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Azadirachta indica (indian neem) is an exotic species that presents high adaptability to different edaphoclimatic conditions, being employed for several uses, mainly wood for energy purposes. use of its wood for energy purposes. In this context, the aim of this research was to evaluate the physicochemical and energetic characteristics of charcoal from wood in two diametric classes: class 1 (8,59 – 10,50 cm) and class 2 (4,78 – 6,07 cm). 10 trees from the indian neem species were randomly sampled (Azadirachta indica), five individuals for each diametric class, with different ages and taken cutting disk to 0 (basis) 25, 50, 75 and 100% from the commercial level, of which the volume of wood with bark, without bark, the percentage volume of bark and dry mass of wood were calculated. Diametrically opposed wedges were used to determine the basic density of the wooden disks. The remaining wedges of the disks were applied for carbonization, evaluation of yields and physical and energetic characteristics of the produced charcoal. The test of Test t of Students (p ≤ 0,05) was employee in the analysis and assessment of the results. Diametric class 1 showed a higher mean basic density (0,57 g cm-3 ) than the mean value of class 2 (0,47 g cm-3 ). Diametric class 2 had the highest levels of bark (20,94%). The charcoal yield was higher in class 1 (35.36%). The Azadirachta indica Showed good potential for the production of charcoal, which could reduce the anthropic pressure on the native species intended for this purpose. [ABSTRACT FROM AUTHOR]

Studies that seek to identify potential techniques for obtaining diameter values at 1.30 m from the ground from tree height data are necessary, especially when considering the use of airborne Lidar in forest inventory activity. In this sense, this work aimed to evaluate two artificial intelligence tools for this purpose, namely the neurofuzzy inference systems and the artificial neural networks. Four models were tested to obtain estimates for the diameter variable, which were prepared by combining the independent variables useful area per plant, age and height. After processing, the statistics of bias, square root of the mean squared error in percentage, correlation and mean percentage error were calculated, in addition to the preparation of scatter plots and histogram of residues. It was observed that, for the estimation of the diameter in both techniques, the use of the model with all independent variables obtained the best values for the analysis statistics. It can be concluded that both tools can be used to estimate the diameter, with the neuro-fuzzy inference system being more suitable for its processing speed and small variability between the values obtained in different training sessions for the same database. [ABSTRACT FROM AUTHOR]

Various edaphoclimatic factors influence mango productivity (dendrometry, flowering and fruiting). The objective of the study was to analyze the edaphoclimatic factors that influence the productivity of 3 mango varieties (Keitt, Ataúlfo and Manila) in the Papaloapan Basin in Veracruz, Mexico. Dendrometric measurements were carried out on trees of 3 mango varieties in 15 orchards (n = 5 orchards per variety) and the values of 33 edaphoclimatic variables were acquired using geographic information systems; a comparison analysis was carried out with the dendrometric and edaphoclimatic variables. The Manila variety stood out in dendrometric terms as a response to ideal edaphoclimatic conditions for its physiological development. However, the 3 varieties are developed under unique edaphoclimatic values to which they are already adapted, with Keitt and Manila having the highest productivity. [ABSTRACT FROM AUTHOR]

The main aim of this research study is to assess the effect of plant spacing on vegetative development and crown morphometry of Bertholletia excelsa Bonpl. (Brazil nut) in the Peruvian Amazon. Two 16-year-old plantations with different initial spacings are examined by measuring the dasometric variables of 474 B. excelsa trees to calculate five morphometric crown indices. The results show that the highest vegetative development is found in trees with the smallest initial spacing. Diameter and height are negatively correlated with slenderness rate and salience index while coverage index and crown shape have a negative correlation with diameter. Tree development and crown morphometry of B. excelsa are significantly affected by initial spacing. In conclusion, plant spacing is an important parameter for establishing and managing B. excelsa plantations in the Peruvian Amazon. [ABSTRACT FROM AUTHOR]

