Dissertations / Theses: 'Radiata pine'

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Welsh, Shayne. "Hormonal control of wood formation in radiata pine." Thesis, University of Canterbury. Biological Sciences, 2006. http://hdl.handle.net/10092/968.

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Pinus radiata is by far the dominant species grown in New Zealand plantations as a renewable source of wood. Several wood quality issues have been identified in the material produced, including the high incidence of compression wood, which is undesirable for end users. At present our understanding of the complex array of developmental processes involved in wood formation (which has a direct bearing on wood quality) is limited. Hence, the forest industry is interested in attaining a better understanding of the processes involved. Towards this goal, and for reasons of biological curiosity, the experiments described in this thesis were carried out to investigate several aspects of xylem cell development. In an in arbor study, changes in the orientation of cortical microtubules and cellulose microfibrils were observed in developing tracheids. Results obtained provide evidence that cortical microtubules act to guide cellulose synthase complexes during secondary wall formation in tracheids. The mechanisms involved in controlling cell wall deposition in wood cells are poorly understood, and are difficult to study, especially in arbor. A major part of this thesis involved the development of an in vitro method for culturing radiata pine wood in which hormone levels, nutrients, sugars and other factors, could be controlled without confounding influences from other parts of the tree. The method developed was used in subsequent parts of this thesis to study compression wood development, and the influence of the hormone gibberellin on cellulose microfibril organisation in the cell wall. Results from the in vitro compression wood experiments suggested that: 1. when a tree is growing at a lean, the developing cell wall was able to perceive compressive forces generated by the weight of the rest of the tree, rather than perceive the lean per se. 2. ethylene, rather than auxin, was involved in the induction of compression wood. Culture of stem explants with gibberellin resulted in wider cells, with steeper cortical microtubules, and correspondingly steeper cellulose microfibrils in the S2 layer of developing wood cells. This observation provides further evidence that the orientation of microtubules guides the orientation of cellulose microfibrils. Overall, the work described in this thesis furthers our knowledge in the field of xylem cell development. The stem culture protocol developed will undoubtedly provide a valuable tool for future studies to be carried out.

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Hsu, Ching Yi. "Radiata pine wood anatomy structure and biophysical properties." Thesis, University of Canterbury. Forestry, 2003. http://hdl.handle.net/10092/7202.

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Several important characteristics such as density, acoustic velocity, modulus of elasticity and tracheid dimensions are examined in stemwood, branchwood and rootwood in young (age 3 and 7) Pinus radiata. Stemwood air-dry density decreases little from ground level to the top of the tree falling gradually from 415 kg/m³ to 405 kg/m³. Branchwood air-dry density is higher than stemwood density. The branchwood density is approximately 480 kg/m³ close to the stem and then decreases sharply to ca. 410 kg/m³ near the branch tips. Rootwood density at 12% moisture content is similar to stemwood density ranging between 420 and 405 kg/m³. Density varies from stemroot junction to root tip in lateral roots (420 to 405 kg/m³) but changes little along tap roots (405 kg/m³) In stemwood, the air-dry modulus of elasticity increases from ground level (ca. 2.5-3.5 GPa) to approximately 4 metres (ca. 5.5-6.5 GPa) and then decreases thereafter to 7 metres (ca. 2.5-3.5 GPa). The air-dry MOE of branchwood decreases linearly with tree height up the stem from approximately 4.5 GPa at 1 metre to 3 GPa at 6 metres. Roots are the least stiff part of the tree. The air-dry MOE value decreases along roots from the stem-root junction (ca. 1.9 GPa) to the root tip area (0.5 GPa) in lateral roots, and from 1.4 GPa to 0.4 GPa in tap roots. In stemwood and rootwood the tracheid dimensions change with distance from ground level in both directions with significant different patterns. For stemwood, the tracheid length decreases with height up the stem. The mean tracheid length is approximately 1.70 mm at breast height whereas it is 1.55 mm and 1.40 mm at 2.4 metres and 4.6 metres respectively. Rootwood tracheids are much longer (nearly double) than stemwood tracheids. The tracheid length increases with increasing distances from the stem-root junction. The mean tracheid length adjacent to the stemroot junction area is approximately 2.2 mm whereas for the middle and root tip areas it is 2.6 mm and 3.3 mm respectively. Compression wood is a common feature of stem and branchwood. However, this atypical tissue is absent in roots except in some restricted instances where compression wood extends a short distance from the stem down into the root. Branchwood in green condition can be used to predict volume-weighted stemwood qualities at 12% moisture content when specific conditions are applied (select a straight portion of first branch segment from the largest diameter branch at breast height, R2 = 0.64). However, this approach has little practical appeal as equally good or better correlations can be obtained using Fakopp on standing trees (R2 = 0.75). Therefore future work should focus solely on the use of time of flight instruments such as Fakopp on stemwood.

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Bloomberg, Mark. "Modelling germination and early seedling growth of radiata pine." Lincoln University, 2008. http://hdl.handle.net/10182/681.

