ABSTRACT The objective of this study was to compare different alternatives to estimate the stem volume of individual trees in four different forest formations in the Minas Gerais state, Brazil. The data were obtained in a forest inventory procedure performed by the Minas Gerais Technological Center Foundation. The stem volumes were computed by the Smalian expression up to the outside bark diameter equal to 4 cm. The volume data of outside bark, diameters (DBH) and total heights were used to fit a Schumacher and Hall equation for each forest formation, considering the structures of the linear fixed and mixed models. Next, 100 Multilayer Perceptron artificial neural networks (ANN) were trained in a supervised manner. In addition, we evaluated eight support-vector machine regression (SVMR). The criteria to evaluate the performance of all the alternatives studied were: the correlation between the observed and estimated volumes, the square root of the mean square error and the frequency distribution by percentage relative error class. After the analyzes, all the alternatives were verified to estimate the volume of the individual trees in the different forest formations. Although the alternatives presented close statistics in the validation process, the graphical analysis of the error distribution showed greater precision of the estimates of the mixed linear models for the four formations. Given the results, it is concluded that there is no absolute superiority of one alternative over the others, and that all of them should be evaluated to find the one which best describes or explains the dataset.

Abstract The objective of this study was to assess and compare two methodologies to predict the mortality of individual trees in a seasonal semi-deciduous forest located in the municipality of Viçosa, Minas Gerais, Brazil. The data came from 10 permanent plots and were randomly divided into two groups: fitting (6 plots) and validation (4 plots). When assessing Methodology 1, the mortality was considered a dichotomous variable in a logistic model, assuming a value of 1 for a dead tree and 0 for a living tree. In Methodology 2, the mortality probability was estimated by the group of trees for each plot and for each measurement interval. After the analysis, it was observed that Methodology 2 provided more consistent mortality estimates when compared to the mortality estimated by Methodology 1.

Resumo Estudos sobre a estrutura vegetacional de fragmentos florestais que consideram o uso pretérito do solo podem contribuir para subsidiar ações conservacionistas e de restauração florestal. A partir disso, objetivamos comparar três sítios de um fragmento florestal com distintas histórias de perturbação e verificar se os mesmos diferem entre si com relação ao estágio sucessional analisando atributos estruturais da vegetação arbórea e abundância de lianas. A área estudada localiza-se no município de Alegre-ES, em uma Floresta Estacional Semidecidual constituída por três sítios com diferentes históricos de uso do solo e idades de pousio que recuperaram-se de corte seletivo (CS), lavoura de café (CC) e pastagem (PA). Utilizamos parcelas (19) de área fixa (20 × 20 m) na amostragem, totalizando 0,76 ha. Os indivíduos arbóreos com DAP ≥ 5 cm e as lianas com DAP ≥ 1 cm foram amostrados. A análise da categoria sucessional demonstrou que os sítios CS e PA possuem estágio mais avançado de sucessão em relação à CC. A espécie de maior VI, síndromes de dispersão e lianas apontaram maior avanço sucessional do sítio PA, área com maior proteção aos efeitos de borda e antrópicos por estar localizada no interior do fragmento florestal. As demais análises não demonstraram diferença entre os três sítios.

Abstract To consider past land use on vegetative structure studies of forest fragments can contribute to conservation and forest restoration actions. From this we aim to compare three sites of a forest fragment with distinct anthropogenic disturbances and to verify if they differ on successional stage through analyses of structural traits (trees) and non-trees abundance (lianas) The studied area is located in the Alegre municipality, ES state, in a semideciduous seasonal forest matrix with different land use history composed of selective cutting (CS), coffee crop (CC) and pasture (PA). At each site, randomly plots were sample (19 total plots, 20 × 20 m each), totaling 0.76 ha. All tree individuals with DBH ≥ 5 cm and liana with DBH ≥ 1 cm were sampled. The successional category showed an advanced stage of succession in the CS and PA sites. The specie with higher VI, the dispersion syndromes and the abundance of lianas showed successional advanced stage only in the PA site, because is located inside the forest fragment providing greater protection from edge effects, and anthropogenic disturbances. The others analyses didn´t showed statistical differences between the three sites.