This work, prepared for the special issue of Journal Floresta, aimed to bring together the most significant contributions made by professors and collaborators in the area of Forest Management in the undergraduate and graduate courses in Forestry at the UFPR during the last 50 years. For its elaboration, it was decided by the sectorization of its content in themes, whose sequence included the evolution in the fields of forest mensuration, forest inventory, geotechnologies, statistics, planning and optimization of forest production, biomass and carbon in forests and their products, forest management, and their prospects. The reports clearly showed that during this period there were major evolutions and improvements in the training of forest engineers, as well as masters and doctors in this field of knowledge. The research was developed during this period, not only in the theoretical domain, but also in the technological and operational ground, due to the group's strong interaction with the productive forest sector and with the public institutions of the state of Paraná and the federal government. The training of masters and doctors was expressive, with the highest productivity in the Graduate Program in Forest Engineering at UFPR. In all the topics covered were presented the new directions for the evolution of scientific and technological knowledge in the field of Forest Management. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the adjustment of taper models with and without bark for clone GG100 in a commercial plantation located in the southern state of Tocantins. Twenty-five trees were cubed in which data were fitted five taper models, three of which were the most used in Brazil and two representing the poorly tested models in the country. In the evaluation of the taper models, the following statistical criteria were adopted: standard error of the estimate, adjusted coefficient of determination, mean deviation, sum of squares of the relative residue, percentage residue, and analysis of the distribution of residues. It was concluded by an exponent-shape type model to describe the trunk profile with and without bark of individual clones of clone GG100. [ABSTRACT FROM AUTHOR]

Global warming has become international concern, culminating with the ratification of the Kyoto Protocol which includes definitions and objectives of the sustainable development mechanisms and features that make it easier for the industrialized countries to jointly compensate for their polluting greenhouse gas emissions. São Paulo is a state known for its industrial development and distortion of the green areas in ecosystems associated with the Atlantic Forest biome. In the middle of this chaotic scenery lies the Billings reservoir in São Bernardo do Campo-SP, its forest ecosystem is the provider of numerous environmental services. Quantification of biomass (Bwood) of stems resulted in estimates of 113.73.ha-1, which corresponded to 56.87 tC.ha-1. The estimates obtained for the forest ecosystem of the reservoir can be used as a reference for the establishment of forest restoration projects under the under the sustainable development mechanism established the Kyoto Protocol. [ABSTRACT FROM AUTHOR]

The sustainable agriculture of forest plantations demands the permanent monitoring of the quantity of processed wood, thus becoming difficult to monitor large planted areas by using only manual procedures. Therefore, in this research artificial neural networks (RNA) of multilayer perceptrons, were modeled to estimate the spatial of wood volume in a Eucalyptus-sp plantation located in the state of Mato Grosso del Sur in the Central-West region of Brazil. As input variables in the RNA spectral bands, the textures of the bands obtained with Gray Level Co-occurrence Matrices and vegetation index were used, which were derived from digital satellite image Spot 6. The resulting RNA with the best performance presented accuracy of 93.32% and coefficient of determination of 0.9761. However, this network presented a mean square error of 16.32% (RMSE de 7.85 m³ha-1), but with a unbiased distribution of the residuals. So, the model showed to be suitable to monitor the amount of wood in large areas without overestimating or underestimating the prediction. Compared with different machine learning methods using the same variables, the built network seems to have a higher precision and accuracy. Even in the neuronal models using only spectral bands and vegetation indexes, a better performance was evidenced, showing that the textures contribute in the improvement of predictions. [ABSTRACT FROM AUTHOR]

The aim of this work was to assess the occurrence of Sclerocarya birrea in Chigubo district to provide information about its productive potential to promote the production of canhu oil by local communities. Diameter at breast height (DBH), total height and commercial height and species names were collected in 10 clusters of four plots with 0.2 ha each. The plots were randomly established in the area to determine horizontal forest structure, diameter distribution and timber volumes per unit area. Later on it was estimate de canhu nuts production in Chigubo district. We found diameter distribution in reverse J-shaped, 106 trees ha-1, with 50.59% from S. birrea, and total basal area of adult species of 34.26 m² ha-1, with 24.36 m² ha-1 (71.01%) represented by S. birrea. Sclerocarya birrea nuts production was estimate as 13,345 kg ha-1year-1. [ABSTRACT FROM AUTHOR]

This study aimed to assess the accuracy of different hypsometers: Blume Leiss [BL], Suunto [ST], Relascope [RL], Vertex [VX], Haga [HG] and TruPulse [TP] for height measuring. Data were collected from telescopic poles (A, B and C with 4.45, 10.75 and 7.8 m, respectively) using thirteen different observers. The height was analyzed by analysis of variance in randomized block and tested by Tukey test. The t test (99% significance) was also used to compare equality between real total height of each telescopic pole and heights measured with hypsometers. The results showed that only the RL was different from other hypsometers when all were analyzed together. The hypsometers VX, HG and BL showed the best results in all analyzes, presenting a high semblance to the real height. [ABSTRACT FROM AUTHOR]

