The effects of contrasting environments on the basic density and mean annual increment of wood from eucalyptus clones

2020 ◽  
Vol 458 ◽  
pp. 117807
Author(s):  
Sarah Esther de Lima Costa ◽  
Rosimeire Cavalcante do Santos ◽  
Graziela Baptista Vidaurre ◽  
Renato Vinícius Oliveira Castro ◽  
Sofia Maria Gonçalves Rocha ◽  
...  
2006 ◽  
Vol 36 (11) ◽  
pp. 2932-2942 ◽  
Author(s):  
Miloš Ivković ◽  
Harry X Wu ◽  
Tony A McRae ◽  
Colin A Matheson

In a companion paper we describe a bioeconomic model of a production system for radiata pine (Pinus radiata D. Don) structural timber and estimated economic weights for four breeding-objective traits: mean annual increment, stem sweep, average branch size, and modulus of elasticity. In this paper we show estimation errors and the sensitivity of the economic weights to the input parameters of the production-system model. We also illustrate the linearity and independence of the economic weights and the sensitivity of selection indices to variation in economic weights and genetic parameters. Estimated standard errors of economic weights were generally low. Among the production-system parameters studied, discount rate and roundwood and sawn-timber prices had the largest impact on the estimates of economic weights. The relationship between the change in values of breeding-objective traits and the corresponding change in profit was nonlinear. The profit change due to change in one objective trait was not independent of the values of the other traits. The most important factors affecting the sensitivity of the selection index were the phenotypic variances of early selection traits such as tree diameter and wood basic density and the economic weights of mean annual increment and modulus of elasticity.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Eliakimu Zahabu ◽  
Tumaini Raphael ◽  
Shabani Athumani Omari Chamshama ◽  
Said Iddi ◽  
Rogers Ernest Malimbwi

This study examined the effects of planting spacing on growth, yield, and wood properties of teak planted at square spacing regimes of 2 m, 3 m, and 4 m at Longuza Forest Plantation, Tanzania. To achieve this, tree, stand, and wood properties were studied at age of 14 years. Results showed that diameter at breast height and total height increased with increasing spacing. Mean annual increment increased significantly with increasing spacing while spacing did not have significant effect on total volume production and basal area. Basic density is also not affected by spacing while heartwood proportion increases as planting spacing increases. All studied wood properties (modulus of rupture, modulus of elasticity, compression strength tangential to grain, and shear tangential to the grain) except cleavage tangential to grain were not significantly affected by increasing spacing. It is recommended to use the spacing of 3 × 3 m, but if thinning can be done before onset of competition at 5 years, the currently used spacing of 2.5 × 2.5 m can still be used. However, the use of a spacing of 4 × 4 m can give at least 50% heartwood at shorter rotation age of 30 years.


Author(s):  
Bruna Isabele Pinheiro da Silva ◽  
Alyne Chaveiro Santos ◽  
Macksuel Fernandes da Silva ◽  
Mariana Dianese Alves de Moraes ◽  
Carlos Roberto Sette Jr

This study aimed to evaluate the energy yield and wood characteristics of Eucalyptus urophylla clones with different mean annual increment of wood volume (MAI). The clones presented MAIs of 39.2, 54.1 and 70.0 m3 ha-1 yr-1 in the field experiment at six years after planting when the trees were cut down to evaluate the wood basic density and higher heating values. The energy density, dry mass and energy yield were estimated. The MAI of E. urophylla clones influenced the wood basic density, dry mass, and energy yield, but did not influence the higher heating value and energy density. Clone 3 had the highest MAI, and also had higher energy yield and dry mass, but lower wood basic density. The difference between the most and the least productive clones was 242,648 MJ ha-1 yr-1. The results reinforce the importance of evaluating the wood quantity production (MAI) to select Eucalyptus clones for energy purposes.


Author(s):  
Пуряев ◽  
Aynur Puryaev ◽  
Мифтахов ◽  
Timur Miftakhov ◽  
Демаков ◽  
...  

The objectives of economic assessment of forests, growing on rich soil and environmental conditions, are especially important for the Republic of Tatarstan, as forest site conditions are presented, mostly, fresh suramens and sudubravas. The aim is to develop an algorithm and a mathematical model of the tax and market value dynamics of stands, needed to justify the choice of target tree species. The object of the study is served as detached electronic database of forestry and forest taxation indices of Kama region, general commodity tables and rate per unit volume of standing wood. The methodology of the study was consistent sort and organize raw data on the studied parameters, as well as the drawing up of mathematical models of the dynamics of the studied parameters. According to the research rezults the algorithm of selecting the target tree species was developed, providing the highest economic benefit in cultivation. The pine stands are most profitable to grow at fresh suramens and oak forests at fresh sudubravas. Age of stand’s economic maturity, which occurs at the climax moment of values of mean annual increment of its tax value, is much lower for most tree species, than the established standard terms of logging.