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Background: This study seeks to model aspects of the regeneration of radiata pine (Pinus radiata D.Don) seedlings under a range of environmental conditions. This study investigated whether “hybrid” mechanistic models, which predict plant growth and development using empirical representations of plant physiological responses to the environment, could provide a realistic alternative to conventional empirical regeneration models. Objectives: The objectives of this study were to 1) identify the functional relationships between the environmental conditions controlling germination, establishment and growth of radiata pine seedlings, under a range of those environmental conditions as specified by temperature and available light and soil water; and 2) specify those functional relationships in hybrid mechanistic (“hybrid”) models. Methods: Radiata pine seedling germination and growth were measured under controlled environmental conditions (incubators for seed germination, growth cabinets for seedlings), and results used to adapt, parameterise and test two published hybrid models; one for germination (the hydrothermal time model); and one for seedling growth in the first six months after germination, based on plant radiation use efficiency (RUE). The hydrothermal model was tested by incubating commercial radiata pine seeds under factorial combinations of temperature and water potentials where germination was likely to occur (12.5 ºC to 32.5 ºC and 0 MPa to –1.2 MPa.). 100 seeds were germinated for each factorial combination. The hydrothermal germination model was fitted to the germination data using non-linear regression modles, will allowed simultaneous estimation of all modle parameters. Seedlings were grown in controlled growth cabinets, and their RUE was calculated as the ratio of net primary production (NPP, specified in terms of an increase in oven dry biomass), to PAR intercepted or absorbed by a seedling. Estimation of seedling RUE required development of novel techniques for non-destructive estimation of seedling oven dry weight, and measurement of PAR interception by seedlings. The effect of varying PAR flux density on RUE was tested by measuring RUE of seedlings grown at 125, 250 and 500 µmol m⁻² s⁻¹. In a second experiment, the effect of deficits in available soil water on RUE was tested by measuring RUE of seedlings grown under 250 µmol m⁻² s⁻¹ PAR flux, and at different levels of available soil water. Available soil water was specified by a soil moisture modifier factor (ƒθ) which ranges between 1 for moist soils and 0 for soils where there is insufficient water for seedling growth. This soil moisture modifier had not previously been applied in studies of tree seedling growth. Temperatures for both seedling experiments were a constant 17.5 ºC (day) and 12.5 ºC (night). Results: Hydrothermal time models accurately described radiata pine seed germination. Model predictions were closely correlated with actual seed germination over the full range of temperature and water potentials where germination was likely to occur (12.5 ºC to 32.5 ºC and 0 MPa to –1.2 MPa. The minimum temperature for germination (base temperature) was 9.0 ºC. Optimum temperatures for germination ranged from ~20ºC for slow-germinating seeds to ~27 ºC for the fastest germinating seeds. The minimum water potential for seed germination varied within the seed population, with an approximately normal distribution (base water potential = –1.38 MPa, standard deviation of 0.48 MPa). In the process of developing the model, a novel explanation for the decline in germination rates at supra-optimal temperatures was developed (Section 3.4.6), based on earlier models proposed by Alvarado & Bradford (2002) and Rowse & Finch-Savage (2003). This explanation was that the decline in germination rate was not driven just by temperature, but by accumulated hydrothermal time above the base temperature for germination (T₀). This in turn raised the base soil water potential (Ψb) towards 0, so that the reduction in germination rate arose from a reduced accumulation of hydro-time, rather than from thermal denaturation of enzymes facilitating germination – the conventional explanation for non-linear accumulation of thermal time at supra-optimal temperatures for plant development. Upwards adjustment (towards 0 MPa) of base water potentials of germinating seeds occurred also at very cold temperatures in combination with high water potentials. In both cases (very cold or else supra-optimal temperatures) this upwards adjustment in base water potentials prevented germination of part of the seed population, and is proposed as a mechanism which enables seed populations to “hedge their bets” when germinating under less than ideal germination conditions. RUE of young germinated radiata pine seedlings growing in a controlled growth cabinet was not significantly different over a range of constant PAR flux densities. Mean RUE’s were 3.22, 2.82 and 2.58 g MJ⁻¹ at 125, 250 and 500 µmol m⁻² s⁻¹ respectively. In the second experiment, the novel use of a soil moisture modifier (ƒθ) to predict RUE of seedlings subjected to water stress proved successful within a limited range of soil water stress conditions. Measured seedling transpiration and stomatal conductance were closely correlated but seedling photosynthesis was less correlated with available soil water. This result suggests that photosynthesis was not coupled with stomatal conductance when PAR flux was 250 µmol m⁻² s⁻¹, which is well below saturating irradiance for C₃ plants. Conclusions: The use of hybrid, quasi-mechanistic models to describe tree seedling growth has been seldom explored, which necessitated the development of novel experimental and analytical techniques for this study. These included a predictive model of germination decline at sub- and supra-optimal temperatures; a method for accurately estimating seedling dry weights under a range of PAR flux densities; and a novel method for estimating light interception by small seedlings. The work reported in this thesis showed that existing hybrid models (the hydrothermal time germination model and the RUE model) can be adapted to model germination and growth of radiata pine seedlings under controlled environmental conditions. Nonetheless, further research is needed before the models can be confidently used as an alternative to conventional empirical models to model regeneration in “real-world” forests. Research priorities are the performance of hydrothermal germination models under variable field conditions, and the use of the soil moisture modifier for seedlings growing on a range of soil textures and under a range of PAR fluxes.

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Zou, Chris Bocai. "Soil physical properties and root growth of radiata pine." Thesis, University of Canterbury. Forestry, 1999. http://hdl.handle.net/10092/7493.

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Soil water potential decreased exponentially and soil strength increased logarithmically as the volumetric water content decreased in soils of contrasting texture at a range of bulk densities. Soil air-filled porosity was a linear function of volumetric water content. At constant soil strength and non-limiting soil air-filled porosity (≥ 0.16 cm³ cm-³ the root elongation rate of radiata pine seedlings decreased linearly with soil water potential in the range - 0.01 to - 0.20 MPa. The rate of decrease in elongation rate was reduced with increasing soil strength. When soil water potential was < - 0.20 MPa, the root elongation rate was linearly related to the log of negative soil water potential. The root elongation rate decreased exponentially with increase of soil strength at constant soil matric potential and non-limiting air-filled porosity. This relationship was independent of both soil water potential and soil texture. However the diameters of both root and root tip increased, but root biomass decreased with increase of soil strength. There was no significant osmotic regulation at water potentials in the rooting media of ≥ - 0.2 MPa. Osmotic regulation commenced at < - 0.20 MPa and this partially compensated for the turgor loss from water stress. The wall yielding coefficient decreased with loss of turgor. The reduction in the root elongation rate with decreased water potential was an integrated effect of both decreased turgor pressure and reduced wall yielding coefficient. Roots osmotically regulated against increasing soil strength. No significant relationship between yield turgor pressure and both water potential and soil strength was observed. When soil air-filled porosity was non-limiting, root elongation rate in soil (∆R) was determined by soil matric potential (Ψm) and soil strength (Q) and was best described by a non-linear model: ∆R = α e-βQ + γѰm. The effect of water potential in decreasing root growth was most pronounced at low soil strength. Roots of radiata pine are able to penetrate higher soil strength at higher soil matric potential, and root growth of radiate pine seedlings ceased at higher soil matric potential in compacted soil than in loose soil.

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Pagliarini, Maximiliano Kawahata. "Genotype by environment interaction in slash pine and methodologies comparison for radiata pine wood properties /." Ilha Solteira, 2016. http://hdl.handle.net/11449/141895.

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Orientador: Ananda Virginia de Aguiar
Abstract: Exotic forest species have been introduced in Brazil in order to promote improvements in socioeconomic development and help to reduce the pressure caused to native forests. With growing demand for these species, research on genetic improvement has increased to find new, more productive germplasm and preferably in less time. Two species were used in the study: slash pine (Pinus elliottii Engelm. var. elliottii) and radiata pine (Pinus radiata D. Don). The first part of the study had the purpose to identify the stability, adaptability, productivity and genetic parameters, in addition to selection gain and genetic divergence in slash pine open pollinated second generation progenies considering phenotypic trait. Two tests were established, one in Ponta Grossa-PR with 24 progenies and one in Ribeirão Branco-SP with 44 progenies, both in Brazil, to identify the most productive genotypes for commercial planting areas in both sites. There was significant variation (p<0.01) among progenies for growth and form traits. The high coefficients of genetic variation for wood volume (14.31% to 16.24% - Ribeirão Branco-SP and 31.78% to 33.77% - Ponta Grossa-PR) and heritability (0.10 to 0.15 – Ribeirão Branco-SP and 0.36 to 0.48 – Ponta Grossa-PR) have shown low environmental influence on phenotypic variation, which is important for the prediction of genetic gain by selecting and confirming genetic potential in both places, especially Ponta Grossa. The effect of genotype x environment interact... (Complete abstract click electronic access below)
Resumo: Espécies exóticas de Pinus foram introduzidas no Brasil para promoverem o crescimento socioeconômico do país e ajudar na redução da pressão causada pelo uso de florestas nativas Com a crescente demanda por essas espécies, pesquisas em melhoramento genético tem aumentado na busca de novos germoplasma mais produtivos em menor tempo. Duas espécies foram utilizadas no presente trabalho: Pinus elliottii Engelm. var. elliottii e Pinus radiata D. Don. A primeira parte do trabalho teve a finalidade de identificar a estabilidade, a adaptabilidade, a produtividade e os parâmetros genéticos, além do ganho de seleção e diversidade genética em progênies de polinização aberta de segunda geração de P. elliottii var. elliottii considerando os caracteres fenotípicos. Foram estabelecidos dois testes, um em Ponta Grossa-PR com 24 progênies e outro em Ribeirão Branco-SP com 44 progênies visando identificar os genótipos mais produtivos para áreas de plantio comercial em ambos locais. Foi observada variação significativa (p<0,01) entre as progênies para os caracteres de crescimento e alguns caracteres de forma. Os altos coeficientes de variação genética para volume de madeira (14,31% a 16,24% - Ribeirão Branco e 31,78% a 33,77% - Ponta Grossa) e herdabilidade (0,10 a 0,15 – Ribeirão Branco e 0,36 a 0,48 – Ponta Grossa) mostraram baixa influência do ambiente na variação fenotípica, o que é importante para a predição do ganho genético mediante a seleção e confirmam potencial genético em ambos os loc... (Resumo completo, clicar acesso eletrônico abaixo)
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Pagliarini, Maximiliano Kawahata [UNESP]. "Genotype by environment interaction in slash pine and methodologies comparison for radiata pine wood properties." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/141895.

