to apply the bdq method in the silvicultural treatment activities and to manage the forest aiming at a balanced diameter structure. the research was carried out at the forest management unit (fmu) in tracajás farm (02o35'53" s and 47o47'10"w), owned by nova era agroflorestal, in paragominas, pará, brazil. the forest was stratified into homogeneous areas, called classes of volume stock i, ii, and iii. in each of the stock classes, five plots of 100 x 100 m (1 ha) were randomly set up for measurement of the individuals with dbh > 15cm. in the center of each 100 x 100 m plot, a subplot of 10 x 100 m (0,1 ha) was established for measurement of the individuals with 5cm < dbh < 15 cm. the bdq selection method was used taking into account the remaining basal area (b), maximum diameter (d) and the de liocourt constant (q). in the stock class i, the proposed management method allowed the removal of 56.4 trees/ha, 3.33 m2/ha and 67.64 m3/ha, with a 13.1% reduction of the basal area. in the stock class ii, 53.7 trees/ha, 3.88 m2/ha and 65.96 m3/ha were removed, with a 16.2 % reduction of the basal area. in the stock class iii, 63.3 trees/ha, 3.13 m2/ha and 46.76 m3/ha were removed, with a 14.0% reduction of the basal area. few trees or a deficit was observed in the higher diameter classes due to the selective logging. the periodical removal of trees should occur in the lower diameter classes, aiming at a balanced diameter distribution and the conduction of the forest to a balanced structure during the cutting cycle, leading to a continuous use of the forest woody products.
Análise multivariada para estratifica??o volumétrica de uma floresta ombrófila densa de terra firme, Amaz?nia Oriental
Souza, Agostinho Lopes de;Souza, Deoclides Ricardo de;
Revista árvore , 2006, DOI: 10.1590/S0100-67622006000100007
Abstract: the objective of this study was to propose a method for stratification of an unexplored terra firme dense ombrophylous forest into classes of volumetric stocks, by using the techniques of cluster and discriminant analysis. the research was carried out at the forest management unit (fmu) in tracajás farm (02o 35'53" s and 47o 47'10"w), owned by nova era agroflorestal, in paragominas, pará, brazil. an census (100%) was accomplished in which the volumes of commercial whole-tree with dbh > 45 cm were estimated for 55 commercial species in 49 stands 10 ha each. the estimated volumes of individual commercial whole-trees were organized in a increasing order. a x-matrix was built, in which each variable xij represented the i-th volume classified in the j-th stand. this x-matrix was the input for the cluster and discriminant analysis. the application of the cluster analysis resulted in hierarchical clusters of the stands in stock classes. the analysis of the dendrogram allowed the stratification of the forest in three homogeneous and distinct groups, denominated classes of volumetric stock i, ii and iii. the discriminant analysis pointed out that 100% of the stands were correctly classified. the multivariate classification of the forest into homogeneous classes of volumetric stocks showed to be an efficient method for stratification of uneven-aged forests, which can be constituted by extracts, compartments, site classes and annual production units.
Análise multivariada para estratifica o volumétrica de uma floresta ombrófila densa de terra firme, Amaz nia Oriental
Souza Agostinho Lopes de,Souza Deoclides Ricardo de
Revista árvore , 2006,
Abstract: O objetivo deste estudo foi propor um método de estratifica o em classes homogêneas de estoque volumétrico da floresta ombrófila densa de terra firme n o explorada, empregando-se as técnicas de análises de agrupamento e discriminante. A pesquisa foi conduzida na Unidade de Manejo Florestal (UMF) da Fazenda Tracajás (02o35'53"S e 47o47'10"W), pertencente à empresa Nova Era Agroflorestal, de propriedade do Grupo Rosa Madeireira, Município de Paragominas, Estado do Pará. Foi realizado um censo (100%), no qual se estimaram os volumes do fuste comercial das árvores com dap > 45 cm de 55 espécies comerciais em 49 talh es de explora o com 10 ha cada um. Reuniram-se os volumes estimados do fuste comercial das árvores individuais por talh o em ordem crescente. Elaborou-se uma matriz X de dados desses volumes, em que cada variável x ij representou o i-ésimo volume classificado no j-ésimo talh o. A matriz X foi utilizada como input nas análises de agrupamento e discriminante. A aplica o da análise de agrupamento, método de Ward, resultou em agrupamentos hierárquicos dos talh es em classes de estoques. A análise do dendrograma permitiu estratificar o povoamento em três grupos homogêneos e distintos, denominados classes I, II e III de estoques volumétricos. A análise discriminante, método de Fisher, indicou que 100% dos talh es foram corretamente classificados. A classifica o multivariada da floresta em classes de estoques volumétricos mostrou-se um método eficiente na estratifica o de áreas homogêneas de florestas ineqüianeas, as quais podem se constituir em estratos, compartimentos, classes de sítio e unidades de produ o anual.
