scholarly journals Effect of spacing on volume, form factor and taper for Pinus taeda trees in Paraná, Brazil

2021 ◽  
Vol 8 (3) ◽  
pp. 1557-1666
Author(s):  
Guilherme Maia dos Santos ◽  
Ximena Mendes de Oliveira ◽  
Isabel Homczinski ◽  
Rafaella Carvalho Mayrinck ◽  
Willian Dos Santos Cavassim

Several forestry procedures affect tree volume and shape, such as spacing, pruning, and thinning. Studying and understanding the effect of these operations on stand attributes are very important for forest management. This study aimed to evaluate volume, form factor, and taper for Pinus taeda trees stratified into diameter classes within two planting spacings. In addition, we aimed to evaluate the time spent to scale each tree, measured with a chronometer. Indirect scaling was performed using a Criterion RD 1000. Thirty trees were scaled on each planting spacing (3 m x 2 m and 4 m x 2 m), totaling 60 trees encompassing all diameter classes. Tree volume was calculated using the Smalian equation. Tree volume, form factor, and taper were calculated to each tree and evaluated by stand (independent t-test) and diameter class (variance analysis and Tukey test).  The average scaling time was 4 minutes and 35 seconds, which decreased with practice (-24%). Form factor and taper differed with spacing and diameter class. Volume did not differ with spacing, but it did in the diameter classes. We concluded that indirect scaling is a practical method for tree volume assessment; higher planting density leads to more cylindrical stems with lower taper ratios in comparison with denser stands; and the fact that tree volume, form factor and taper differed among the diameter classes should be incorporated into studies of taper modeling.

1992 ◽  
Vol 22 (10) ◽  
pp. 1562-1567 ◽  
Author(s):  
Fernand Pagé ◽  
Bady Badibanga ◽  
Annie Sauvesty ◽  
Colette Ansseau

A method for rapidly estimating the rootlet volume and mass in sugar maple groves was developed in relation with the rootlet size. Soil samples were obtained with corers and cut in 2-cm thick slices. The number of rootlets of diameter classes <0.3, 0.3–0.5, 0.5–0.8, and 0.8–1.0 mm were determined under microscope (× 150) on the upper surface of slices. Rootlet surface for each class was measured on thin sections of soil, with an optic microscope connected to a digitalizing board. Mean rootlet surface [Formula: see text] showed a small standard deviation within each diameter class. The rootlet surface (S) on a surface of soil St can be estimated as [Formula: see text], where N is the number of rootlets observed in nc fields of observation, each field having a surface So. If two soil slices are located at depths h1 and h2, respectively, and if the rootlet surfaces of those slices are S1 and S2, the rootlet volume V of the first slice corresponds approximately to the volume of a truncated cone, and can be calculated as V = [S1 + S2 + (S1S2)0,5] (h2–h1)/3. The rootlet density (g•cm−3 of root) was also determined for each diameter class. The standard deviation from [Formula: see text], the mean density for each diameter class was small. Thus, the rootlet mass M was determined as [Formula: see text]. Estimated and real rootlet volume and mass values were compared. A difference of about 10% was found between estimated and real values.


2005 ◽  
Vol 29 (1) ◽  
pp. 16-21 ◽  
Author(s):  
Ching-Hsun Huang ◽  
Gary D. Kronrad ◽  
Jason D. Morton

Abstract Economic analyses were conducted to investigate the effects of initial planting density on the profitability of loblolly pine (Pinus taeda L.) on nonindustrial private forestland (NIPF) in East Texas. Five planting densities of 870, 725, 620, 540, and 484 trees per acre (tpa)representing spacings of 5×10, 6×10, 7×10, 8×10, and 9×10 ft, respectively, were investigated. Land expectation values were used to determine the financially optimal thinning and final harvesting schedules (including rotation length and the timing, frequency, and intensity of thinning). Five site indices (50–90), six real alternative rates of return (ARR) (2.5–15.0%), and three thinning options (0, 1, and 2) were employed. Results indicate that two thinnings appear to be the financially optimal number of thinnings for most siteindex-ARR scenarios. The planting spacing of 8×10 ft is optimal when ARR is low, and the 9×10 ft spacing is optimal when ARR is high. South. J. Appl. For. South. J. Appl. For. 29(1):16–21.