ABSTRACT This paper aimed to estimate the basic density (DB) of the wood of Cerrado species using mixed linear models. For performing the DBH measurement, the sampling of 334 individuals was carried out. By keeping the Pilodyn apparatus in the DBH position, two measurements were made on opposite sides. Further, for determining DB, the trees were knocked down, followed by removal of five wood discs at different height of stem positions. For this purpose, two sets of modeling alternatives were proposed, which take into account with and without random effects, employing species as a random effect grouping variable. Thus, it was elucidated that, for the estimation of DB, the mixed model that considered the random effects performed better as compared to the alternative model without random effects. The inclusion of random effects leads to the estimation of DB with high accuracy.

ABSTRACT The aim of this study was to evaluate the effects of age, site, and density factors on the dynamics of eucalyptus diameter distribution. Data were obtained from a continuous forest inventory measured at different occasions, stratified according to the factors evaluated and adjusted by the three-parameter Weibull function using nonthinned clonal plots of eucalyptus stands located in the Central region of the state of Minas Gerais. In order to evaluate the diameter distribution behavior, asymmetry and kurtosis measures and graphical analysis for fitted curves were used. In general, an increase was observed in diameter amplitudes with aging, as well as with improvement of site productivity and higher densities. The number of trees decreased in the lower classes and increased in the upper classes, resulting in diameter distribution curves, being displaced to the right and flattened with aging.

ABSTRACT The objective of this study was to evaluate the use of the MSI Sentinel-2 and SRTM data to estimate the volume of wood in a Semidecidual Seasonal Forest. Regression equations were fitted based on the remote sensing data, taking into consideration the individual bands and vegetation index of the MSI, elevation values and their derivatives obtained from the SRTM mission and the combination of the data drawn from the MSI and SRTM. RMSE and graphic analysis of residues were used to assess the accuracy of the fitted equations. The best model revealed values of 0.6508 and RMSE of 20.41% in the fit, and of 0.5680 and RMSE of 26.61% in the validation, using the combined MSI and SRTM data as predictors. The volume estimation using spectral data showed satisfactory results, highlighting the importance of topography in the prediction of the volume of wood for the area under investigation.

ABSTRACT: The main purpose of this study was to assess nonlinear models generated by integrating the basal area growth rate to estimate the growth and yield of forest stands. The database was collected from permanent sample units, in Paraopeba county, in the state of Minas Gerais, Brazil. The stands were represented by Eucalyptus camaldulensis × Eucalyptus urophylla hybrid trees, with 3 × 3 meters of spacing. The data were divided into two groups: fitting and validating databases. Two nonlinear models (Strategy A and Strategy B) were developed using differential equations to estimate the basal area growth and yield of the sample units. The logistic model was fitted to estimate the volumetric yield as a function of age, site index and basal area. The efficiency of the systems generated by logistic model and models obtained by differential equations (Strategy A and Strategy B) was also compared to the efficiency of the system estimated by the Clutter model (Strategy C). The projection models used to estimate basal area obtained by differential equations were compatible with forest growth and yield, and the logistic model with covariates was compatible with volumetric growth and yield. Strategy A and Strategy B generated different thinning and harvesting options for different site indices, which is biologically consistent.

RESUMO O objetivo geral deste trabalho foi avaliar o método Neuroevolution of Augmenting Topologies (NEAT) para ajustar os pesos e a topologia de redes neurais artificiais (RNAs) na estimação da altura de árvores em povoamento clonais de eucalipto, bem como comparar com as estimativas obtidas por um modelo hipsométrico de regressão. Para a estimativa da altura total das árvores (Ht), pelas RNAS e pelo modelo de regressão, utilizou-se variáveis diâmetro à 1,3 m de altura (dap) e a altura dominante (Hd). As RNAs foram ajustadas e aplicadas no sistema computacional NeuroForest, variando o tamanho da população inicial (parâmetro do algoritmo genético) e a densidade das conexões iniciais. As estimativas da altura total das árvores obtidas com o emprego de RNA e pelo modelo de regressão foram avaliadas com base no coeficiente de correlação, no gráfico de dispersão dos erros percentuais, no histograma de frequência percentual dos erros percentuais e na raiz do erro quadrado médio percentual (Root Mean Square Error - RMSE). A configuração de tamanho de população 300 e densidade inicial das conexões de 0,1 obteve a maior correlação e o menor RMSE%. Foram encontradas várias configurações de RNA com estatísticas superiores ao modelo hipsométrico de regressão. A metodologia NEAT pode ser utilizada para a estimação da altura de árvores em povoamento clonais de eucalipto.