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Espécies exóticas de Pinus foram introduzidas no Brasil para promoverem o crescimento socioeconômico do país e ajudar na redução da pressão causada pelo uso de florestas nativas Com a crescente demanda por essas espécies, pesquisas em melhoramento genético tem aumentado na busca de novos germoplasma mais produtivos em menor tempo. Duas espécies foram utilizadas no presente trabalho: Pinus elliottii Engelm. var. elliottii e Pinus radiata D. Don. A primeira parte do trabalho teve a finalidade de identificar a estabilidade, a adaptabilidade, a produtividade e os parâmetros genéticos, além do ganho de seleção e diversidade genética em progênies de polinização aberta de segunda geração de P. elliottii var. elliottii considerando os caracteres fenotípicos. Foram estabelecidos dois testes, um em Ponta Grossa-PR com 24 progênies e outro em Ribeirão Branco-SP com 44 progênies visando identificar os genótipos mais produtivos para áreas de plantio comercial em ambos locais. Foi observada variação significativa (p<0,01) entre as progênies para os caracteres de crescimento e alguns caracteres de forma. Os altos coeficientes de variação genética para volume de madeira (14,31% a 16,24% - Ribeirão Branco e 31,78% a 33,77% - Ponta Grossa) e herdabilidade (0,10 a 0,15 – Ribeirão Branco e 0,36 a 0,48 – Ponta Grossa) mostraram baixa influência do ambiente na variação fenotípica, o que é importante para a predição do ganho genético mediante a seleção e confirmam potencial genético em ambos os locais, especialmente Ponta Grossa. O efeito da interação genótipo x ambiente é simples. As progênies plantadas em um local poderão também ser plantadas no outro. Dentre essas as C-197, C-189-1, C-084-2 e C-032-2 são indicadas para plantações tanto na região estudada do estado de São Paulo quanto do Paraná. Apesar de um número maior de progênies em Ribeirão Branco, constatou-se o mesmo número de agrupamentos de progênies pelo método UPGMA e de otimização de Tocher em ambos os testes. Existe diversidade genética entre as progênies de P. elliottii. Para programas de melhoramento, recomenda-se o cruzamento entre progênies de grupos divergentes para aumentar a variação genética, e consequentemente, o ganho genético nas gerações subsequentes, sem esquecer de se levar em consideração a performance do caráter de interesse. O objetivo do trabalho em P. radiata foi relacionar os resultados de características da madeira obtidas a partir de dois métodos Pilodyn e SilviScan visando validar uma metodologia eficiente para fenotipagem de um maior número de amostras. Um teste com 30 progênies de P. radiata foi estabelecido em Flynn na Austrália. As características avaliadas foram densidade da madeira, o ângulo microfibrilar e o módulo de elasticidade. A correlação genética e fenotípica entre os caracteres da madeira obtidas a partir dos dois métodos e a herdabilidade individual no sentido restrito foram estimadas. Os dados de Pilodyn apresentaram alta herdabilidade e alta correlação genética e fenotípica entre densidade de madeira e moderada com ângulo microfibrilar e módulo de elasticidade. Os resultados confirmam que o Pylodyn é um efetivo método indireto e rápido para avaliação de parâmetros genéticos para caracteres de qualidade madeira em P. radiata.
Exotic forest species have been introduced in Brazil in order to promote improvements in socioeconomic development and help to reduce the pressure caused to native forests. With growing demand for these species, research on genetic improvement has increased to find new, more productive germplasm and preferably in less time. Two species were used in the study: slash pine (Pinus elliottii Engelm. var. elliottii) and radiata pine (Pinus radiata D. Don). The first part of the study had the purpose to identify the stability, adaptability, productivity and genetic parameters, in addition to selection gain and genetic divergence in slash pine open pollinated second generation progenies considering phenotypic trait. Two tests were established, one in Ponta Grossa-PR with 24 progenies and one in Ribeirão Branco-SP with 44 progenies, both in Brazil, to identify the most productive genotypes for commercial planting areas in both sites. There was significant variation (p<0.01) among progenies for growth and form traits. The high coefficients of genetic variation for wood volume (14.31% to 16.24% - Ribeirão Branco-SP and 31.78% to 33.77% - Ponta Grossa-PR) and heritability (0.10 to 0.15 – Ribeirão Branco-SP and 0.36 to 0.48 – Ponta Grossa-PR) have shown low environmental influence on phenotypic variation, which is important for the prediction of genetic gain by selecting and confirming genetic potential in both places, especially Ponta Grossa. The effect of genotype x environment interaction is simple. Progenies planted in one site can also be planted in the other. Among these C-197, C-189-1, C-084-2 and C-032-2 progenies are suitable for plantations in both studied region of São Paulo and Paraná. Although larger number of progenies in Ribeirão Branco, it was found the same number of clusters through UPGMA and Tocher methods in both tests. There is genetic diversity among slash pine progenies. For breeding programs, it is recommended to cross progenies between different groups to increase genetic variation, and consequently the genetic gain in subsequent generations, not forgetting to take into account the performance of interest trait. The objective of the study in Radiata pine was relate wood quality traits obtained from two methods Pilodyn and SilviScan to validate an efficient phenotyping methodology for a greater number of samples. A test with 30 progenies of Radiata pine was established in Flynn Australia. The evaluated traits were wood density, microfibril ange and modulus of elasticity. Genetic and phenotypic correlation between traits of wood quality obtained from two methods and narrow-sense individual heritability were estimated. The Pilodyn data showed high heritability and high genetic and phenotypic correlation between wood density and moderate with microfibril angle and modulus of elasticity. The results confirm that the Pylodyn is an effective indirect and rapid method for evaluation of genetic parameters for wood quality traits in Radiata pine.

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Herritsch, Alfred. "Investigations on Wood Stability and Related Properties of Radiata Pine." Thesis, University of Canterbury. Chemical and Process Engineering, 2007. http://hdl.handle.net/10092/1203.

