DIVERSIDADE FLORÍSTICA E EQUABILIDADE EM FRAGMENTOS FLORESTAIS USANDO REDES NEURAIS ARTIFICIAIS

This study aimed to evaluate the predictive efficiency of Shannon index (H') and Pielou Equitability index (J) in forest fragments from the Brazilian Cerrado biome, from the vegetation indices and landscape metrics using artificial neural networks (ANN). Feedforward networks were used and they were trained through a back propagation error algorithm. The variables used as ANN input for simultaneous estimation of indices were: the categorical (H' and J) and the numbers related to the mean and standard deviation of vegetation indices (NDVI, SAVI, EVI, and MVI5, MVI7) and landscape metrics (AREA, GYRATE, SHAPE, CONTIG, CORE and ENN). It was generated five models of ANN from the functional relationships between numerical variables inherent to vegetation indices in two seasons, a dry season (June) and a rainy season (February). The architecture of the networks was the Multilayer Perceptron (MLP), to estimate simultaneously the H' and J: 500 using vegetation indices in the wet season (100 for each vegetation index) and 500 in dry (100 for each vegetation index). The precision, accuracy and realism of biological ANN were assessed. The nets built during the rainy season and dry season that used vegetation indices MVI5 (Moisture Vegetation Index) and SAVI (Soil Adjusted Vegetation Index), respectively, were more appropriate, accurate and biologically realistic to estimate both indices H' and J. The ANN modeling demonstrated to be adequate to estimate the diversity index.Este estudo teve como objetivo avaliar a eficiência da predição dos índices de diversidade de Shannon (H’) e de Equabilidade de Pielou (J) em fragmentos florestais do Cerrado brasileiro a partir de índices de vegetação e métricas da paisagem empregando redes neurais artificiais (RNA). Utilizaram-se redes anteroalimentadas (feedforward), treinadas por meio do algoritmo da retropropagação do erro (back propagation). As variáveis utilizadas como entradas das RNA para a estimação simultânea dos índices foram: as categóricas (índices H’ e J) e as numéricas relacionadas às médias e desvios padrão dos índices de vegetação (NDVI, SAVI, EVI, MVI5 e MVI7) e métricas da paisagem (AREA, GYRATE, SHAPE, CONTIG, CORE e ENN). Foram gerados cinco modelos de RNA a partir das relações funcionais entre as variáveis numéricas inerentes aos índices de vegetação em duas épocas, uma seca (junho) e outra chuvosa (fevereiro). A arquitetura das redes foi a Multilayer Perceptron (MLP) para estimar simultaneamente H’ e J: 500 utilizando os índices de vegetação na época úmida (100 para cada índice de vegetação) e 500, na seca (100 para cada índice de vegetação). Foi avaliada a precisão, acurácia e realismo biológico das RNA. As redes construídas na época chuvosa e seca que utilizaram os índices de vegetação MVI5 (Moisture Vegetation Index) e SAVI (Soil Adjusted Vegetation Index), respectivamente, foram mais adequadas, precisas e realistas biologicamente para estimar, simultaneamente, os índices de H’ e de J. A modelagem por RNA demonstrou-se adequada para estimar os índices de diversidade e equabilidade

Caracterização florística e estrutural de fragmentos de Matas de Galeria da Bacia do Alto Araguaia