ABSTRACT The aim of this study was to evaluate the method of neuroevolution of augmenting topologies (NEAT) to adjust the weights and the topology of artificial neural networks (ANNs) in the estimation of tree height in a clonal population of eucalyptus, and compare with estimates obtained by a hypsometric regression model. To estimate the total tree height (Ht), the RNAs and the regression model, we used as variables a diameter of 1.3 m height (dbh) and the dominant height (Hd). The RNAs were adjusted and applied to the computer system NeuroForest, varying the size of the initial population (the genetic algorithm parameter) and the density of initial connections. Estimates of the total height of the trees obtained with the use of RNA and the regression model were evaluated based on the correlation coefficient, the percentage of errors scatter plot, the percentage frequency histogram of percentage errors, and the root mean square error (root mean square error - RMSE). Various settings which resulted in superior statistics to the hypsometric regression model were found. Connections had the highest correlation and the lowest RMSE% with a population size value of 300 and an initial density of 0.1 RNA. The NEAT methodology proved effective in estimating the height of trees in clonal population of eucalyptus.

RESUMO Objetivou-se aplicar e avaliar métodos para estimar múltiplos volumes em uma Área de Manejo Comunitário, localizada na Floresta Nacional do Tapajós. Foram cubadas, rigorosamente, 516 árvores-amostra de 21 espécies comerciais, todas com 50 cm > dap < 160 cm. Utilizaram-se o modelo único para múltiplos volumes (análise de regressão) proposto por Leite et al. (1995) e redes neurais artificiais (RNA) para a estimativa do volume de fuste e galhos. Após os resultados preliminares usando o método de regressão, optou-se por separar os dados em três estratos, considerando a relação volume de galhos em razão do volume de fuste comercial. As equações geradas por estratos apresentaram melhoria nos ajustes, mas os resultados obtidos pela RNA foram melhores que os pelas equações de regressão.

ABSTRACT The objective of this study was to apply and evaluate methods to estimate multiple volumes in a Community Management Area, located in the Tapajós National Forest. 516 sample-trees were rigorously scaled of 21 commercial species, all with 50 cm > dbh < 160 cm. The unique model for multiple volumes (regression analysis) proposed by Leite et al. (1995) and Artificial Neural Networks (ANN) were used to estimate the volume of stem and branches. After preliminary results using the regression method, it was decided to stratify the data into three parts, considering the relationship between volume of branches and volume of commercial stem. The equations generated showed improvement in the adjustments. However, the results with ANN were better than the ones generated by regression equations.

O objetivo deste estudo foi avaliar o rendimento em laminação de madeira de paricá (Schizolobium amazonicum Huber ex. Ducke) em plantios comerciais na região de Paragominas, Pará. A partir de 180 árvores-amostra oriundas de plantios com idades de cinco, seis e sete anos em espaçamento 4 x 4 m, foram avaliados o rendimento médio na atividade levando em consideração os rendimentos por idade e por classe de diâmetro. Foram avaliadas também as perdas em todo o processo de laminação. Os resultados apontaram um rendimento médio de 50,31% na atividade, o que é compatível com espécies dos gêneros Pinus e Eucalyptus. Verificou-se que as árvores com maior idade e diâmetro apresentaram os maiores rendimento e, consequentemente, as menores perdas devido a defeitos e ao rolo-resto.

The aim of this study was to evaluate the performance of laminate wood paricá (Schizolobium amazonicum Huber ex. Ducke) in commercial plantations in the region of Paragominas, Pará state. Using 180 sample trees aged five, six and seven years,originating from plantations and grown in 4 x 4 m spacing, the average income was evaluated, taking into account income by age and diameter class. Losses were also evaluated throughout the lamination process. The results show an average yield of 50.31% in the activity, which is consistent with species of Pinus and Eucalyptus. Trees that were older and larger in diameter showed higher yield and therefore lower losses due to defects and the remainder roller.

Objetivou-se, neste trabalho, avaliar a dinâmica do estoque de carbono no fuste das árvores de uma Floresta Estacional Semidecidual, por meio do monitoramento de 10 parcelas permanentes instaladas na Mata da Silvicultura, Viçosa, Minas Gerais. Foram identificados e medidos todos os indivíduos com DAP ≥ 5 cm, nos anos de 1994, 1997, 2000, 2004 e 2008. O estoque médio de carbono no fuste das árvores aumentou de 47,9 ton.ha-1, no ano de 1994, para 61,81 ton.ha-1, no ano de 2008, representando, para os 14 anos de monitoramento, um incremento periódico de 0,994 ton.ha-1.ano-1.