CERNE ◽  
2010 ◽  
Vol 16 (1) ◽  
pp. 94-104 ◽  
Author(s):  
Eder Pereira Miguel ◽  
Sebastião do Amaral Machado ◽  
Afonso Figueiredo Filho ◽  
Julio Eduardo Arce

This study aimed to fit the Weibull probability density function to stand data so as to represent the distribution of number of trees by diameter class, and also to fit models representing stand attributes so as to project growth and yield by diameter class and also yield of multiple wood products at the relevant rotation age (7 years). Data were collected from Eucalyptus urophylla stands owned by Anglo Americana plc (CODEMIM), a company situated in the municipality of Niquelândia, Goiás state. Initially a 3P-Weibull probability function was fitted by the percentile method for the aggregate stand. Then models were fitted and selected of stand attributes using residuals plot, residual standard error (s yx) and coefficient of determination (R²) as selection criteria. The hypsometric model of Trorey was then used to derive the average height of possible diameter classes, and the taper model of degree 5 and volumetric model of Takata were used to check compatibility of generated volumes. Prognosticated results were consistent with local productivity when compared to previous inventories complied by the same company of stands within the same age group.


2002 ◽  
Vol 18 (2) ◽  
pp. 215-230 ◽  
Author(s):  
Shin-Ichiro Aiba ◽  
Kanehiro Kitayama

We examined the effects of the 1997–98 El Niño drought on nine rain forests of Mount Kinabalu, Borneo, at four altitudes (700, 1700, 2700 and 3100 m) on contrasting geological substrata (ultrabasic versus non-ultrabasic). Measurements of rainfall and atmospheric aridity indicated that the departure from normal conditions during the drought became greater with increasing altitude. During 1997–99 (drought period) compared to 1995–97 (pre-drought period), median growth rates of stem diameter of trees decreased for both smaller (4.8–10 cm) and larger (≥ 10 cm) diameter classes in the six upland forests (≥ 2700 m on ultrabasic substrata and ≥ 1700 m on non-ultrabasic substrata), but for neither diameter class in the other forests. The majority of species decreased or did not change growth rates during 1997–99, whereas some did increase. Tree mortality increased during 1997–99, at the larger diameter class in the two lowland forests (700 m) on both substrata, and at least at the smaller diameter class in the four upland forests (≥ 1700 m) on non-ultrabasic substrata. In two of these upland forests, mortality was restricted to particular understorey species. Mortality did not significantly increase in the three upland forests (≥ 1700 m) on ultrabasic substrata; this suggests that the adaptation to nutrient-poor soils might have provided the resistance to drought.


1986 ◽  
Vol 16 (3) ◽  
pp. 521-528 ◽  
Author(s):  
Dale S. Solomon ◽  
Richard A. Hosmer ◽  
Homer T. Hayslett Jr.

Matrices are used to model ingrowth, survivor growth, and mortality for stands in different forest types in the Northeast. Equations are developed for several species from softwood and northern hardwood stand data estimating the probability of trees remaining in a diameter class, increasing one or two diameter classes, or dying. By knowing species composition and diameter distribution, FIBER predicts stand yields for managed and unmanaged stands with densities ranging from 9.2 to 41.3 m2/ha using 5-year iterations. Actual and predicted volume estimates from independent data sets are compared for different species compositions, densities, thinning operations, and harvest intervals in the softwood, northern hardwood, and mixed-wood forest types.


Author(s):  
Maman Kamal Abdou Habou ◽  
Habou Rabiou ◽  
Laouali Abdou ◽  
Boubacar Moussa Mamoudou ◽  
Ismaël Bio Yandou` ◽  
...  