http://dx.doi.org/10.5902/1980509814575The forests of upper Araguaia river basin are daily exposed to degradation agents due to intense agriculture practices. Twenty two fragments (of 10 until 169 ha) were surveyed according to point-centered quarter method to characterize vegetation structure and to create a database to forest restoration. One hundred and nine (109) species, belonging to 78 genus and 42 families, were sampled where 73.4% revealed zoochorous dispersal pattern, and 69.7% were classified to initial sucessional category. Shannon index and Pielou equability index were 3.86 nats. ind-1 and 0.82, respectively. Density and total basal area estimated were 1,351 trees.ha-1 and 19.28 m2.ha-1. The areas showed lower richness, Shannon and Pielou heterogeneity indices, lower basal area, and high number of species of intermediate stage of ecological sucession and colonization of cerrado and cerradão species in disturbed areas, altering the original landscape. Such situation, added to the importance of those areas for the biodiversity conservation and ecological services (mainly relative to the water), demands protection actions and management that use the great regenerative potential of the area, given by the existence of a great number of initial secondary species and the prevalence of zoochoric species.http://dx.doi.org/10.5902/1980509814575As florestas da bacia do alto Araguaia estão diariamente expostas a vários agentes de degradação devido à intensa prática de agricultura nessa região. Vinte e dois fragmentos (de 10 a 169 ha) foram inventariados pelo método de quadrantes centrados, com o objetivo de caracterizar a estrutura da vegetação e criar um banco de dados de informações voltado para programas de restauração florestal na região. Foram amostradas 109 espécies pertencentes a 78 gêneros e 42 famílias. Dessas, 73,4% apresentaram padrão de dispersão zoocórica e 69,7% foram classificadas como de estádios iniciais de sucessão (53,2% secundárias iniciais e 16,5% pioneiras). O índice de Shannon foi 3,86 nats.ind-1 e o de equabilidade de Pielou foi 0,82. As estimativas da densidade e área basal, considerando todos os fragmentos, foram de 1.351 árvores.ha-1 e 19,28 m2.ha-1, respectivamente. As áreas apresentaram uma menor riqueza (quando comparadas a matas de galerias mais conservadas), heterogeneidade nos índices de diversidade e equabilidade, tamanho reduzido das árvores e consequente baixa área basal, elevado número de espécies características de estádios intermediários de sucessão ecológica e colonização de espécies de cerrado e cerradão em áreas mais antropizadas, alterando a paisagem original. Tal situação, somada à importância dessas áreas para a conservação da biodiversidade e de serviços ecológicos (principalmente relativos à água), exige ações de proteção e manejo conservacionista que aproveitem o grande potencial regenerativo da área, dado pela existência de um grande número de espécies secundárias iniciais e predomínio das espécies zoocóricas