Altera??o florística de áreas de florestas exploradas convencionalmente em planos de manejo, nos domínios de floresta atlantica, Minas Gerais-Brasil
Coelho, Danilo José da Silva;Souza, Agostinho Lopes de;
Revista árvore , 2007, DOI: 10.1590/S0100-67622007000200007
Abstract: the objective of the present study was to analyze the changes in the composition of species, in forest management areas having as control the legal reserve area, and it was carried out in fragments of semideciduous seasonal forests in the zona da mata region of minas gerais state. following the harvest of each fmp, the comparison between forest management areas and legal reserve areas showed that, in relation to changes in diversity of the fmp tree species, the verifiers ecological group, use group and rare species group indicated that the forest management areas of all the fmps were statistically equal (p>0.05) to the legal reserve areas. the verifier species richness indicated that the forest management areas and the legal reserve areas of the fmp28 and fmp29 were statistically equal (p>0.05), whereas the fmp30 and fmp16 were statistically different (p<0.05). the verifier species diversity indicated that the forest management areas were statistically different (p>0.05) from the legal reserve areas in fmp29, fmp30 and fmp16 and statistically equal (p<0.05) in the fmp28. the greatest similarity of species occurred between the groups formed by the fmp29amf and fmp29arl, and the smallest similarity occurred between the groups formed by fmp29arl, fmp29amf, fmp28arl, and fmp16arl, fmp16amf, fmp30arl, fmp30amf, fmp28amf.
Análise da atividade florestal no município de Vi?osa-MG
Fontes, Alessandro Albino;Silva, Márcio Lopes da;Valverde, Sebasti?o Renato;Souza, Agostinho Lopes de;
Revista árvore , 2003, DOI: 10.1590/S0100-67622003000400012
Abstract: forest activity was studied in vi?osa-mg, through a questionnaire applied to farmers who planted forests. a total of 63 farms were sampled, comprising an area of 2,096.95 ha. the natural and planted forest areas sampled were of 372.00 ha and 260.17 ha, corresponding to 17.74% and 12.41%, respectively. the predominant natural forest was the secondary forest (capoeira) (67.55%), and the species chosen for reforestation was eucalypt (92.68%). average labor use in the phases of implementation, maintenance and harvest of the forest plantations was estimated at 30.21, 13.64 and 61.25 days-man/hectare, respectively, totalling 105.10 days-man/hectare, with family labor participation of 25.24%. forest activity costs (r$/ha) were estimated at r$419.30 for implementation; r$146.49 and r$80.34 for first and second year maintenance, respectively, and r$2.11/m3 for wood harvesting cost. the forest plantations are concentrated at the hillside areas and the average number of jobs generated by reforestation (eucalypt) was 0.042 jobs/hectare. it was concluded that, overall, reforestation was considered a rather unattractive activity, with typical forest properties remaining unidentified. thus, it is recommended the elaboration of public policies to encourage reforestation.
Solu??o de problemas de planejamento florestal com restri??es de inteireza utilizando busca tabu
Rodrigues, Flávio Lopes;Leite, Helio Garcia;Santos, Heleno do Nascimentos;Souza, Agostinho Lopes de;
Revista árvore , 2003, DOI: 10.1590/S0100-67622003000500013
Abstract: this work aimed to develop and test an algorithm based on tabu search (ts) metaheuristics; to solve problems of forest management with integer constraints. ts was tested in five problems containing between 12 and 423 decision variables subjected to singularity constraints, minimum and maximum periodic productions. all the problems aimed at maximizing the net present value. ts was codified into delphi 5.0 language and the tests were performed in a microcomputer amd k6ii 500 mhz, ram memory 64 mb and hard disk 15gb. ts performance was evaluated according to efficacy and efficiency measures. the different values or categories for the ts parameters were tested and compared to their effects on algorithm efficacy. the best configuration of the parameters was selected by applying the l&o test at 1% probability and analyses via descriptive statistics. the best parameter configuration provided ts an average efficacy of 95.97%, a minimum value equal to 90.39%, a maximum value equal to 98.84%, with a variation coefficient of 2.48% of the mathematical optimum. for the most complex problem, ts efficiency of the exact algorithm branch and bound. thus, ts is a rrather attractive approach to solving important forest management problems.