Balanites aegyptiaca (L.) Del. is a fruit species from the Sahelian and Sudano-sahelian zones, highly appreciated by the population. It provides a source of income for the rural population and its various parts are used for human and animal food, handicrafts and traditional medicine. However, the lack of data on propagation techniques of the species is a significant limitation to its domestication. This study aims to evaluate the vegetative propagation capacity of Balanites aegyptiaca by air layering. The trials were conducted in the Arboretum of Sahara Sahel Foods in Zinder, Niger. The layers were placed on orthotropic branches. The variables selected were the diameter class (1-2 cm, 2-3 cm and 3-4 cm) and the substrates (sand+manure, sand+sawdust and sand). A total of 116 layers were made. The results show that 93.1% of the layers have taken root two months after realization. The diameter classes and the three substrates have no significant influence on the number of roots. In contrast, root length varied significantly with substrates (P = 0.000) and branch diameter classes (P = 0.031). As for the diameter of the newly formed roots, a significant difference was observed between the diameter classes and the substrates have no significant effect on this parameter. One month after weaning of layers, an average survival rate of 68.5% was obtained. The seedlings of the diameter class 2-3 cm have the highest survival rate (83.1%). These results suggest that it is possible to produce Balanites aegyptiaca plants by air layering, and could contribute to the development of strategies adapted to its domestication.


FLORESTA ◽  
2014 ◽  
Vol 44 (4) ◽  
pp. 709
Author(s):  
Cícero Ramos Pereira da Silva ◽  
João Vicente Figueiredo Latorraca ◽  
Jair Figueiredo Carmo ◽  
Pastor Amador Mojena

AbstractThe objective of this study was to determine and evaluate the yield of four (4) diameter classes in function of quality of logs, in logwood processing of Cedrinho (Erisma uncinatumWarm.). 20 logs of four diameter classes between 46 and 85 cm were selected and classified in terms of quality, being 5 logs for each diameter class. Diameter class I resulted in the lowest yield and diameter class III showed the highest yield. Yield increased according to the diameter of the logs in classes I, II and III. Class IV logs with larger diameters had quality defects such as cracks and internal flaws, causing a small yield drop. It could be concluded that there was a correlation between diameter and yield.Keywords: Mato Grosso; sawmill; native wood; correlation. ResumoRendimento de madeira serrada em função de classes diamétricas e padrões de qualidade da tora. O objetivo deste trabalho foi determinar e avaliar o rendimento em diferentes classes diamétricas em função da qualidade das toras no desdobro do Cedrinho (Erisma uncinatum Warm.). Foram selecionadas e classificadas quanto à qualidade 20 toras em quatro classes diamétricas, entre 46 e 85 cm, sendo cinco toras para cada classe diamétrica. A classe diamétrica I apresentou o menor rendimento e a classe diamétricaIII apresentou o maior. O rendimento aumentou de acordo com o diâmetro das toras na classe I, II e III. As toras da classe IV, com maiores diâmetros, apresentaram baixa qualidade, com defeitos como rachaduras e falhas internas, causando uma pequena queda no rendimento. Pode-se dizer que existe uma correlação entre diâmetro e rendimento. Palavras-chave: Mato Grosso; serraria; madeira nativa; correlação.


1988 ◽  
Vol 2 (2) ◽  
pp. 191-195 ◽  
Author(s):  
Robert J. Mitchell ◽  
Bruce R. Zutter ◽  
David B. South

Third-year heights, third-year root-collar diameters, and 3 yr volume growth of loblolly pine seedlings were examined in relation to a) root-collar diameter class at time of planting and b) herbaceous weed control. Treatments were a) no weed control and b) complete control for 2 yr. For both weed control treatments, means for third-year heights, groundline diameters, and volume growth were related positively to initial seedling diameter. The influence of initial seedling diameter on third-year diameters and heights did not differ among weed control treatments. However, the influence of initial diameter on volume growth did differ among weed control treatments. Thus, when using herbaceous weed control, additional gains in early volume growth can be realized by planting seedlings with large root-collar diameters.


Nativa ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 445
Author(s):  
Samuel Nahon da Costa ◽  
Fernando Galvão Rabelo ◽  
Robson Borges de Lima ◽  
Diego Armando Silva da Silva ◽  
Cleyton Wilson Pereira de Lima ◽  
...  

