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The main goal of this study was to evaluate the patterns of diametric increment of open-grown and under competition trees of Pinus taeda L. as an expression of breast height diameter. The dendrometric variables and the diameter increment of these trees were measured. The increments were obtained by measuring tree rings on cores extracted at breast height using a Pressler borer. An allometric model was fitted to describe the percentage periodic annual increment in diameter (PAId%) as a function of the initial diameter (di) for two tree groups. The analysis of covariance (ANCOVA) allowed comparing the effect of intercept (α0) and slope (α1) of the fitted equations between groups. The overall average of PAId5 was 0.83 cm year-1 for open-grown trees and 0.57 cm year-1 for under competition trees. The ANCOVA showed differences in intercept (α0) - (Pr > F = 0.0066) and not in slope (α1) - (Pr > F = 0.8883) for the adjusted regression equations. This finding enabled the development of a singular equation to express the increment, using dummy variables, described as: PAId% = exp [...], with R² = .69 and Syx = 2.4%. The results of this study contribute to highlight the influences of the growth space in the increment of the species, as well as its maximum potential, elements that are very important for the monitoring and decision-making process in silvicultural activities of individual P. taeda trees. [ABSTRACT FROM AUTHOR]

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Copyright of Floresta is the property of Revista Floresta 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 study aimed at modeling competition indices for individual trees of Araucaria angustifolia in natural forests. A total of 397 objective trees were sampled in Lages and São Francisco de Paula municipalities. Through a non-linear regression analysis, 22 distance-independent and distance-dependent competition indices were modeled based on the diameter at breast height (d) and relative height (hrel: ratio between the total height of the objective tree and the maximum potential height estimated for the same diameter). The adjusted equations of the indices according to d of the objective tree achieved values of R2 ≤ 0.546 (Syx% ≥ 15.0). The independent variable hrel improved the estimates, explaining up to 63 % of the variation in the data (Syx% ≥ 14.6). In general, competition indices - which consider in the calculation only the variables d of the objective tree, d of the competitors, its horizontal distance and eventually the height variable- showed superior performance. Therefore, they are indicated for use in growth modeling of A. angustifolia, due to superior facility of application in natural forests. The developed equations showed to be good representations of the degree of competition at the level of the individual tree of A. angustifolia for the two evaluated sites, measuring only the diameter or including the height of the objective tree for more accurate precision. The expansion of research to other sites along the distribution of the species will confirm the application of these equations to their full extent. In addition, this work contributes to the inclusion of competition indices in modeling of individual trees in uneven-aged mixed forests. [ABSTRACT FROM AUTHOR]

Copyright of Floresta is the property of Revista Floresta 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.)

Growth models on level of individual tree are applied for the quantification and description of the factors that affect the growth rate of the trees. The present study aimed to apply the approach of Generalized Linear Models (MLG) to describe the periodic annual increment in basal area of individual trees of Ocotea porosa (Nees) Barroso in natural mixed and uneven-aged forests, considering the measurements of dendometric and morphometric variables, and the competition index. We evaluated three types of modeling of continuous random distributions for a response variable: Normal, Gamma, and Inverse Gaussian; with different link functions: identity (μ), logarithmic (ln μ), and power (μλ). MLG with Gamma distribution and logarithmic link function had the best estimates. The growth of the species was expressed by diameter, total height, crown diameter, h/d relation, and Lorimer competition index. This methodology allowed non-skewed predictions, with greater accuracy, and biological realism in the interpretation of the regression coefficients, when compared to conventional methods of transformation in the dependent variable. [ABSTRACT FROM AUTHOR]

The knowledge and modelling of upper crown exposed to light (UCL) provides relevant informations for forest management of native species, since UCL within the forest is the main photosynthetic area of trees. This study aimed to model the UCL of Cedrela fissilis (Vell.) open-grown trees, using techniques and software for digital design and morphometric analysis. The study included a sample of 53 open-grown trees located in different site conditions. All trees were photographed in two perspectives and analysed with Computer Aided Design (CAD) software for measurement of the dendrometric variables. The analysed data showed trees with diameter at breast height (dbh) between 30-40 and 40-50 cm and UCL mean values of 129.07 and 219.64m2, respectively. The UCL was positively correlated with crown diameter (cd, r = 0.97, P < 0.0001), an index of dbh and tree height (d2h, r = 0.90, P < 0.0001) and with basal area increment (Ig). The proposed methodology was efficient in obtaining morphological data of isolated trees and to analyse data related to the canopy. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop the density management diagram of Araucaria Uneven Aged Forest, located in Lages city, SC. Plots with predominance of Araucaria angustifolia (Bertol.) Kuntze trees growing under high competition were sampled in order to determine the basal area per hectare, the number of trees per hectare, mean basal area diameter, volume per hectare, dominant height and average height, applying the point density method proposed by Spurr (1962). The Reineke (1933) model was adjusted and had recalculated the intercept value to set the maximum density line. The average trading volume in the sample point was estimated with adjustment of Schumacher and Hall (1933) model modified. All models were evaluated for their adjustment statistics, accuracy and graphical analysis of residuals. Slope coefficient of the Reineke (1933) model was -1.5192, confirming the Law of -3/2 power of self-thinning. Management dendrograms developed for basal area, commercial volume in function of the number of trees per hectare and average diameter of basal area, can assist in forest operations, optimizing production according to the condition of the site and growth characteristics of the species. [ABSTRACT FROM AUTHOR]