The methodologies which are considered the most promising for irrigation management are those based on the analysis of the water status of the plants themselves. This justifies the study and improvement of indicators based on automatic and continuous measures to enable real-time monitoring data, as indices from sap flow, dendrometry and leaf turgor pressure techniques. The aim of this paper is to analyze such methodologies in order to demonstrate their principles, advantages and challenges. In conclusion, the methodologies analyzed still have many technological advances and challenges before being presented to the final user. The future research should work these tools for elaboration of technical indexes that allow their simplification, on the instrumental point of view, and the interpretation of their results. [ABSTRACT FROM AUTHOR]

In this work, from the equation y=bxr, a methodology that links the different geometric solids in four segments of standing trees trunks was developed. Data from 1297 scaled trees of the hybrid Eucalyptus grandis and Eucalyptus urophylla were used for the preliminary analysis and independent data from another 65 scaled trees for the validation of the developed methodology related to the taper and volume predictions. The evaluation criteria of the quality and fitness of the methodology were based on the graphic analyses of the residuals and on the followings statistics: mean percentual deviation, residual standard error, accuracy obtained from the Chi-square test and the variance analyses by the Entirely Randomized Design in Subdivided Blocs with the use of the Dunnett test, both at 0.05 significance level. It was concluded that from a greometric solid, or optimized dendrometric prototype, it is possible to simulated the scaling of standing trees, measuring the trunk diameters located only at: 0.3 m, 1.3 m, h-2/2 and on h-1,25/1,25, besides the total height h, whose processes were included in a methodology named Relative Height Method with Two Diameters (hr2D). [ABSTRACT FROM AUTHOR]

The Mimosa tenuiflora is a species typical of the Brazilian semi-arid region, used as forage, energy source, fences and with potential for production of vegetable tannins. However, there are few studies on the relationships of dendrometric parameters of species. This study aimed to evaluate the volume and mass of wood (firewood) and the volume and mass of bark in Mimosa and verify their variation during the dry and rainy seasons. Thus, were collected, on a quarterly basis, in Santa Terezinha, Paraíba, Brazil, 10 plants of Mimosa tenuiflora, a total of 40 plants, and conducted strict cubic content of wood with and without bark, measurements, determination of moisture content of wood and bark and established relations between the dendrometric parameters. It was noted that the volume and mass of wood are not related to the volume and mass of bark. Moisture content in wood and bark showed that in the months of December 2008 (beginning of the rainy season) and April 2009 (the end of rainy season) was high. In the months of December 2008 and April 2009 higher percentage of green leaves in the trees was observed, due to the occurrence of rain during the collection of the material. [ABSTRACT FROM AUTHOR]

This research aims to analyse the diametric distribution of an Atlantic Forest fragment at Reserva Biológica Sítio Palmares, state of Espírito Santo. In 2,400 m² all trees and palms with DBH over 5 cm were measured. It identified 1364 individuals distributed into 70 species and 33 families. The community population had a DBH average of 14.82 cm and a basal area of 41.12 m².ha-1. For the total population, the DBH distribution into 5 cm intervals formed 13 classes. The adjusted Meyer's equation reveals for this population a tendency to a J-inverse curve. The first three diameter classes from 5 to 20 cm concentrated 79% of the total population. Eight species had a population density with more than 40 trees per hectare. These trees were concentrated until the 40 cm distribution classes. The statistical analysis of the distributions curves reveals that these populations were distributed between the normal, j-inverse and bi-modal curves. [ABSTRACT FROM AUTHOR]

The Sierra Norte of Puebla has commercially potential agroforestry resources but poor planning. The objective was to determine dasometric variables and conditions of the forest land proposing sustainable agroforestry management practices. Systematic sampling was used. The results show a predominance of Quercus sp. and Pinus pseudostrobus. There are combinations of 78 pine trees/ha and 275 oak trees/ha, basal area from 9.30 m²/ha for pine, oak m²/ha 10.67, average height of 18.16 m and 10.07 m, respectively; pine volume is 54.60 m³/ha and 29.04 m³/ha oak. It had three areas: production, restoration and conservation. [ABSTRACT FROM AUTHOR]

This work refers to the classical theory of tree stem form. It shows the derivation of a general sectional volume equation for frustums of solids of revolution generated by the function y2 = pnxn where, pn is a positive constant, and n any positive integer. The cylinder case presents a singular situation because of its sectional volume equation cannot be defined for n = 0 as it is known for the generating function. However, that geometry is implicit as a trivial solution of the derived equation. The known sectional volume equations for frustums of paraboloid, conoid and neiloid are particular cases of that equation for n =1, 2, and 3, respectively. The general sectional volume equation has an unexpected statistical nature. It is given as an arithmetic mean of geometric means The classical theory of tree stem form continue being present in the forest measurement teaching and research. This work could contribute to improve the understanding on that theory. [ABSTRACT FROM AUTHOR]