Análise da atividade florestal no município de Vi osa-MG
Fontes Alessandro Albino,Silva Márcio Lopes da,Valverde Sebasti?o Renato,Souza Agostinho Lopes de
Revista árvore , 2003,
Abstract: Estudou-se a atividade florestal no município de Vi osa-MG, a partir de questionário aplicado aos agricultores cujas propriedades rurais possuíam florestas plantadas. Foi amostrado um total de 63 propriedades rurais, abrangendo uma área de 2.096,95 ha. As áreas de floresta nativa e plantada, na amostra, foram de 372,00 e 260,17 ha, o que corresponde, respectivamente, a 17,74 e 12,41% da área amostrada. O tipo de floresta nativa predominante foi a capoeira (67,55%), e a espécie preferida para o reflorestamento foi o eucalipto (92,68%). O uso médio da m o-de-obra nas fases de implanta o, manuten o e colheita dos plantios florestais foi estimado em 30,21, 13,64 e 61,25 dias-homem/ha, respectivamente, totalizando 105,10 dias-homem/ha, sendo a participa o da m o-de-obra familiar de 25,24%. Os custos inerentes à atividade florestal foram estimados em R$419,30/ha para implanta o; R$146,49/ha e R$80,34/ha para manuten o no primeiro e segundo ano, respectivamente; e R$2,11/m3 para colheita da madeira. Os plantios florestais concentram-se nas áreas de encostas, e o número médio de empregos gerados pelo reflorestamento (eucalipto) foi 0,042 emprego/ha. Concluiu-se, de modo geral, que o reflorestamento é considerado atividade pouco atrativa, n o identificando propriedades tipicamente florestais, sendo recomendada a elabora o de políticas públicas de incentivo ao reflorestamento.
Solu o de problemas de planejamento florestal com restri es de inteireza utilizando busca tabu
Rodrigues Flávio Lopes,Leite Helio Garcia,Santos Heleno do Nascimentos,Souza Agostinho Lopes de
Revista árvore , 2003,
Abstract: Este trabalho teve como objetivos desenvolver e testar um algoritmo com base na metaheurística busca tabu (BT), para a solu o de problemas de gerenciamento florestal com restri es de inteireza. Os problemas avaliados tinham entre 93 e 423 variáveis de decis o, sujeitos às restri es de singularidade, produ o mínima e produ o máxima periódicas. Todos os problemas tiveram como objetivo a maximiza o do valor presente líquido. O algoritmo para implementa o da BT foi codificado em ambiente delphi 5.0 e os testes foram efetuados em um microcomputador AMD K6II 500 MHZ, com memória RAM de 64 MB e disco rígido de 15GB. O desempenho da BT foi avaliado de acordo com as medidas de eficácia e eficiência. Os diferentes valores ou categorias dos parametros da BT foram testados e comparados quanto aos seus efeitos na eficácia do algoritmo. A sele o da melhor configura o de parametros foi feita com o teste L&O, a 1% de probabilidade, e as análises através de estatísticas descritivas. A melhor configura o de parametros propiciou à BT eficácia média de 95,97%, valor mínimo igual a 90,39% e valor máximo igual a 98,84%, com um coeficiente de varia o de 2,48% do ótimo matemático. Para o problema de maior porte, a eficiência da BT foi duas vezes superior à eficiência do algoritmo exato branch and bound, apresentando-se como uma abordagem muito atrativa para solu o de importantes problemas de gerenciamento florestal.
RELATIVE PRICE AND COMPETITIVENESS OF PLYWOOD INTERNATIONAL MARKET
Rommel Noce,Márcio Lopes da Silva,Lourival Marin Mendes,Agostinho Lopes de Souza
CERNE , 2007,
Abstract: This study analyzed Brazilian performance in the plywood international market. Specially to verify the relative price of Brazilian plywood as compared to the prices practiced by the main international player's and to decompose its performance in the international scenery in destiny effect, market growth effect and competitiveness effect from 1998 to 2002 period. It was noticed that the positioning of the prices as compared to the main exporters composes, in a decisive way, the competitiveness effect for the national industry of laminated panels and that Brazil was shown competitive in from 1998 to 2000 with a significant effect favorable competitiveness.
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