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Previous studies on wood instability have identified some wood basic properties which influence the timber distortion and shape changes while the wood is losing or gaining moisture. These properties include wood anisotropic shrinkage, equilibrium moisture content (EMC) in both desorption and adsorption, fibre saturation point (FSP) and water diffusion coefficient. This study investigated the stability related wood properties and their variations within the stems of the New Zealand grown radiata pine trees. The basic density, EMC and shrinkage for the earlywood and the latewood were also experimentally determined. In taking into account these properties and their variations, an analytical model was developed to simulate the wood distortion. The equilibrium moisture content was determined at 30Â°C and humidity range from 27% to 90%. It was found that the EMC difference between the earlywood and the latewood was negligible. The experimental results also show that the EMC decreases from pith towards the bark over the disc cross section and the trend is most obvious at high humidities (70-90%). Along the tree height, the EMC decreases from ground towards the top of the stem. The tangential shrinkage results were highly variable but, in general, the latewood has higher values than the earlywood. The opposite trend was found for the longitudinal shrinkage, higher values for the earlywood than the latewood. In the tree height direction, the tangential shrinkage was found to decrease with the tree height. This follows the same trend as the microfibril angle which in general also decreases with the tree height. The fibre saturation point (FSP) was determined from the tangential shrinkage values at different equilibrium moisture contents. These were taken as the intersection point of the tangential shrinkage line with the moisture content axis. The experimental results have revealed a trend that the FSP decreases from the pith towards the bark and also decreases with the tree height. Similar behaviour was found for the tangential and longitudinal swelling during the adsorption. The moisture transport within radiata pine was investigated based on the diffusion theory under transient and isothermal condition of 30Â°C. The moisture dependant diffusion coefficient was derived from the experimental data using the inverse analysis method. The surface emission coefficient was determined by taking into account the variable surface moisture content, wood density and the ambient conditions. In the experiments, 138 samples in total (46 samples for each XIV of the longitudinal, tangential and radial directions) were used and their diffusion coefficients were determined for both the adsorption and the desorption with moisture content ranging from 6% to 22%. The derived diffusion coefficients are comparable with the reported data in the literature. Further investigation of the wood type influence on the diffusion coefficient revealed that compression wood has the lowest diffusion coefficients in the three directions (longitudinal, tangential and radial) both in the desorption and in the adsorption. In addition, the moisture content has the least influence on the diffusion coefficient in the compression wood. Investigation on the effects of the wood density has shown that in general, the diffusion coefficient decreases with increasing wood density although the correlations are only significant for the longitudinal direction in desorption. An analytical model for the simulation of the wood twist was developed which is based on the geometry and geometrical changes of the grains aligning non parallel to the pith. A board consists of numerous such grains which change the length and shape with moisture content change. The model predictions confirm that the grain angle, the tangential and longitudinal shrinkage and the conical angle all affect the development of the board twist. However, the discrepancies between the model prediction and the experimental data are significant, partly due to the experimental uncertainties and partly due to the model errors. In this study, sound velocity in the longitudinal direction was measured for the test samples used in the shrinkage experiments. The results revealed that the correlations between the sound velocity and the volumetric shrinkage at oven dry are significant. Based on this finding, the relationship between the tangential shrinkage and the radial shrinkage, the tangential shrinkage can be predicted from the sound velocity measurements. As the tangential shrinkage has significant influence on the wood distortion, this method can be used to segregate logs which may be prone to wood distortion.

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Xu, Ping. "The mechanical properties and stability of radiata pine structural timber." Thesis, University of Canterbury. Forestry, 2000. http://hdl.handle.net/10092/7497.

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Investigating stiffness, strength and stability in radiata pine structural timber is significant to the civil engineering, forestry industry and genetic selection in New Zealand due to the following reasons: 1. Radiata pine provides about 90% structural timber for industry and is one of the major incomes of the forestry industry in New Zealand. 2. Stiffness, strength and stability are major quality criteria of structural timber. 3. Radiata pine stem has large proportion of corewood that tends to be low in stiffness, strength and stability. This study first presents the maps of average stiffness, average strength and average warp in radiata pine structural timber, obtained from sixty-two 27-year old, unpruned radiata pine trees. From these maps, one can conclude that the butt logs are problem logs, because the butt logs displayed the lowest stiffness, as well as the maximum bow and spring within the stems. The stiffness and strength distributions were compared with the typical distribution of wood density, which reveals that the wood density alone does not reflect the mechanical properties of radiata pine structural timber, because: 1) the denser butt logs exhibited the lowest stiffness among all log types; 2) the butt logs were not the strongest logs compared with other log types. Knots are found to be the most important factor weakening the mechanical properties and causing extra distortion in structural timber. 99% of the boards broke at a knot that is associated also with lower local stiffness. 70% of maximum bows and 40% of maximum springs occurred off the expected mid-span, which may be attributed to the deflections introduced by larger margin and edge knots. In order to estimate the failure strength non-destructively, this study examined the failure features of the weakest point in detail, including the local stiffness at the failure zone, the failure pattern of knots and the failure frequency in relation to growth and features of knots. The results of this study reveal that non-destructive estimation of strength at the likely weakest point in structural timber is possible.

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Sharma, Rajesh kumar. "Comparison of development of radiata pine (Pinus radiata D. Don) clones in monoclonal and clonal mixture plots." Thesis, University of Canterbury. School of Forestry, 2008. http://hdl.handle.net/10092/1577.

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The development of radiata pine (Pinus radiata D. Don.) clones was compared in monoclonal and clonal mixture plots planted in an experiment established at Dalethorpe, Canterbury, New Zealand with ten radiata pine clones in September 1993. Clones were deployed in a randomised complete block plot design with three replications. Each replication contained ten treatments of monoclonal plots and one in which all the clones were intimately mixed in equal proportions. Clones significantly differed in initial morphologies, survival and stem slenderness. Sturdiness and initial heights were found to be the best predictors of initial survivals. The study revealed that mode of deployment did not affect overall productivity, but individual clones exhibited significantly different productivities between modes of deployment. All clones contributed similarly to overall productivity in the monoclonal mode of deployment, whereas the contribution of clones in the clonal mixture mode of deployment was disproportionate. A minority of the clones contributed a majority of overall productivity in the clonal mixture mode of deployment. The inclusion of competition index as an independent variable in a distance-dependent individual tree diameter increment model explained a significant amount of variability in diameter growth. The use of an inverse-squared distance to neighbouring plants in the competition index provided a slightly superior fit to the data compared to one that employed a simple inverse of distance. Addition of genotype information in the competition index further improved the fit of the model. Clones experienced different levels of competition in monoclonal and clonal mixture modes of deployment. Competition in monoclonal plots remained uniform over time, whereas some clones experienced greater competition in clonal mixture plots which led to greater variability in their tree sizes. This study indicated that single tree plot progeny test selections and early selections may miss out some good genotypes that can grow rapidly if deployed monoclonally. Stand level modelling revealed that clones differed significantly in modeled yield patterns and model asymptotes. Clones formed two distinct groups having significantly different yield models. The study also demonstrated that models developed from an initial few years’ data were biased indicators of their relative future performances. Evaluation of effectiveness of the 3-PG hybrid model using parameter values obtained from destructive sampling and species-specific values from different studies revealed that it is possible to calibrate this model for simulating the productivity of clones, and predictions from this model might inform clonal selections at different sites under differing climatic conditions. Destructive sampling at age 5 years revealed that clones significantly differed in foliage and stem biomass. The differences in productivities of clones were mainly due to differences in biomass partitioning and specific leaf areas. Clones significantly differed in dynamic wood stiffness, stem-slenderness, branch diameter, branch index and branch angle at an initial stocking of 1250 stems/ha. Mode of deployment affected stem slenderness, which is sometimes related to stiffness. Although dynamic stiffness was correlated with stem slenderness and stem slenderness exhibited a significant influence on stiffness, clones did not exhibit statistically significant differences in dynamic stiffness. Increasing initial stocking from 833 stems/ha to 2500 stems/ha resulted in a 56 % decrease in branch diameter and a 17 % increase in branch angle. Trees in the monoclonal mode of deployment exhibited greater uniformity with respect to tree size, stem-slenderness, and competition experienced by clones compared to those in the clonal mixture mode of deployment. Susceptibility of one clone to Woolly aphid suggested that greater risks were associated with large scale deployment of susceptible clones in a monoclonal mode of deployment. This study also indicated that if the plants were to be deployed in a monoclonal mode then block plot selections would have greater potential to enhance productivity.

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Wang, Eric Yunxin. "Properties and Distortion of Douglas-fir with Comparison to Radiata Pine." Thesis, University of Canterbury. Chemical and Process Engineering, 2009. http://hdl.handle.net/10092/3556.