The objective of this study was to evaluate the dynamics of stem carbon storage in a Semideciduous Forest, through the monitoring of 10 permanent plots established in the Mata da Silvicultura, Viçosa, Minas Gerais. All trees with DBH ≥ 5 cm were identified and measured in the years 1994, 1997, 2000, 2004 and 2008. The stems average carbon storage increased 47.9 ton.ha-1 from the year of 1994 to 61.81 ton.ha-1 in the year of 2008, representing, for the monitoring of 14 years, a regular increase of 0.994 ton.ha-1.year-1.

O objetivo deste estudo foi avaliar o crescimento de espécies florestais nativas mediante a utilização de diferentes métodos de restauração florestal e submetidas a diferentes técnicas de manutenção, em uma Mata de Tabuleiros. O experimento foi instalado em agosto de 2007, na Reserva Natural Vale (RNV), Linhares, ES, em blocos casualizados que consistiram em quatro tratamentos e três repetições, sendo: T1 (Controle) controle de formigas-cortadeiras; T2 capina química seletiva e controle de formigas e das espécies tolerantes ao herbicida; T3 Idem ao T2 + plantio de 14 espécies pioneiras da Mata Atlântica (espaçamento: 5 x 5 m) intercalado com semeio de Sesbania grandiflora em covas; e T4 Idem ao T2 + plantio de 54 espécies da Mata Atlântica (3 x 3 m). Foram medidos e identificados os indivíduos com DAP ≥ a 5 cm, no momento da implantação do experimento e nos três anos posteriores. No terceiro ano, também foi coletado o IAF. As famílias mais ricas em espécies no terceiro ano de estudo foram Fabaceae, Anacardiaceae e Lecythidaceae, sendo somente no T4 observadas espécies nos quatro grupos ecológicos. O maior índice de área foliar foi observado no T3, indicando maior sombreamento da área. O ingresso de número de indivíduos e de área basal foi superior nos T3 e T4, sugerindo maior crescimento da vegetação, em que houve plantio de mudas. De forma geral, a eliminação da matocompetição atuou positivamente no crescimento da vegetação arbórea.

The aim of this study was to evaluate the growth of native forest species using different forest restoration methods and under different maintenance techniques, in a Tableland Forest. The experiment was installed in August 2007 in ‘Reserva Natural Vale (RNV), Linhares, ES, in a randomized blocks that consisted of 4 treatments and 3 replications: T1 (control) ants control; T2 selective chemical weeding, ants control and control of herbicide tolerant species; T3 same as T2 + planting of 14 pioneer species of the Atlantic Rainforest (spacing: 5 x 5 m) and intercalated seeding of Sesbania grandiflora in pits; and T4 same as T2 + planting of 54 species of the Atlantic Rainforest (3 x 3 m). Plants with DBH ≥ 5 cm were measured and identified at the time of the installation of the experiment and the three subsequent years. In the third year the IAF was also collected. The richest families in species in the third year of study were Fabaceae, Anacardiaceae and Lecythidaceae, and only in T4 species were observed in the four ecological groups. The higher leaf area index was observed in T3, indicating greater shading area. The ingrowth of plants and basal area was higher in T3 and T4, suggesting greater vegetation growth, where seedlings were planted. In general, the elimination of weed competition worked positively in the tree growth.

Objetivou-se, no presente trabalho, avaliar modelos para estimar a produção de sortimentos de plantios clonais do híbrido Eucalyptus camaldulensis x Eucalyptus urophylla com espaçamento 3 x 3 m, localizados em Paraopeba, Minas Gerais, Brasil. Para estimar a produção em área basal e volume dos sortimentos de povoamentos, foram utilizados dados parcelas permanentes. Para estimar o volume dos sortimentos, foram analisados o modelo logístico com adição de covariáveis e o modelo de Clutter. Para a seleção do modelo mais preciso, foram utilizadas as estatísticas erro padrão relativo [Syx (%)], viés (V), média das diferenças (MD), desvio padrão das diferenças (DPD) e análise gráfica dos resíduos. De acordo com as análises, o modelo Logístico obteve o melhorresultado para estimar a produção em volume de madeira para energia e celulose. A metodologia de estimação da produção de sortimentos de plantações florestais analisada foi de fácil aplicação e precisa.