The present study aimed to develop a mathematical model to describe annual periodic percentage increment in basal area of Araucaria angustifolia trees with data collected from increment cores extracted radially from the trunk at breast height of 109 trees distributed in a large diameter range. Dendrometric and morphometric attributes were tested by multiple linear regressions as independent variables and their interactions with dummy variables as descriptors of social position class. The model explains 80% of total variation of the periodic annual percentage increment in basal area with formal crown and height/diameter relationship for trees of all social positions, as well as length and crown proportion of dominant trees described by the dummy variable. Morphometric variables, especially those that characterize the crown size, are indicated for development of individual tree growth models of Araucaria angustifolia. [ABSTRACT FROM AUTHOR]

Functions describing stem shape allow to determine dimension and volume class, with direct application in technical and economic activities in the forest. The aim of this study was to evaluate the accuracy of the Trapezoidal and Simpson 1/3 rules in the approximation of numerical integration applied to Kozak, Lee et al. and Sharma and Zhang models. The evaluated data were diameter and height of sixty Araucaria angustifolia (Bertol.) Kuntze individuals from a planted forest located in Caçador, State of Santa Catarina, Brazil. Analysis of results showed the high efficiency of the two volume and assortments determination methods compared to the exact value of the numerical integration. Kozak and Lee et al. models showed better results compared to Sharma and Zhang models. The first, when estimating volume of trunk with bark, applying the Trapezoidal rule, showed an error smaller than 10-4, through eight integration intervals, equidistant between sections with relative length equal to 20% of the total height. The Simpson 1/3 rule resulted in greater accuracy with an error smaller than 10-6, though with complex mathematical structure using six equidistant integration intervals. [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.)

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 aim of this study was to evaluate precision and accuracy in estimating horizontal projection crown area of trees of Araucaria Angustifolia in different social positions. We sampled 294 trees in the forest and classified them according to their position in sociological position as dominant, codominant and dominated. In each tree it was measured the diameter at breast height, total height and eight crown radius following the cardinal points direction. The horizontal projection area of the crown was calculated by the average of the respective radius numbers evaluated in the crown (methods): eight, four and two. Statistical differences between among methods were verified by variance analysis with factorial arrangement, considering two factors, methods of crown area and the social position occupied by trees. The results indicated that although there was no significant difference between the mean area of crown projection when measured eight and four radius, the graphical analysis revealed tendency to overestimate the area calculated with four and two radius in irregular crown, often identified in codominant and dominated trees. Furthermore, in relation to symmetrical crowns, determining the area of horizontal projection crown with four radius can be used without loss of accuracy. [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.)

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.)

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 presents a simulation of the regulation of Araucaria angustifolia (Bertol.) Kuntze timber stocks using Liocourt's law. Although this species is currently protected by law, recent government initiatives are being considered to propose sustainable forest management practices by selecting small rural properties in Southern Brazil. Here, we simulate the applicability of Liocourt's law in a typical rural property, the size of which is approximately 85 ha. Forest inventory measurements were conducted by estimating the diameter at the breast height (d), total height (h), and annual diameter increments of 308 trees that fit the criteria of d ≥ 10 cm, distributed on 35 permanent plots of 400 m2 each. As a result, a reverse J-shaped d distribution was found. On average, 303 trees can be found per hectare (ha). Local allometric equations showed their basal area (G) to be 21.9 m2∙ha−1, and their commercial volume (V) to be 172 m3∙ha−1, whereas Liocourt's quotient (q) was 1.31. Based on these attributes, nine different forest management scenarios were proposed by simulating a remaining basal area (Grem) of 10.0, 14.0, and 18.0 m2∙ha−1, and Liocourt's quotient was changed to 1.1, 1.3, and 1.5. All scenarios consider a d of 62.5 cm. In the less intensive scenario (i.e., q value = 1.5 and larger basal area of 18.0 m2·ha−1) there is greater optimization of space, and higher economic return is ensured to rural producers due to the definition of shorter cutting cycles. This also allows a faster growth rate in both d and h for smaller trees, due to the higher incidence of light onto the lower canopy layer, increasing the natural regeneration implementation of other native species. Forest management should thus be considered a goal in addition to consumer market characteristics for defining the ideal timber stock scenario. [ABSTRACT FROM AUTHOR]