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The objectives of this study were to investigate stability related basic wood properties and to determine stability performance of New Zealand grown Douglas-fir and those of radiata pine wood. In this study, nine 60-year old Douglas-fir trees and thirteen 26-year old radiata pine trees were selected from forests in Canterbury region. From these trees, 36 discs of 200 mm thick (13 for Douglas-fir and 23 for radiata pine) and 388 boards with dimensions of 100mm x 50mm x 4.8m (210 fro Douglas-fir and 178 fr radiata pine) were prepared. From the prepared discs, 515 specimens (204 for Douglas-fi and 211 for radiata pine) were prepared for green moisture content (MC) and basic density measurements, The same total number of 515 specimens (205 for Douglas-fir and 210 for radiata pine) were also prepared for shrinkage measurements. From the green MC specimens, green weight, volume and oven-dry weight were measured while for the shrinkage specimens, dimensions and weights were measured at equilibrium for nine humidity conditions. These data were used to analyse basic wood properties and moisture uptake characteristics for both Douglas-fir and radiata pine. Variation of shrinkage within a tree and between trees was also studied for both species. After this, selected specimens (36 for Doulas-fir and 36 for radiata pine) were further tested in water immersion for water repellence examination. The 388 full size boards (100mmx50mmx4.8m) were used for studies on distortion and acoustic properties at a sawmill (Southland Timber Ltd.). Dimensions, weights and acoustic velocity were measured from each board before and after drying. These data were used to analyse distortion and strength characteristics for both Douglas-fir and radiata pine. Comparison of the relative stability of full sized Douglas-fir and radiata pine structural timber was investigated in this study. The results from small sample study confirmed that Douglas-fir is much stronger, has lower longitudinal shrinkage and lower gradient in corewood which can be used to explain the better dimensional stability of Douglas-fir than radiate pine although there is significant variability in the shrinkage for both Douglas-fir and radiate pine. In water immersion tests, Douglas-fir has better water repellency property than radiata pine over 2000 hours period during water immersion. Under the same commercial practice in sawing and kiln drying, it is clearly shown that Douglas-fir timbers were straighter with lower levels of distortion than radiata pine at similar final moisture content. It is also interesting to note that the final moisture content in a range of 13-18% for Douglas-fir did not have significant impact on timber distortion but a negative trend was observed for radiata pine with MC in a range of 9 -14%. Tree heights showed clear influence on twist for radiata pine timbers, but it was not clearly observed from Douglas-fir timbers. Corewood proportion is found to have negative impact on the timber distortion for both Douglas-fir and radiata pine. Douglas-fir timbers showed much higher average acoustic MOE value than radiata pine timbers at similar final moisture content. Because of the various proportion of corewood, the shrinkage varied greatly along the stem height and along the disc radius direction for the two species. This variation caused the difference of distortion between corewood, outerwood and transition wood, but the difference between butt log, middle log and top log is inconsistent. Therefore, it is recommended that the corewood proportion to be a criterion for the timber pre-sorting. Variation of stability performance between trees was also found to be significant for the two species, and methods need to be developed for log sorting as well to reduce the timber distortion degradation. Non-destructive testing method such as acoustic tool may be offered to be a new approach for sorting logs, but it is also necessary to be aware of the significant difference between species. The outcome from this project includes better understanding of Douglas-fir for structural applications. The conclusion can be drawn that Douglas-fir has superior quality for its strength, durability and moisture resistance. Douglas-fir is also claimed to have uniform properties and thus to be more stable compared to radiata pine. Douglas-fir timbers showed much higher acoustic MOE value than radiate pine timbers as similar final moisture content.

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Alzamora, M. Rosa Maria. "Valuing Breeding Traits for Appearance and Structural Timber in Radiata Pine." Thesis, University of Canterbury. Forestry, 2010. http://hdl.handle.net/10092/5077.

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The aims of this thesis were; firstly, to obtain economic values for radiata pine traits to produce appearance and structural lumber, and secondly to analyze the selection of efficient logs and profitable trees to substantiate the development of breeding objectives for solid wood quality. The thesis included three approaches to value wood attributes: hedonic models, partial regressions and stochastic frontiers. Hedonic models generated economic values for pruned and unpruned log traits to produce appearance grades. Values for small end diameter were 0.33, 0.19 and 0.10 US $/mm, and for form 2.6, 1.4 and 0.63 US $ for the first, second and third log respectively. The value of mean internode length was 0.19 US $/cm. Branch size traits were non-significant to explain the log conversion return (p>0.05). The economic value of log traits to produce structural lumber with stiffness of 8, 10 and 12 GPa was estimated with a partial regression. The values were 1.1, 29.7, 0.3 and -0.4 NZ $/m3 for small end diameter (cm), stiffness (GPa), basic density (kg/m3) and largest branch (mm) respectively. Small end diameter and stiffness explained 73% of the variation of log conversion return. The economic values for structural attributes were also derived from a Cobb Douglas stochastic frontier, resulting in 2.1 NZ $/cm for small end diameter and 15.8 NZ $/GPa for stiffness. The change of values between approaches can be attributed to differences of model formulation. The stochastic frontier used aggregate volume of lumber with stiffness of 8 GPa or higher. The partial regression used the economic value of every lumber product derived from the logs, making it more sensitive to changes in wood quality. Data envelopment analysis (DEA) used structural traits and their economic values to assess the technical and economic efficiency of logs to produce lumber with stiffness of 8, 10 and 12 GPa. The most efficient logs had 1:4 ratios between stiffness and small end diameter, whereas logs that did not generate structural lumber had ratios closer to 1:8. Trait economic values from the partial regression analysis were used as attribute prices to estimate cost efficiency. Efficiency measures were significantly correlated with stiffness and log conversion return; however, they were non-significantly correlated with small end diameter and log prices. The technical efficiency of logs to produce structural lumber was also determined using a Cobb Douglas stochastic frontier which determined that the most efficient logs were characterized by a 1:5 ratio between stiffness and small end diameter. Selection of trees for deployment was analyzed with a portfolio model, where risk was represented as the mean absolute deviation of tree returns due to the variability of volume, stiffness and resin defects. Under high variability (risk), the model selected structural trees with large stiffness and high return. These results suggest an opportunity for narrowing genetic variability (via clonal or family forestry) to make the returns from radiata pine structural grades lumber less risky. As variability decreased the portfolio model opted for trees that produced appearance and structural lumber. These trees had a stabilizing effect on their returns, as there were phenotypic tradeoffs between stiffness and volume under optimistic and pessimistic growing scenarios. These results showed the benefits of product diversification at the tree level.

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Perry, Christopher. "Economic analysis of a target diameter harvesting system in radiata pine." Thesis, University of Canterbury. School of Forestry, 2013. http://hdl.handle.net/10092/9899.

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Target diameter harvesting (TDH) is a forest management system in which all stems above a set minimum diameter are harvested on a periodic basis. There is evidence in the literature that TDH can achieve a rate of return on a similar scale to a clearfelling regime, with added benefits of regular cash flow from partial harvests, and preservation of non-timber values. Economic analysis was carried out on 12 years of TDH using permanent sample plot (PSP) data from Woodside Forest, a 30ha plantation of radiata pine (Pinus radiata). The Woodside Forest management regime has a target diameter of 60cm, and a harvest cycle of two years. Economic analysis considered the option to partial harvest or clearfell every two years, and compared the outcome of each option in terms of land expectation value (LEV). Comparisons are made between regimes with different numbers of partial harvests, assessing the effect of TDH on stand LEV. Results show that in three of four applicable stands, LEV reached a maximum at ages 30 – 32, (near the time when partial harvesting commenced), and reduced slowy with increased numbers of partial harvests. This shows there is a small opportunity cost associated with choosing TDH over a clearfell system. The effect of revenue from early partial harvesting operations on LEV was small as the majority of stand value is still in the standing crop. This limited the conclusions that can be drawn form this study due to the short time frame analyzed. The study was limited by a small dataset which did not accurately represent average stand values. Because of this, no attempt to quantify the value of the opportunity costs was made. Despite this, the results support the notion that TDH can achieve economic returns similar to clearfelling in radiata pine forests.