The aim of this study was to evaluate models to estimate the assortment yield of clonal Eucalyptus camaldulensis x Eucalyptus urophylla hybrid plantations with 3 x 3 m spacing in the Paraopeba city, Minas Gerais, Brazil. To estimate basal area and volume of the assortment yield data from permanent plots was used. To estimate the volume of assortments, we analyzed the logistic model with covariates and the Clutter model. The statistical standard error [Syx (%)], bias (V), average of the differences (MD), and standard deviation of the differences (DPD), as well as the graphical analysis of the residuals were used to select the most accurate model. According to the analysis, the Logistic model obtained the best results for estimation of the yield in wood volume for energy and pulpwood. The methodology to estimate assortment of forest plantations was considered easy to use and accurate.

The diameter and height growth model is one of three submodels used for simulating individual tree growth. In Brazil, there are few studies on the dimensional growth of individual trees be they native or exotic species, despite their potential. This study aimed to evaluate diameter and height growth models for individual trees for eucalyptus stands and to validate the best fitting model. Tree diameter and height data were obtained from 48 permanent plots of unthinned stands of Eucalyptus grandis × Eucalyptus urophylla hybrid located in northern Brazil. The evaluation of the diameter and height growth models was based on adjusted coefficient of determination, standard error of estimate as a percentage, trend, root mean square error and Akaike Information Criterion. Analysis also included distribution of residual percentage, statistical significance and signs of the coefficients. The Lundqvist-Korf model provided the most accurate estimates for diameter and height growth, in comparison with the other models, providing better statistical values, greater proximity to observed values and better distribution of residual percentages. The use of this type of model is feasible and can result in significant improvements in the accuracy of yield estimates.

RESUMO O presente estudo foi realizado em um fragmento de Floresta Estacional Semidecidual de 52 ha, conhecido como Floresta do Rosal, no município de Guaçuí-ES e teve como objetivo testar metodologias de estratificação vertical, avaliando a adequação dessas metodologias baseada na classificação sucessional ecológica das espécies. Para tanto, empregou-se o método de amostragem de área fixa, sendo distribuídas 16 parcelas de 600 m2, de forma sistemática no campo. Todos os indivíduos com DAP ≥ 5 cm tiveram suas alturas totais medidas de forma direta. As árvores passaram por processo de identificação botânica e classificação quanto ao grupo ecológico. A análise da estrutura vertical de espécies arbóreas foi feita pela distribuição do número de árvores nos estratos, utilizando-se quatro métodos: Método 1 - Souza (1990), Método 2 - Souza et al. (2003), Método 3 - IUFRO, e Método 4 - Calegário et al. (1994). Os resultados das classificações obtidas foram comparados à classificação sucessional das espécies, de acordo com os grupos ecológicos a que pertencem. O Método 1 não permitiu análise detalhada sobre o comportamento das espécies no estrato II por apresentar tendências fortes em concentrar um maior número de indivíduos no referido estrato, já o Método 2 permitiu um maior detalhamento. O Método 3 minimizou o problema encontrado no Método 1, porém, a mudança da altura dominante da amostragem pode mudar toda a discussão, demonstrando fragilidade do método. O Método 4 não trouxe bons resultados para a estratificação da floresta em estudo, pois a dividiu em apenas dois estratos de altura total.

ABSTRACT This study was conducted in a semideciduous forest fragment of 52 hectares, known as Rosal Forest, in the municipality of Guaçuí, Espírito Santo state. It had the objective to test vertical stratification methodologies, evaluating the appropriateness of these methodologies based on the ecological successional classification of the species. To do so, the method of sampling fixed area was used, and distributed 16 plots of 600 m², in a systematic way. All individuals with DBH ≥ 5 cm, had their total height measures directly. The trees went through the botanical classification identification process and had their classifications in accordance with their ecological groups. The analysis of the tree vertical structure was made by the distribution of the number of trees in the strata, using four methods: Method 1 - Souza (1990), Method 2 - Souza et al. (2003), Method 3 - IUFRO, and Method 4 - Calegário et al. (1994). The classification results were compared to the successional classification of species, according to the ecologic groups that they belong to. The method 1 did not allow a detailed analysis about the behavior of stratum II species, because of the strong tendencies to concentrate a greater number of individuals in this stratum, already the Method 2 has allowed a greater detail. The Method 3 minimized the problem encountered in Method 1, but the dominant height change of the sample can change the whole discussion, demonstrating the method weakness. Method 4 did not bring good results for the forest stratification under study, because this method only divided in two height strata.