César Augusto Guimarães Finger

Efeito do espaçamento e da adubação no crescimento de um clone de Eucalyptus saligna Smith.

In this research, the spacing (3 x 2, 3 x 3 and 3 x 4 m) and fertilization (400 and 800 kg/ha) effects on growth of Eucalyptus saligna clone were studied. The growth in diameter at breast height (Dbh), height (h) and volume per tree were studied from ages between three and ten years, using the Backman’s function. By covariance analysis it was possible to verify that the treatments with the same spacing showed same growth pattern, for all variables. During all observed period, the fertilization treatment had no effect on mostly of the studied characteristics. The factor spacing had outstanding influence in the growth in diameter and commercial volume without bark per tree. Only the trees under the smallest spacing showed a trend of growing slowly in height over time. The volume yield per ha without bark was smaller for the treatments with larger spacing. No differences in volumetric production were found between the two smaller spacings.

O crescimento da Nectandra megapotamica Mez., em floresta nativa na depressão central do Estado do Rio Grande do Sul

This work was carried out with the objective of studying the growth in diameter, commercial volume, form factor, mean annual increment of the commercial volume in percentage for two dominant trees of Nectandra megapotamica, in a Decidual Seasonal Forest, located in the municipal district of Santa Maria in the central depression of the State of Rio Grande do Sul, Brazil. The data were obtained from stem analysis and the growth trend in diameter, commercial volume, form factor and mean annual increment of the commercial volume in percentage, were fitted using the models of Mitscherlich & Sontag (1982), Backman (1943), Richards (1959), and a second degree parabolic model. The adjustment of the models indicated that for the diameter and commercial volume, the best model was that one from Mitscherlich & Sontag, for tree number one and for tree number two, the Richards model presented better adjustment. For the mean annual increment of the commercial volume in percentage, the best model was that one from Backmam, being the parabolic model better for the form factor .

DETERMINAÇÃO INDIRETA DO ESTOQUE DE BIOMASSA E CARBONO EM POVOAMENTOS DE ACÁCIA-NEGRA (Acacia mearnsii De Wild.)

This work was carried out to estimate the carbon storage in even-aged stands of Acacia mearnsii De Wild., in the region of the Southeast Lower Hillside, in Rio Grande do Sul, by the method of derivation of volume and carbon. The biomass components and carbon content were measured in stands 4 to 8-year-old. The method of derivation of volume and carbon was efficient to determine the carbon storage, since the average relative difference was only 4.4%, when considering the whole sample, and independent from stands age. The mean wood basic density found was 0.6 g/cm 3 , regardless of stand age. The mean biomass ratio of the barked-volume to the volume of leaves, branches, litter, and roots was found to be 0.59, independent of stand age. The mean carbon concentration, regardless stand age, was 0.40. The estimated carbon storage by the method of volume and carbon derivation, for 7-year-old stands, was 99.46 t ha -1 , in site index 20; 82.89 t ha -1 , in site index 16; and 46.13 t ha -1 , in site index 12.

Crescimento da acácia-negra, Acacia mearnsii De Wild em diferentes espaçamentos.

In the present work the influence of initial spacing on growth of Acacia mearnsii de Wild was studied. The experiment was conducted in randomized blocks with five treatments and four repetitions defined by spacing between plants of 1 x 1m, 2 x 1m, 3 x 1m, 3 x 1,33 m and 3 x 2 m. The results allowed the conclusion that the smaller the spacing the larger the production of wood with bark on a per hectare basis; however this happenned with Smaller men diameter. The growth of diameter and total height was directly proportional to spacing, but basal area, volume outside bark and weight of the green bark per hectare were inversely proportional to spacing. Dominant height was not affected by the spacings used.

Modelos de crescimento em diâmetro de árvores individuais de Araucaria angustifolia (Bertol.) Kuntze em Floresta Ombrófila Mista

This work aims to model the diameter growth for individual trees of Araucaria angustifolia , present in the Mixed Ombrophylous Forest in the northeast of Rio Grande do Sul. Thus, 251 araucaria individuals located on the permanent plots of the Project PELD – CNPq were remeasured after a period of 8 years. A yield model was built, having as dependent variable the future diameter, using regression and analysis of covariance. As independent variables, the dimensional and social characteristics of the individuals and distance independent competition indices were used. The most correlated variable with the future diameter was the current diameter. The competition indices showed high correlation with the dependent variable, representing the competitive pressure exerted on the tree, but they were not selected in the regression model. Only the current diameter, multiplied by a coefficient, plus a constant value which differed according to the sociological position of the individuals was effective to predict the future diameter. Three variations of the production model were built. The models showed better estimates for emerging individuals of Araucaria angustifolia, however, its use in the individual tree growth prognosis should be cautious due to the magnitude of the errors it presented.