FLORISTIC AND STRUCTURAL CHARACTERIZATION OF GALLERY FOREST FRAGMENTS OF UPPER ARAGUAIA RIVER BASIN

As florestas da bacia do alto Araguaia est\ue3o diariamente expostas a v\ue1rios agentes de degrada\ue7\ue3o devido \ue0 intensa pr\ue1tica de agricultura nessa regi\ue3o. Vinte e dois fragmentos (de 10 a 169 ha) foram inventariados pelo m\ue9todo de quadrantes centrados, com o objetivo de caracterizar a estrutura da vegeta\ue7\ue3o e criar um banco de dados de informa\ue7\uf5es voltado para programas de restaura\ue7\ue3o florestal na regi\ue3o. Foram amostradas 109 esp\ue9cies pertencentes a 78 g\ueaneros e 42 fam\uedlias. Dessas, 73,4% apresentaram padr\ue3o de dispers\ue3o zooc\uf3rica e 69,7% foram classificadas como de est\ue1dios iniciais de sucess\ue3o (53,2% secund\ue1rias iniciais e 16,5% pioneiras). O \uedndice de Shannon foi 3,86 nats.ind-1 e o de equabilidade de Pielou foi 0,82. As estimativas da densidade e \ue1rea basal, considerando todos os fragmentos, foram de 1.351 \ue1rvores.ha-1 e 19,28 m2.ha-1, respectivamente. As \ue1reas apresentaram uma menor riqueza (quando comparadas a matas de galerias mais conservadas), heterogeneidade nos \uedndices de diversidade e equabilidade, tamanho reduzido das \ue1rvores e consequente baixa \ue1rea basal, elevado n\ufamero de esp\ue9cies caracter\uedsticas de est\ue1dios intermedi\ue1rios de sucess\ue3o ecol\uf3gica e coloniza\ue7\ue3o de esp\ue9cies de cerrado e cerrad\ue3o em \ue1reas mais antropizadas, alterando a paisagem original. Tal situa\ue7\ue3o, somada \ue0 import\ue2ncia dessas \ue1reas para a conserva\ue7\ue3o da biodiversidade e de servi\ue7os ecol\uf3gicos (principalmente relativos \ue0 \ue1gua), exige a\ue7\uf5es de prote\ue7\ue3o e manejo conservacionista que aproveitem o grande potencial regenerativo da \ue1rea, dado pela exist\ueancia de um grande n\ufamero de esp\ue9cies secund\ue1rias iniciais e predom\uednio das esp\ue9cies zooc\uf3ricas.The forests of upper Araguaia river basin are daily exposed to degradation agents due to intense agriculture practices. Twenty two fragments (of 10 until 169 ha) were surveyed according to point-centered quarter method to characterize vegetation structure and to create a database to forest restoration. One hundred and nine (109) species, belonging to 78 genus and 42 families, were sampled where 73.4% revealed zoochorous dispersal pattern, and 69.7% were classified to initial sucessional category. Shannon index and Pielou equability index were 3.86 nats. ind-1 and 0.82, respectively. Density and total basal area estimated were 1,351 trees.ha-1 and 19.28 m2.ha-1. The areas showed lower richness, Shannon and Pielou heterogeneity indices, lower basal area, and high number of species of intermediate stage of ecological sucession and colonization of cerrado and cerrad\ue3o species in disturbed areas, altering the original landscape. Such situation, added to the importance of those areas for the biodiversity conservation and ecological services (mainly relative to the water), demands protection actions and management that use the great regenerative potential of the area, given by the existence of a great number of initial secondary species and the prevalence of zoochoric species

Landscape structure analysis of the upper Araguaia river basin in the brazilian savanna

O Centro-Oeste brasileiro era extensivamente coberto por fitofisionomias de Savanas até o final da década de 1970, quando se iniciaram amplas transformações, devido à expansão da fronteira agrícola e modernização da agricultura, que promoveram desmatamento intensivo e rápido. A vegetação que resta hoje se encontra na forma de fragmentos, os quais podem sofrer vários efeitos que podem levar à diminuição ou desaparecimento de espécies. As mudanças ocorridas em uma paisagem podem ser estudadas pelos métodos da Ecologia da Paisagem, por meio da avaliação de índices ou métricas para caracterização quantitativa, permitindo também comparar paisagens, identificar diferenças e determinar relações entre os processos funcionais e os padrões dessas paisagens. O objetivo deste trabalho foi analisar a estrutura da paisagem na alta bacia do rio Araguaia, em cinco épocas (1977, 1989, 1997, 2002 e 2006) para avaliar o seu padrão de fragmentação ao longo do tempo após desmatamento intenso. Os resultados mostram que a metodologia utilizada foi satisfatória, a fragmentação revela notável taxa de conversão das fitofisionomias originais em favor de pastagem e agricultura e as métricas de área, área central, forma e isolamento, mostram que os fragmentos encontram-se sob forte ameaça em relação à sua integridade.Palavras-chave: Métricas da paisagem; Fragstats; fragmentação; integridade dos fragmentos. AbstractLandscape structure analysis of the upper Araguaia river basin in the brazilian savanna. The Central-West region of Brazil was extensively covered by Savanna physiognomies at the end of 1970`s, when large transformations, due to expansion of agriculture frontier and agriculture modernization, promoted an intensive and fast deforestation. The vegetation that remains today is in the fragments form, which can suffer several effects that can lead to the decrease or disappearance of species. The changes that occurred in a landscape can be studied through the methods of Landscape Ecology, by evaluating the indices or metrics for quantitative characterization, allowing to compare landscapes, identify differences and determine relationships between the functional processes and the patterns of those landscapes. The objective of this paper was to analyze the structure of the landscape in the upper Araguaia river basin, in five years (1977, 1989, 1997, 2002 and 2006), to evaluate its pattern of fragmentation along the time, after the intensive deforestation. The results showed that the methodology used was satisfactory. The fragmentation revealed notable rate of conversion of the original physiognomies in pasture and agricultural lands and the metrics of the area, core area, shape and isolation of the natural classes showed that the fragments, in relation to its integrity, are under strong threat.Keywords: Landscape metrics; Fragstats; fragmentation; fragments integrity.The Central-West region of Brazil was extensively covered by Savanna physiognomies at the end of 1970`s, when large transformations, due to expansion of agriculture frontier and agriculture modernization, promoted an intensive and fast deforestation. The vegetation that remains today is in the fragments form, which can suffer several effects that can lead to the decrease or disappearance of species. The changes that occurred in a landscape can be studied through the methods of Landscape Ecology, by evaluating the indices or metrics for quantitative characterization, allowing to compare landscapes, identify differences and determine relationships between the functional processes and the patterns of those landscapes. The objective of this paper was to analyze the structure of the landscape in the upper Araguaia river basin, in five years (1977, 1989, 1997, 2002 and 2006), to evaluate its pattern of fragmentation along the time, after the intensive deforestation. The results showed that the methodology used was satisfactory. The fragmentation revealed notable rate of conversion of the original physiognomies in pasture and agricultural lands and the metrics of the area, core area, shape and isolation of the natural classes showed that the fragments, in relation to its integrity, are under strong threat