O objetivo desse trabalho foi analisar a estrutura diamétrica e espacial das espécies Manilkara huberi (Ducke) A. Chev. e Dinizia excelsa Ducke. A distribuição diamétrica foi determinada conforme a metodologia de Sturges. O modelo de Meyer foi ajustado para estimar o número de indivíduos por classe de diâmetro. O padrão de distribuição espacial foi estimado por meio do índice de Morisita. Foram encontrados 1.372 indivíduos de M. huberi, onde os dados de sua estrutura diamétrica foram divididas em 11 classes com intervalo de 6,58 cm. Em relação à espécie D. excelsa, foram encontrados 100 indivíduos e seus dados geraram 7 classes diamétricas com 12 cm de intervalo. A distribuição diamétrica dos indivíduos de M. huberi seguiu a distribuição em “J-invertido”, que é típica das florestas naturais inequiâneas, com um quociente “q” estimado de 1,39. Já os indivíduos da espécie D. excelsa apresentaram-se desbalanceados em todos os centros de classes, não seguindo a tendência de “J-invertido”, e um quociente “q” estimado de 1,22. Quanto à distribuição espacial, observou-se por meio do índice de Morisita que ambas as espécies seguem uma distribuição agrupada em que os indivíduos localizam-se próxima à planta mãe, portanto, as populações tendem a ser agrupadas. As espécies possuem distribuição espacial agregado, subsidiando a exploração das árvores com aptidão ao manejo, observando possíveis ressalvas para a espécie M. huberi.Palavras-chave: quociente De Liocourt; índice de Morisita; floresta ombrófila. POPULATION STRUCTURE OF Manilkara huberi (Ducke) A. Chev. AND Dinizia excelsa Ducke IN AN UPLAND FOREST IN AMAPA ABSTRACT: The aim of this work was to analyze the diametric and spatial structure of the Manilkara huberi (Ducke) A. Chev. and Dinizia excelsa Ducke species. The diameters distribution was determined according to the Sturges methodology. The Meyer model was adjusted to estimate the number of individuals per diameter class. The spatial distribution pattern was estimated using the Morisita index. We found 1,372 individuals of M. huberi, where the data of their diametric structure were divided into 11 classes with an interval of 6.58 cm. In relation to specie D. excelsa, we found 100 individuals and their data generated 7 diameter classes with 12 cm interval. The diameter distribution of M. huberi individuals followed the J-inverted distribution, which is typical of uneven-aged natural forest, with an estimated "q" quotient of 1.39. On the other hand, the individuals of the D. excelsa species showed unbalanced in all class centers, not following the J-inverted distribution and estimated “q” quotient of 1.22. As for the spatial distribution, it was observed through the Morisita index that both species follow a grouped distribution in which the individuals are located close to the mother plant, therefore, the populations tend to be grouped. The species have an aggregate spatial distribution, subsidizing the exploitation of trees with aptitude for management, observing possible caveats for M. huberi specie.Keywords: De Liocourt quotient; Morisita index; ombrophylous forest.


2019 ◽  
Vol 13 ◽  
pp. 46
Author(s):  
André Salgado De Andrade Sandim ◽  
Ariadna Coelho Mota ◽  
Mario Lima Dos Santos ◽  
Welton Dos Santos Barros ◽  
Beatriz Cordeiro Costa ◽  
...  

Post-harvest, wood volume can be calculated with a stacking factor which can be influenced by diameter classes involved. Consequently, the following question arises: there is a difference between the volume conversion factor for stacked to geometric volume between piles of clonal plantation logs of different diameters classes? The hypothesis is: if smaller logs have a higher stacked to geometric volume conversion factor, between-log voids will be smaller and the overall stacks will therefore have lower volumes. Therefore, the objective of this study was to compare stacking and cubing factors in stacks of logs with different diameters for two Eucalyptus sp. clones. The study was conducted in Barra do Corda municipality, Maranhão State, Brazil. Timber was laid in piles of logs by diameter class, composed of logs of smaller (9-10.99 cm) and larger (11-13 cm) diameters. Stacking factor means for clone 1 were 1.88 for the larger diameter and 2.00 for the smaller diameter class, while for clone 2 mean values were 1.62 and 1.65, for stacks with larger and smaller diameter classes, respectively. For logs from the same clone there was no significant difference for the conversion factors between the stacks with the largest and smallest diameter. However, there was a significant difference in the conversion factors between the two clones, proving the hypothesis tested. Thus, for each genetic lineage, a proper stacking factor must be established so that the estimated volume comes close to the real value.


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