2020 ◽  
pp. 1-18
Author(s):  
Aliny Aparecida Dos Reis ◽  
Steven E. Franklin ◽  
Fausto Weimar Acerbi Júnior ◽  
Antonio Carlos Ferraz Filho ◽  
José Marcio de Mello

2007 ◽  
Vol 64 (7) ◽  
pp. 1414-1422 ◽  
Author(s):  
Janek Simon

Abstract Simon, J. 2007. Age, growth, and condition of European eel (Anguilla anguilla) from six lakes in the River Havel system (Germany). – ICES Journal of Marine Science, 64: 1414–1422. A total of 199 female yellow European eels (Anguilla anguilla), 21.6–66.2 cm long and 3–14 years old, was collected by electro-fishing from six lakes in the River Havel system (Germany) in spring 2001. The condition and the growth rate, estimated by otolith increments, varied between eels within single lakes and between lakes. Fulton's condition factor ranged from 0.10 to 0.24 and the gross energy content varied between 4.3 and 15.3 MJ kg−1. There were no significant differences in mean condition factor (0.16–0.18) or gross energy content (6.5–9.3 MJ kg−1) between lakes. Fastest growth was in Lake Blankensee (mean 5.3 cm year−1), and the slowest in Lake Sacrow (mean 4.0 cm year−1). For all lakes combined, the overall mean annual increment was estimated to be 4.5 cm year−1. The biggest annual increment on the otoliths was generally laid down during the first and second years in fresh water, when the growth rate was 6.1–8.5 cm year−1. Then, in the subsequent 12 years, the annual increment remained almost constant or decreased slightly (with lake-dependent values of between 1.6 and 6.8 cm year−1). In the River Havel system, the time between stocking of the lakes with glass eels and the recapture of eels at 45 cm body length was 7–10 years. The physiologically possible maximum length (L∞ values) of eels lay in the range 50–130 cm. In comparison with previous investigations (between the 1950s and the 1970s), the only difference observed was a trend towards slower growth.


2003 ◽  
Vol 33 (2) ◽  
pp. 325-329 ◽  
Author(s):  
Kevin T Smith ◽  
Walter C Shortle

Ice storms and resulting injury to tree crowns occur frequently in North America. Reaction of land managers to injury caused by the regional ice storm of January 1998 had the potential to accelerate the harvesting of northern hardwoods due to concern about the future loss of wood production by injured trees. To assess the effect of this storm on radial stem growth, increment cores were collected from northern hardwood trees categorized by crown injury classes. For a total of 347 surviving canopy dominant and subdominant trees, a radial growth index was calculated (mean annual increment for 1998–2000 divided by the mean annual increment for 1995–1997). Sugar maple (Acer saccharum Marsh.), yellow birch (Betula alleghaniensis Britt.), white ash (Fraxinus americana L.), and red maple (Acer rubrum L.) categorized in injury class A (crown loss of less than one-half) had mean growth index values of approximately 1.0, indicating no loss of mean radial growth after 3 years. For injury class B (crown loss of one-half to three-quarters) and class C (crown loss greater than three-quarters), growth index values significantly decreased for sugar maple, yellow birch, and red maple. For white ash, growth index values of classes B and C were not significantly different from those of class A trees. Growth index values of A. saccharum and A. rubrum in injury class C were the lowest of those measured. These results indicated that the severity of growth loss due to crown injury depends on tree species and crown replacement as well as the extent of crown loss.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
José Roberto Soares Scolforo ◽  
Romualdo Maestri ◽  
Antonio Carlos Ferraz Filho ◽  
José Márcio de Mello ◽  
Antônio Donizette de Oliveira ◽  
...  

This study tested the effects of inserting climatic variables inEucalyptus grandisas covariables of a dominant height model, which for site index classification is usually related to age alone. Dominant height values ranging from 1 to 12 years of age located in the Southeast region of Brazil were used, as well as data from 19 automatic meteorological stations from the area. The Chapman-Richards model was chosen to represent dominant height as a function of age. To include the environmental variables a modifier was included in the asymptote of the model. The asymptote was chosen since this parameter is responsible for the maximum value which the dominant height can reach. Of the four environmental variables most responsible for database variation, the two with the highest correlation to the mean annual increment in dominant height (mean monthly precipitation and temperature) were selected to compose the asymptote modifier. Model validation showed a gain in precision of 33% (reduction of the standard error of estimate) when climatic variables were inserted in the model. Possible applications of the method include the estimation of site capacity in regions lacking any planting history, as well as updating forest inventory data based on past climate regimes.


1976 ◽  
Vol 6 (2) ◽  
pp. 132-144 ◽  
Author(s):  
Alan R. Ek ◽  
David H. Dawson

Yields and related stand characteristics of Populus 'Tristis #1' cuttings based on 4 years of growth under intensive culture (fertilization and irrigation) at square spacings of 0.75, 1, and 2 ft (0.23, 0.30 and 0.61 m) in northern Wisconsin are reported. Stem and branch wood yields were 40 390, 45 132, and 27 567 lb/acre (45 272, 50 586, and 30 899 kg/ha) for these spacings, and current annual increment peaked at age 3 for the 0.75- and 1-ft spacings. Tree growth and competition information from these plots was then used to calibrate a stand growth simulation model to develop yield projections to the 10- to 25-year range for the above plus 4-, 8-, and 12.7-ft (1.22-, 2.44-, and 3.87-m) spacings. Mean annual increment in terms of stem and branch wood dry weight for the projections peaked at about 8–15 years for all six spacings with values in the range of 13 881 – 16 584 lb/acre (15 559 – 18 588 kg/ha), respectively. The maximum mean annual increment was obtained at age 15 with a 4-ft spacing. Results further indicate substantial product-oriented flexibility in the choice of spacings and rotation ages since curves of mean annual increment are both similar and relatively flat in the 10- to 20-year range, except for the two widest spacings. A discussion of stand model projection methodology, reliability, and limitations is presented along with suggestions for more refined projections.


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