Classificação da capacidade produtiva com alturas de árvores dominantes estimadas por RNA

The generation of site curves built from modeling the height of dominant trees measured in permanent plots at different ages considering a reference age constitutes the most practical and widespread method to classify the local productive capacity. Within a Forest Planning process, the assertiveness of the generated curves has quantitative and qualitative consequences in the allocation of resources, so that the continuous improvement of classification methods is of paramount importance. This study aimed to propose models of Artificial Neural Networks (ANN) to estimate the height of dominant eucalyptus trees, and apply them in the generation of site curves using the guide curve method, as an alternative to non-linear and assess the accuracy of estimates and stability of the classification of local productive capacity generated by these approaches. The data used are from measurements of 8,819 permanent plots installed in clonal stands of Eucalyptus urophylla × Eucalyptus grandis. Five classical non-linear models were fitted and the ANN were trained with two algorithms: Feed Forward Back Propagation Network (FFBP) and Cascade Forward Back Propagation Network (CFBP). In general, when only the age of the plots was used to estimate the dominant height, there was no difference in the results between the ANN trained with the two algorithms and the non-linear models. However, with the addition of new stand variables during ANN training, there was an improvement in estimates of dominant heights and generated a 13% more stable productive capacity classification compared to non-linear regression models.A construção de curvas de sítio a partir da modelagem da altura de árvores dominantes medidas em parcelas permanentes em diferentes idades, considerando uma idade de referência, se constitui no método mais prático e difundido no meio florestal para classificar a capacidade produtiva local. Dentro de um processo de Planejamento Florestal, o grau de assertividade das curvas geradas tem consequências quantitativas e qualitativas na alocação de recursos, de forma que a melhoria contínua dos métodos de classificação é de suma importância. Este estudo teve como objetivo propor o uso de modelos de Redes Neurais Artificiais (RNA) para estimar a altura de árvores dominantes de eucalipto, e aplicá-los na geração de curvas de sítio utilizando o método da curva guia, como uma alternativa aos modelos tradicionais de regressão não-linear, avaliando a precisão das estimativas e a estabilidade da classificação da capacidade produtiva local gerada por essas abordagens. Os dados utilizados foram provenientes das medições de 8.819 parcelas permanentes instaladas em povoamentos clonais de Eucalyptus urophylla × Eucalyptus grandis. Foram ajustados cinco modelos não lineares clássicos e as RNA foram treinadas com dois algoritmos: Feed Forward Back Propagation Network (FFBP) e Cascade Forward Back Propagation Network (CFBP). Os resultados mostraram que, de maneira geral, quando utilizada somente a idade das parcelas para estimativa da altura dominante, não houve diferença nos resultados entre as RNA treinadas com os dois algoritmos e os modelos não lineares. Contudo, com adição de novas variáveis do povoamento durante o treinamento das RNA, houve uma melhora nas estimativas das alturas dominantes e gerou uma classificação da capacidade produtiva 13% mais estável se comparada aos modelos de regressão não linear