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Tsehaye, Addis. "Within- and between-tree variations in the wood quality of radiata pine." Thesis, University of Canterbury. Forestry, 1995. http://hdl.handle.net/10092/7147.

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This study was conducted to determine the within- and between-tree variations in the physical and mechanical properties of Pinus radiata (radiata pine). Forty eight trees from a 25-year-old plantation on the Canterbury plains near Dunsandel in the South Island of New Zealand were felled and cross-cut to give three 3.6 meter logs. Each log was identified by tree number and position up the height of the tree (butt, middle and top log). At the sawmill the logs were sawn, first by removing 40 mm thick slices known as flitches from opposite sides of the trunk until a 100 mm thick plank known as a cant was left at the centre. The flitches were re-cut at the breast bench circular saw to yield timbers of nominal dimensions 100x40 mm. In re-cutting the 100 mm wide cant gave 3-5 boards depending on the diameter of the log. The position of every board was recorded relative to the pith and numbered. A total of 915 boards from the 48 trees (144 logs) were obtained. The boards were filleted (i.e. stacked with uniform and sufficient spacing between each layer both in the vertical and horizontal directions so as to ease air circulation) and air-dried to approximately 12% moisture content. After drying the boards were dressed to 90x35 mm and grouped into .one of the four Australian structural grades (F4, F5, F8 and F11) as each board passed through a stress grading machine. The modulus of elasticity of the boards was measured both in flatwise bending and axial tension. The strength of the boards was determined by destructive testing in tension and compression parallel to the grain. After failure in tension short clear planks (i.e. planks with no knots and any other natural defects) were cut from each board. From these short planks small clear specimens were prepared for the determination of stiffness, bending strength and compression strength parallel to the grain. The investigation of density, stiffness and strength in relation to the vertical and radial positions within a tree revealed that there is a significant variation in all properties with changes in radial positions across the diameter, and a significant variation in strength properties, but not stiffness with change in vertical position up the height of the tree. Regarding between-tree variation, all properties changed significantly. With reference to the production of structural framing timber, stiffness and density were compared as criteria for sorting trees and identifying superior material within logs. This analysis revealed that stiffness is a better criterion for selecting superior trees within the natural population of a forest stand, to improve the value of mill production and to achieve a better outturn in higher value grades (F5 and above). A regression analysis between the properties of the in-grade timber and clearwood showed that there is a very strong relationship between the modulus of elasticity of clearwood and that of the in-grade timber. As expected there was a general decrease in strength and stiffness of the graded timber as the grade value decreased from F11 to F4. Strength and stiffness values in tension, bending and compression have been compared with the current New Zealand, Australian and European code design values, generally giving good recovery of higher value grades (F5 and above), especially for strength.

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14

Wells, Karen E. "Development of a Laboratory Protocol for the Micropropagation of Monterey Pines (Pinus Radiata), Año Nuevo Stand." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/76.

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Monterey pine (Pinus radiata), a native tree to California and two Mexican islands, is important both ecologically and economically. Outside native stands, Monterey pines are grown for landscaping in California and on plantations around the world. Pitch canker, a disease caused by the fungus Gibberella circinata Nirenberg & O’Donnell (Fusarium circinatum Nirenberg and O'Donnell) is threatening the survival of Monterey pines. The disease currently affects Monterey pines in many parts of the world including the native stands. No effective chemical or biological control is available but some Monterey pines show resistance to the disease. The purpose of this project was to develop a working protocol for producing genetic clones of the resistant pines through micropropagation. These genetic clones will be used for outplanting in places outside the native stands for ornamental and plantation purposes. This project analyzes the results of ten trials with varied parameters and bases the final protocol on the parameters used in the trial that induces the growth of new shoots. The final protocol developed in this project describes, step-by-step, the media preparation for the initiation, plant material collection, surface sterilization of plant material, plating in media and initiation of shoots on explants. The protocol calls for collecting shoot tips with hardened buds that have not yet elongated, then washing the shoot tips in sterile water with Tween 20 for 15 minutes. The shoots tips are then surface sterilized in a 50% bleach solution for 20 minutes. The explants are broken into disks (to minimize damage to the cells) by inserting the tip of a scalpel and tilting it slightly. The initiation media shown to induce growth consists of ½ strength LePoivre basal salt mixture, 5mg/L benzylaminopurine, 3% sucrose and 0.8% agar and is adjusted to a pH of 5.7, then autoclaved for 20 minutes. The explants are inserted into solidified media and incubated in a growth chamber programmed for 16 hours of light and 8 hours of dark with temperatures of 27ºC and 22ºC and light irradiance of 80µEm-2s-1. After 1 month the protocol calls for transferring the growing shoots to elongation media with full LP basal salts and transferring every month. When the number of desired shoots has been reached the forthcoming protocol for rooting can be followed.

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15

Thomas, Jimmy. "An investigation on the formation and occurrence of spiral grain and compression wood in radiata pine (Pinus radiata D. Don.)." Thesis, University of Canterbury. Biological Sciences, 2014. http://hdl.handle.net/10092/9654.

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Radiata pine (Pinus radiata) is the most important plantation tree in New Zealand forestry, and factors that reduce the quality of wood cause significant economic loss. Two of the most important of these issues are compression wood and spiral grain. Compression wood is a type of reaction wood, formed when a tree moves away from the vertical, and is characterised by biochemical and structural changes within the wood that reduce its quality and value. Spiral grain, however, is the alignment of the wood grain in a helix around the tree’s axis and away from the vertical. Again, this reduces the structural qualities of the wood and thus its value. Spiral grain and compression wood are notorious for their deleterious effect on the quality of wood produced and are very important for the forest industry due to the huge economic loss they cause. The demand for reliable tools to evaluate these wood quality issues in clonal planting material at an early stage, within 3 years of germination rather than at 8 to 15 years as in current practise, is of ever increasing importance from plant breeders and other industry stake holders. Therefore this research was undertaken with an overall aim to develop quick, easy and reproducible techniques to evaluate young radiata pine clones (up to 3 years old) based on compression wood content and presence of spiral grain. This is important because a shortened breeding cycle could provide significant economic benefits to the forest industry. The incidence of these commercially important wood quality parameters has been studied in this thesis in research conducted on young trees (1 to 3 years old). The research described in this thesis used a variety of different imaging approaches to investigate wood structure, including polarised light and confocal microscopy, and X-ray tomography and circular polarised light scanning. The images achieved have been analysed using a range of different software, including Photoshop, ImageJ and Matlab bringing a quantification approach to the imaging. Compression wood was quantified in young clonal material using images collected with a commercial document scanner, and processed using image analysis tools available in Photoshop. An easy, reliable and robust, automatic image analysis protocol was successfully developed and tested for the detection and quantification of compression wood in these young trees. This new technique to detect and quantify compression wood was based on the thresholding of the blue channel of the scanned RGB image as this was demonstrated to contain the greatest image contrast. Development of this new technique may reduce the waiting time for screening clonal planting materials based on compression wood content. To understand the organisation of the grain at a cellular level within these young trees, confocal microscopy techniques were utilised. The cell wall characteristics and fluorescence properties of compression wood in comparison with normal wood were investigated using a new cellulose specific dye, pontamine fast scarlet 4B. Staining protocols for this dye for confocal microscopy were optimised, and the potential of measuring the microfibril angle of the S1 and S3 layers of the pontamine treated opposite wood was demonstrated through either direct observations of these layers, or through the property of bifluorescence where the dye is excited only when aligned parallel to the polarisation of the incident light. Despite extensive work with confocal microscopy, this technique proved to be unsuitable for investigations of spiral grain because although it provided cellular detail, imaging was limited to the surface layers of sections, and the area over which observations were required was prohibitive. Instead of confocal microscopy, the incidence of spiral grain in young stems was investigated in two completely new ways. Resin canals, which are formed from the same cambial initials as the tracheids and which align with the grain, were used as a proxy to demonstrate the grain changes. A novel technique, using circular polarised light and a professional flatbed scanner, was developed to image whole serial transverse sections of the young stems to detect the resin canals. Using ImageJ, the number and location of resin canals was measured on vertical controls, and trees that had been rocked and leaned. The number and frequency of resin canals were less in tilted trees, especially in compression wood, compared to the higher number of canals formed in the rocked trees. More importantly, a combination of serial sectioning and this approach allowed a 3-dimensional view of the orientation of resin canals inside a stem to be generated with ImageJ, and the angles of these canals could be measured using Matlab. The resin canals were oriented with a left-handed spiralling near the stem surface whereas the canals near to the pith were nearly straight, consistent with previous observations of the development of spiral grain in radiata pine. However, it was observed that while vertical trees had a symmetric pattern of grain and grain changes around the stem, this was not the case in tilted trees. In these, the opposite wood often had severe spiral grain visible through formation of twist whereas the compression wood formed on the lower side had bending. Consistent with this, grain associated with compression wood was significantly straighter than in opposite wood. This hitherto unknown link between the incidence of compression wood and spiral grain was investigated and explained on the basis of the characteristics of resin canals in these types of wood. X-ray micro-tomography was also used to investigate resin canals in the stubs from which serial sections were collected. The 3D reconstructions of the resin canals showed exactly the same patterns as observed by polarised light scanning.