Tamanho de amostra para experimentos de Eucalyptus saligna Smith em viveiro.

The present paper work aimend at determining the sample size for experiments of Eucaliptus saligna SMITH in the tree nursery. The experiment eas established at Barba Negra Forest eserve located in the production area of Riocell S.A in Barra do Ribeiro- RS. To determine the ample size, a total of eight blocks with ninety six seedlings each block were used. The measured ariables were: the plant total height and the diameter of the connecting point of root and stem aeasured by a millimeter graduated pachymeter. It was observed that the results obtained in the nursery show that experimental design must be the block at random, using the tray as a lock. The size of the ideal sample to variable diameter is the with 26 seedlings for each eatment with significant minimum difference of 10% and nine seedlings for each treatment when difference goes to 20%. To the difference goes 20%. It is impossible to delineate an experiment when the difference goes to 5% to both variables.

Modelos de afilamento para o sortimento do fuste de Pinus taeda L

This research had as objective to evaluate different taper models for Pinus taeda and select the best one to estimate variables of interest throughout the stem. The functions proposed by Anony, Kozak, Munro, Silva & Sterba, Prodan and the 5° degree Polynomial were evaluated. With data from rigorous cubage of 68 trees, with 25 years old, coming from plantation of Florestal Gateados Ltda, located, in the city of Campo Belo do Sul, SC, Brazil. Based on the statistics adjusted coefficient of determination (R2aj), standard error of estimates (Syx), bias, average of differences (md) and standard deviation of the differences (dpd) was selected the Polynomial of 5th degree to estimate as the commercial high, commercial volume and the diameters of the 1st and 2nd logs. The commercial heigh results without tendencies with errors oscillating in a small interval, and by the commercial volume a certain tendency of underestimate trees with smaller DAP, and a light tendency for those trees with bigger dap can be observed. Regarding the diameter and volume of the first log an overestimate of the values occurred, but with small errors, mainly for the diameter. For the estimates of the diameter and volume of the second log the results were better than those found for the first log, with light underestimate tendency of the diameter and, practically, without tendency for the volume.

Produção de madeira e casca verde por índice de sítio e espaçamento inicial de acácia-negra, Acacia mearnsii De Wild.

Normal 0 21 MicrosoftInternetExplorer4 No presente trabalho, foram elaboradas tabelas de producao de madeira e casca verde para Acacia mearnsii . Com dados originados de parcelas temporarias e permanentes instaladas em diferentes espacamentos, distribuidas sobre toda a area de plantio desta especie, foram ajustadas equacoes de regressao que apresentaram um coeficiente de determinacao ajustado superior a 0,98 e um baixo erro padrao da estimativa em percentagem. Do estudo, resultaram cinco tabelas de producao por indice de sitio, estratificadas por espacamento inicial que contem o crescimento de altura dominante, diâmetro medio, altura media, area basal, volume com e sem-casca por hectare, peso de casca verde por hectare e incremento medio anual em volume com casca.

Análise da mortalidade de Acacia mearnsii De Wild.

The mortality probability of the Acacia mearnsii De Wild. stands was studied in permanent sample stratified at different spacings and site. The results allowed to conclude that the mortality can estimated with a probabilistic function in relation with the inverse of the diameter at breast height (d) and age (t): PM = {1+ EXP (-9,5593 . d -1 + 104,9543 . t -1 )} –1 . By the Pearson correlation of the mortality rate it was verified a high association with age, average diameter, average height, dominant height, basal area, volume and vital spacing. It was verified that the mortality is directly related to age, site quality and vital spacing in some periods of growth of the trees in the stand.

Competição assimétrica e o incremento diamétrico de árvores individuais de Cedrela odorata L. na Amazônia ocidental

A dependent and independent growth distance model was fitted to evaluate how competition variables may account for the variation of periodic diameter increment of 132 Cedrela odorata trees. Using a Potential Relative Increment (PRI), the relative diameter increment (IRd) was estimated from the multiplication of maximum diameter growth (potential increment) by modified function (portion of the reduced growth due to competition by light and growth space). The significance of the reduced fitted model demonstrated the influence of asymmetric competition variables on diameter growth, explaining 71% of the total variation as well as indicated that competition responses were not constant, but it varied among the different size classes of trees.