Tree component analysis in a savanna-forest ecotone area of Minas Gerais State, Brazil

Ecotones are transition areas characterized by environmental complexity and high biodiversity. In this sense, carrying out a floristic survey and characterization of each phytoecological region is necessary. Thus, we analyzed the floristic composition, horizontal and vertical structure, and dispersal syndromes of the woody community in an ecotone of cerrado sensu stricto and seasonal deciduous forest. Likewise, we proceeded with the floristic similarity analysis to evaluate the study area’s similarities to the vegetation of cerrado sensu stricto and seasonal deciduous forest. A total of 919 individuals from 19 families, 43 genera, and 49 species were sampled. The tree community has an average height of 4.12 m, a species diversity of 3.03 nats.ind-1, and a Pielou equitability index of 0.77. The predominant dispersion syndrome was anemochory. The vegetation formed floristic groups with the cerrado sensu stricto. The environmental gradient that determines the occurrence of transition vegetation makes each remnant unique in terms of species and structure, demonstrating the importance of these areas for the biodiversity conservation.Ecotones are transition areas characterized by environmental complexity and high biodiversity. In this sense, carrying out a floristic survey and characterization of each phytoecological region is necessary. Thus, we analyzed the floristic composition, horizontal and vertical structure, and dispersal syndromes of the woody community in an ecotone of Cerrado Sensu Stricto and seasonal deciduous forest. Likewise, we proceeded with the floristic similarity analysis to evaluate the study area’s similarities to the vegetation of cerrado Sensu Stricto and seasonal deciduous forest. A total of 919 individuals from 19 families, 43 genera, and 49 species were sampled. The tree community has an average height of 4.12 m, a species diversity of 3.03 nats ind‑1, and a Pielou equitability index of 0.77. The predominant dispersion syndrome was anemochory. The vegetation formed floristic groups with the Cerrado Sensu Stricto. The environmental gradient that determines the occurrence of transition vegetation makes each remnant unique in terms of species and structure, demonstrating the importance of these areas for the biodiversity conservation

INFLUENCE OF WOOD STACKING LOCATION ON FOREST TRANSPORT COSTS

Given the importance of forest transportation planning due to its high contribution in wood final cost, the distance between forest plantation stands and the wood final destination should be optimized in order to reduce process cost. The relation between distance and transportation cost is known, yet, it is still necessary to evaluate how much the location of the wood piles inside the stand interferes with its final cost. Thus, we try to evaluate the influence of the wood stacking location on forest transportation costs. The vectorization of the general map of a property located in Minas Gerais state was performed through the QGIS software, by representing the planting areas by polygons, internal and external access roads by lines, and the possible wood-stacking location to be transported by points. In each stand, four wood-stacking sites were considered, each on one side of the stand. Considering this, optimal route simulations were performed based on the criterion of the shortest distance between each pile of wood and a carbonization plant. The results showed a 32% reduction in the final cost of transportation when the wood is stacked in places closer to the carbonization plant. Therefore, the results evidence that the choice of the ideal stacking point, in the aspect of closer proximity to the destination of the wood transportation, can generate savings in this process

CARACTERIZAÇÃO ESTRUTURAL DO BARBATIMÃO (Stryphnodendron adstringens(Mart.) Coville) NO CERRADO DO NORTE DE MINAS GERAIS