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16

McPherson, Angus J. "Market opportunities and strategies for New Zealand grown radiata pine in the UK." Thesis, Bangor University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333689.

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17

Pongracic, Silvia School of Biological Sciences UNSW. "Influence of Irrigation and Fertilization on the Belowground Carbon Allocation in a Pine Plantation." Awarded by:University of New South Wales. School of Biological Sciences, 2001. http://handle.unsw.edu.au/1959.4/18164.

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The aboveground and belowground productivity of forest systems are interlinked through complex feedback loops involving tree, soil and environmental factors. With a predicted significant change in environmental conditions through the enhanced greenhouse effect, it is important to understand the response of forest systems to these new conditions. An increase in atmospheric CO2 is predicted to increase photosynthesis, and therefore whole plant productivity at the individual tree level. However this increase in photosynthesis may result in greater requirements for nutrients, particularly nitrogen (N). In order to acquire any additional available N, trees may respond by increasing their proportional allocation of C belowground to the root system. This study aimed to quantify the belowground C allocation in a mature forest system consisting of a single species on a single site, but with different levels of water and nutrient stress. The belowground carbon dynamics of a range of irrigated and fertilized Pinus radiata stands in Australia were investigated during 1992 and 1993. Belowground carbon allocation was estimated using the model proposed by Raich and Nadelhoffer (1989) where belowground C allocation is the difference between soil respiration and carbon input through litterfall, plus coarse root production and an adjustment for any change in soil and litter layer carbon pools. This model is best described by the equation: Belowground C = Csoilresp ?? Clitterfall + Ccoarseroot+ ???Cforest floor+ ???Csoil Soil respiration, measured using a modified soda lime absorption method either every 2 weeks or every 4 weeks for 2 years, showed a range in daily soil C flux from 137 ?? 785 mgCO2.m-2.h-1. Soil respiration showed seasonal trends with summer highs and winter lows. Limited fine root biomass data could not indicate a strong relationship between measured soil respiration and fine root (>2mm diameter) biomass. Fifty three percent of the variation in soil respiration measurements in irrigated treatments was explained by a linear relationship between soil respiration, and soil temperature at 0.10 m depth and litter moisture content. In non-irrigated treatments, 61% of the variation in soil xix respiration measurements was explained by a linear relationship between soil temperature at 1 cm depth and soil moisture content. Inter-year variation was considerable with annual soil respiration approximately 20% lower in 1993 compared with 1992. Annual soil C flux was calculated by linear interpolation and ranged from 3.4 ?? 11.2 tC ha-1 across the treatments. Soil C pools remained unchanged over 10 years between 1983 and 1993 for all combinations of irrigated and fertilized stands, despite significant aboveground productivity differences over the decade. Measurements of standing litter showed a change between 1991 and 1993 for only 2 out of the 10 treatments. These two treatments had belowground C allocation estimated both with and without an adjustment for a change in standing litter. Annual litterfall C ranged almost four fold from 0.6 ?? 2.2 tC ha-1 between the treatments in 1992 and 1993, and fell within the ranges of measured litterfall over 10 years at the field site. Again inter-year variation was large, with the 1993 litterfall values being approximately 97% greater across all treatments compared with 1992 values. Belowground carbon allocation was calculated using C fluxes measured at the field site, and ranged 3 fold from 4.4 ?????? 12.9 tC ha-1 between the treatments during 1992 and 1993. In 1993 the belowground C allocation was approximately 30% lower across all treatments compared with 1992 calculations. This was due to an approximate 23% reduction in annual soil C flux, a 97% increase in litterfall C and an 18% reduction in coarse root production between 1992 and 1993. The field site was N limited, and differences in belowground C allocation could be shown across irrigated treatments with different N limitations. As N availability increased belowground C allocation was decreased in the irrigated treatments. It was difficult to determine differences in belowground C allocation caused by water stress as the effects of water and N limitation were confounded. An increase in N availability generally indicated an increase in coarse root and litterfall C production, which were reflected in increased aboveground productivity. In high N treatments the coarse root fraction of belowground C allocation comprised approximately 50% of the total belowground C allocation, whereas in the N stressed treatments coarse roots only comprised 20% of the total belowground allocation The mechanistic model BIOMASS was used to estimate annual gross primary productivity (GPP) for the different treatments at the field site. BIOMASS estimated GPPs of between 30-38 tC ha-1 for the different treatments during 1992 and 1993. The measured belowground carbon allocation ranged from 16 ?? 40 % of simulated GPP, with the lower proportion allocated belowground in the irrigated and high fertility stands. Aboveground competition through the absence of thinning also appeared to reduce allocation belowground in non- irrigated stands. A direct trade off between bole and belowground C could not be demonstrated, unless data were separated by year and by the presence or absence of irrigation. Where data were separated in this manner, only three data points defined the reasonably strong, negative relationship between bole and belowground C. The value of this relationship is highly questionable and should be interpreted with caution. Thus a decrease in belowground C allocation may not necessarily indicate a concomitant increase in bole C allocation. Inter-year variation in a number of C pools and fluxes measured at the field site was at least as great as the variation between stands having different water and N limitation. Extrapolation of belowground productivity estimates from a single years data should be undertaken cautiously. The work undertaken in this study indicated that for a given forest stand in a given soil type, an increase in N availability reduced the absolute and relative C allocated belowground. However this decrease in C belowground may not directly translate as an increase in stem growth or increased timber production. Forest productivity in an enhanced greenhouse environment is likely to result in an increased allocation of C belowground due to increased N limitation, unless adequate N is present to support a more active canopy. Further work is required to more fully understand the dynamics of the belowground system in a changing environment. However further research should focus on mature forest systems in order to isolate the impacts of natural ageing changes from perturbation effects on the forest system. This would be best undertaken in long term monitoring sites where a C history of the stand may be available.

