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Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this work was to analyze the legal arrangements on a very complex theme in the forest sector: the use of a species threatened with extinction, araucaria. After years of intense deforestation, linked to the country's economic growth, after 1960 decade, it was edited an array of regulations aimed to control the forest use through strict laws and expansion of the environmental bureaucracy. In 2014, MMA Decree 443, araucaria was included in the danger category, restricting any timber use, including the ones gathered under forest management. The justification for this inclusion comes from the population reduction, deforestation and logging. Regarding the justification of its inclusion, it is important to note the non-disclosure of official data, an obligation of the State, on the remaining area and number of individuals. Decree 443 collides with the Brazilian forest low removing rights, as forest management, not established by Law number 12.651 of 2012. It also defies the Complementary Law 140 which establishes reports and technical-scientific studies for framing the listed species. Nor does it comply with the steps required in article 5° MMA Decree 43, which precedes Decree 443. By analyzing the regulations regarding the araucaria and its commercial use: there is no law prohibiting the use, through management and planting; what exists are Decrees and resolutions. Whoever is in the messianic right to forbid the cutting of the species, subsidizes itself in Decrees and resolutions. Moreover, who believes they have the right to cut it, is not aware of the legislation. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the effectiveness of artificial neural networks (ANNs) and mixed-effects models (MEMs) in describing the stem profile of Pinus taeda L., using sample data from 246 trees. First, three taper functions of different classes were adjusted: non-segmented, segmented, and variable-form. To adjust the models, the nonlinear regression technique (nls) was used. In the best performance equation for nls-adjusted diameter estimates, the nonlinear MEM (nlme) was applied at two levels, using the age class (ci) and DBH class (cd). For this, three different study scenarios were considered, with the number of coefficients with random effects ranging from one to three in each scenario. The adjustments were made using the nls and nlme functions in R software. The selected mixed-effect equations were compared with ANNs generated in Neuro 4.0 software. The taper function models and ANNs were classified according to statistical criteria and graphical analysis of residues. The tapering equation of Bi (2000) presented better performance for diameter estimates than the non-segmented and segmented equations. Application of the nlme technique in the Bi (2000) equation increased the accuracy of the diameter estimates for Pinus taeda, in relation to the adjustment using the nls technique. In the comparison of ANNs with the variations of the Bi equation of mixed-effects, the networks performed better, indicated in the description of the P. taeda profile. [ABSTRACT FROM AUTHOR]

The costs related to forest harvesting and wood transport are key to the economic viability of forest investments. These operations compose a major share of the total cost of wood production and thus need to be conducted in an efficient manner. In this paper, we propose a novel optimization model to tackle this issue and perform the daily and weekly plan of harvesting operations, in order to minimize the costs related to the machinery operation, movement, and wood transportation, subject to demand constraints. Our results show that transportation costs dominate the total cost of these operations. The model proposed is appropriate and can be effectively applied to optimize the operational planning of harvesting activities. Nevertheless, instances with a large number of stands may lead to a substantial increase in the complexity and computational burden. We conclude that operations research techniques can provide a solid basis for decision-making in harvest scheduling problems and increase the efficiency of forest management. [ABSTRACT FROM AUTHOR]

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper aims to evaluate and compare the mixed effects modeling and artificial neural networks in order to estimate the taper of eucalyptus in integrated Crop-Livestock-Forestry (iCLF) systems. The data were collected in an experimental area of iCLF, implanted by the Brazilian Company of Farming Research – EMBRAPA Agrossilvipastoril, located in the municipality of Sinop, Mato Grosso State, Brazil. To reach the proposed aim, 165 trees with 51 months of age were scaled for the taper modeling with mixed effects models and artificial neural networks. The performance of these techniques was evaluated through precision measurements and graphical analysis. Mixed effects modeling and artificial neural networks are efficient and recommended in the estimative of taper of eucalyptus in integrated Crop-Livestock-Forestry system; however, despite both evaluated techniques present accurate results in predicting the taper of the sampled trees, the artificial neural network predicts values with greater precision than the modeling of mixed effects. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ceres is the property of Revista Ceres and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Scientia Agraria Paranaensis is the property of Revista Scientia Agraria Paranaensis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Este trabalho teve como objetivo desenvolver um Diagrama de Manejo da Densidade (DMD) para definir momentos ótimos para aplicação de desbastes e corte final em povoamentos de Pinus taeda L., no estado do Paraná. A base de dados utilizada no estudo é oriunda de plantios de Pinus taeda estabelecidos no estado do Paraná, nas regiões Centro-Oeste, Sul e Campos Gerais, além de dados coletados na Floresta Nacional de Irati (FLONA de Irati) e em um experimento com diferentes espaçamentos existente no Campus da UNICENTRO (Universidade Estadual do Centro-Oeste), no município de Irati. Foram utilizadas 1.023 parcelas sem desbastes, com idades variando de 7 a 44 anos. Foi ajustado o modelo de densidade de Reineke (1933) para obter o Índice de Densidade de Reineke (IDR), construindo-se então, o DMD similarmente à metodologia proposta por McCarter e Long (1986) e Dean e Baldwin (1993), o qual tem como componentes básicos o IDR e um sistema de equações que relacionam o diâmetro médio quadrático (dg) e o volume do povoamento (V) com a densidade (N), altura dominante (hdom) e o diâmetro médio quadrático. O sistema de equações ajustado para a construção do DMD apresentou estatísticas adequadas de ajuste e precisão, possibilitando a definição das densidades iniciais para atingir um dado diâmetro de tamanho desejado no corte final, bem como conhecer as idades em que devem ser realizadas as intervenções e a prognose da produção de cada colheita. Palavras-chave: Autodesbaste; desbastes; manejo intensivo. This work aimed to develop a stand density management diagram (SDMD) to define the best thinning schedule on Pinus taeda L. stands. The database used in the study came from Pinus taeda plantations established in state of Paraná, Brazil, in the Midwest, South and Campos Gerais regions, besides data collected from the National Forest of Irati and from an experiment with different spacings located on the campus of the State University of Midwest, in municipality of Irati. We used 1,023 plots without thinnings, with ages ranging from 7 to 44 years. Reineke density model (1933) was adjusted to obtain the Reineke Density Index (RDI), constructing then the DMD similarly to the methodology proposed by McCarter and Long (1986) and Dean and Baldwin (1993), which has as basic components, the IDR and a system of equations that relates the quadratic mean diameter (dg) and the stand volume (V) with the density (N), dominant height (hdom) and the quadratic mean diameter. The system of equations fitted for the construction of the DMD presented appropriate statistical adjustment and accuracy, allowing the definition of the initial densities to achieve a given diameter of the desired size in the clearcutting, as well as knowing the ages in which interventions should be carried out and prognosis of production of each harvest. [ABSTRACT FROM AUTHOR]