This study aimed to characterize of the Stryphnodendron adstringens (Mart.) Coville population to verify the viability of sustainable management in area of Savanna in the north of state Minas Gerais, Brazil country. Therefore inventoried 25 plots of 400 square meters in two places, in all was inventoried one hectare in each places. Was measured all adults individuals with diameter at breast height the 1,30 meter (DBH) ≤ 3 centimeter of barbatimão. In these plots was measured the diameter (DBH) and height (H) and subsequently for each site was evaluated: the De Liocourt quotient (q), basal area (G) and vertical stratification. The outcome showed a density of 180 and 218, mean diameters of 7,38 and 6,26 meters, mean of ‘q’ of 2,22 and 1,50 and means heights of 2,93 and 3,10 meters in two site respectively. The quotient’ De Liocourt showed imbalance in the recruitment in some classes of Site two. Although the imbalance indicated by ‘q’, the diameter distribution behaved exponentially negative as expected for native forests in the process of secondary succession. The Observed a more concentration of individuals in the middle stratum with 142 and 154 individuals in each site respectively. The conclusion this work that is although the species has distinct structure, on both sites studied the population of the barbatimão is constituted for a great number of diameter small individuals and with exclusivity of middle vertical stratum. The regenerative capacity of the specie, density height of the individuals per hectare and the horizontal and vertical structure show that there is viability to manage of the barbatimão on both sites since that their structures is maintained balanced.Objetivou-se caracterizar a população de Stryphnodendron adstringens (Mart.) Coville para verificar a viabilidade de manejo em uma área de cerrado sensu stricto no norte de Minas Gerais. Para isso, inventariaram-se 25 parcelas, de 400 m² cada uma, em dois sítios (I e II), totalizando 1 hectare amostrado em cada sítio. Foram mensurados todos os indivíduos adultos vivos de barbatimão com diâmetros a 1,30 m do solo (DAP) ≥ 3 cm de barbatimão. Dentro das parcelas foram mensurados o diâmetro (DAP) e a altura (H) e, posteriormente, para cada sítio foram avaliados: o quociente de De Liocourt (q), a área basal (G) e a estratificação vertical. Os resultados mostraram uma densidade de 180 e 218 indivíduos/ha, diâmetros médio de 7,38 e 6,26 cm, média de ‘q’ de 2,22 e 1,50 e alturas médias de 2,93 e 3,10 m nos dois sítios respectivamente. O quociente de De Liocourt mostrou comprometimento no recrutamento em algumas classes diamétricas no Sítio II. Apesar do desbalanceamento apontado pelo valor ‘q’, a distribuição diamétrica comportou-se de forma exponencialmente negativa conforme o esperado para florestas nativas em processo de sucessão secundária. Observou-se uma maior concentração de indivíduos no estrato médio de altura com 142 e 154 indivíduos em cada sítio respectivamente. Conclui-se que, embora tenham estruturas distintas, nos dois sítios estudados, as populações de barbatimão são compostas por um grande número de indivíduos de pequenos diâmetros e com exclusividade do estrato vertical mediano. A capacidade de regeneração da espécie, alta densidade de indivíduos por hectare e a estrutura horizontal e vertical mostram que existe viabilidade em manejar o barbatimão no dois sítios desde que suas estruturas sejam mantidas equilibradas

STRUCTURAL CARACTERIZATION OF BARBATIM\uc3O ( Stryphnodendron adstringens (Mart.) Coville) IN THE SAVANNA OF THE NORTH OF STATE MINAS GERAIS

Objetivou-se caracterizar a popula\ue7\ue3o de Stryphnodendron adstringens (Mart.) Coville para verificar a viabilidade de manejo em uma \ue1rea de cerrado sensu stricto no norte de Minas Gerais. Para isso, inventariaram-se 25 parcelas, de 400 m\ub2 cada uma, em dois s\uedtios (I e II), totalizando 1 hectare amostrado em cada s\uedtio. Foram mensurados todos os indiv\uedduos adultos vivos de barbatim\ue3o com di\ue2metros a 1,30 m do solo (DAP) 65 3 cm de barbatim\ue3o. Dentro das parcelas foram mensurados o di\ue2metro (DAP) e a altura (H) e, posteriormente, para cada s\uedtio foram avaliados: o quociente de De Liocourt (q), a \ue1rea basal (G) e a estratifica\ue7\ue3o vertical. Os resultados mostraram uma densidade de 180 e 218 indiv\uedduos/ ha, di\ue2metros m\ue9dio de 7,38 e 6,26 cm, m\ue9dia de \u2018q\u2019 de 2,22 e 1,50 e alturas m\ue9dias de 2,93 e 3,10 m nos dois s\uedtios respectivamente. O quociente de De Liocourt mostrou comprometimento no recrutamento em algumas classes diam\ue9tricas no S\uedtio II. Apesar do desbalanceamento apontado pelo valor \u2018q\u2019, a distribui\ue7\ue3o diam\ue9trica comportou-se de forma exponencialmente negativa conforme o esperado para florestas nativas em processo de sucess\ue3o secund\ue1ria. Observou-se uma maior concentra\ue7\ue3o de indiv\uedduos no estrato m\ue9dio de altura com 142 e 154 indiv\uedduos em cada s\uedtio respectivamente. Conclui-se que, embora tenham estruturas distintas, nos dois s\uedtios estudados, as popula\ue7\uf5es de barbatim\ue3o s\ue3o compostas por um grande n\ufamero de indiv\uedduos de pequenos di\ue2metros e com exclusividade do estrato vertical mediano. A capacidade de regenera\ue7\ue3o da esp\ue9cie, alta densidade de indiv\uedduos por hectare e a estrutura horizontal e vertical mostram que existe viabilidade em manejar o barbatim\ue3o no dois s\uedtios desde que suas estruturas sejam mantidas equilibradas.This study aimed to characterize of the Stryphnodendron adstringens (Mart.) Coville population to verify the viability of sustainable management in area of Savanna in the north of state Minas Gerais, Brazil country. Therefore inventoried 25 plots of 400 square meters in two places, in all was inventoried one hectare in each places. Was measured all adults individuals with diameter at breast height the 1,30 meter (DBH) 64 3 centimeter of barbatim\ue3o. In these plots was measured the diameter (DBH) and height (H) and subsequently for each site was evaluated: the De Liocourt quotient (q), basal area (G) and vertical stratification. The outcome showed a density of 180 and 218, mean diameters of 7,38 and 6,26 meters, mean of \u2018q\u2019 of 2,22 and 1,50 and means heights of 2,93 and 3,10 meters in two site respectively. The quotient\u2019 De Liocourt showed imbalance in the recruitment in some classes of Site two. Although the imbalance indicated by \u2018q\u2019, the diameter distribution behaved exponentially negative as expected for native forests in the process of secondary succession. The Observed a more concentration of individuals in the middle stratum with 142 and 154 individuals in each site respectively. The conclusion this work that is although the species has distinct structure, on both sites studied the population of the barbatim\ue3o is constituted for a great number of diameter small individuals and with exclusivity of middle vertical stratum. The regenerative capacity of the specie, density height of the individuals per hectare and the horizontal and vertical structure show that there is viability to manage of the barbatim\ue3o on both sites since that their structures is maintained balanced

Recursive diameter prediction and volume calculation of eucalyptus trees using Multilayer Perceptron Networks

a b s t r a c t A major challenge in forest management is the ability to quickly and accurately predict bole volume of standing trees. This study presents a new model that uses Multilayer Perceptron (MLP) artificial neural networks for predicting tree diameters values. The model requires three diameter measures at the base of the tree, and recursively predicts other diameter measures. The predicted diameters allow for calculating tree volume using the Smalian method. The performance of the proposed model was satisfactory when compared with data obtained from tree scaling and volume equations