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Kirongo, Balozi Bekuta. "Modelling growth responses of juvenile radiata pine (Pinus radiata D. Don) clones subjected to different weed competition levels in Canterbury, New Zealand." Thesis, University of Canterbury. Forestry, 2000. http://hdl.handle.net/10092/7496.

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For a given site, species, genotype and management regime, tree growth is related to the amount, and temporal- and spatial-distribution of foliage, as governed by the prevailing below- and above-ground environment and intercepted photosynthetically active radiation. Canopy foliage budgets, therefore can provide first hand information about how trees cope with adverse environmental conditions and resource deficits in more subtle ways than height and diameter which are not as sensitive to changes in resource availability as leaf area. Process-oriented research, aimed at quantifying needle mortality within canopies and foliage growth dynamics of young radiata pine clones growing under varying competition gradients, therefore has the potential to improve decision tools for foresters charged with establishing tree crops. During this study growth responses of juvenile radiata pine (Pinus radiata D. Don) clones to variable weeding micro-environments during the first 3 years after outplanting were evaluated. The study was established in a dry site on the Canterbury plains of the South Island of New Zealand. A complete randomised block design replicated three times in a split-plot layout was used. Four weeding treatments; 1) complete weeding, 2) 2 m diameter spots, 3) 1 m diameter spots around plants and 4) a control, formed the main plots while seven clones formed the sub-plots. Leaf area and specific leaf area spatial distribution as well as fascicle mortality in time and space were quantified. Annual crown foliage budgets of 3 of the clones were evaluated using regressions developed from limited destructive sampling and image analysis techniques. Changes in mean relative growth rate (RGR) with tree size and age were evaluated by quantifying the morphological and physiological terms of the RGR expansion, to allow for changes in these terms; RGR = ULR * SLA * LWR where, RGR = relative growth rate, ULR = unit leaf rate, SLA = specific leaf area and LWR = leaf weight ratio. Relative growth rate declined with tree age and size for trees in all weeded treatments but increased with age and size for trees in the unweeded control. The decline in RGR was mainly due to reduced ratio of dry matter turn over to leaf area i.e. unit leaf rate. Of tree age and size, size was the major factor influencing the decline in RGR. Of the 3 clones studied in detail, clone 3 had a different above ground carbon allocation strategy to clones 1 and 2, especially as regards leaf weight ratio and leaf area ratio. Weeding influenced tree growth considerably. Significant clonal differences in height and basal-basal area were found. Trees growing in weed-free environments made favourable use of their micro-environments and significant genotype-by weeding interaction was present for height. However, no "rich-kid" effect (some trees growing in weed-free micro-environments performing poorly) was found. Provisional models of height, basal-basal area and tree survival integrating weeding and clonal effects were also developed. One of the significant findings from this study was the strong evidence against the constant RGR model which has been used by many researchers of tree growth analysis. The results further demonstrated that trees growing with weeds were predisposed to perform poorly due to reduced canopy production as well as having higher proportions of older, less efficient foliage. The results from this study lay the framework to explicitly quantify clonal responses to resource deficits arising from management inputs using variables directly involved in canopy production (i.e. leaf area).

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Olsen, Colin Andreas Dupont. "Empirical process modeling of the acid catalyzed steam pretreatment of radiata and lodgepole pine." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43807.

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Ethanol, an alternative liquid fuel, can be produced from sugars derived from lignocellulosic biomass in a bioconversion process that involves pretreatment, enzymatic hydrolysis, and fermentation. Among the different types of biomass investigated for bioconversion, softwoods are readily available in Canada, the US, and Scandinavia. Acid catalyzed steam pretreatment is a preferred method for softwoods due to its ability to effectively recover hemicellulose-derived sugars at moderate operating conditions. More severe conditions are generally required to produce a substrate readily hydrolyzed by enzymes, but because sugar degradation also occurs at these conditions, steam pretreatment is essentially a compromise. Prediction of sugar recoveries from steam pretreated and enzymatically hydrolyzed softwood is desirable for the purposes of process control and steam pretreatment reactor design. In this thesis, efforts were made to determine whether response surface methodology or the thermal severity factors Ro and CS were better suited to the development of empirical models of steam pretreatment. The construction of the thermal severity factor models highlighted the predominance of temperature and time in determining the direct outcomes of the acid catalyzed steam pretreatment of radiata pine. Within a comparison of several response surface methodology models, a hybrid experimental design produced the most robust model because it was developed in conjunction with a narrow process space. Moreover, it was apparent that the response surface methodology models possessed the greater capacity for predicting the direct outcomes of steam pretreatment. In an attempt to overcome limitations identified in the first portion of this thesis, the predictive capability of response surface methodology was further tested using lodgepole pine ranging in chip size and moisture content. The additional model created demonstrated that response surface methodology could successfully account for feedstock characteristics as well as steam pretreatment operating conditions. Moisture content, but not chip size, was shown to have a significant influence on the combined sugar recovery obtained after SO2 catalyzed steam pretreatment and subsequent enzymatic hydrolysis. In addition, model development was conducted in this portion of the thesis such that the model could form the basis of a more dynamic simulation of the entire softwood to bioethanol process.

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Brassey, Christina. "Analysis of a Pinus radiata Seed Stock Field in the Native Año Nuevo Stand in California." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/219.

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This study was a part of the international collaborative IMPACT project, which aims to address the potential threat that the pitch canker disease poses to the use of Pinus radiata D. Don in plantations in New Zealand, Australia, and Chile. A field trial of 264 seedstocks was planted adjacent to a native stand of pitch canker infected P. radiata on the central coast of California, and disease symptom development was recorded over a period of 3 years. The results did not correlate with a greenhouse study of the same seedstocks inoculated with Fusarium circinatum Nirenberg & O'Donnell, the causal agent of pitch canker. Three main types of symptoms were identified (branch flagging, pitchy buds, and chlorotic tips), and preliminary isolation analyses suggest that the disease observed is actually caused by Diplodia pinea (Desm.) Kickx. Survival analysis showed that the effect of tree genetic origin was significant to its time to disease, and that spatial location in the plantation was also significant. Average nearest neighbor analysis showed disease distribution to be significantly clustered, which also suggests that the disease is not pitch canker, but diplodia blight. This experiment illustrates the difficulty in performing naturally infected field trials when another similar-looking fungal disease is also present. It also provides data on seedstock resistance to diplodia blight, another fungal disease important to P. radiata forest managers.

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Emebiri, Livinus Chinenye, and -. "Detection and Genetic Mapping of Quantitative Trait Loci Influencing Stem Growth Efficiency in Radiata Pine." The Australian National University. Department of Forestry, 1997. http://thesis.anu.edu.au./public/adt-ANU20010822.164445.

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Needle-to-stem unit rate (NESTUR) is a stem growth index of conifer seedling trees that measures the efficiency of stemwood production per unit of needle growth. Five experiments were carried out in this thesis using progenies of two unrelated full-sib radiata pine crosses. The initial experiment (experiment 1) applied the bulked segregant analysis technique to determine whether RAPD analysis could be successfully extended to the development of molecular markers for NESTUR in radiata pine. The NESTUR values of 174 progenies of the full-sib family 12038 x 10946 were determined. Based on the genotypic analysis of the individuals, two quantitative trait loci (QTL) controlling NESTUR were identified at ANOVA P-levels of 0.01-0.001. An absence of RAPD fragment markers generated by primers OPE-06 and OPA-10 was associated with low NESTUR values, while primer UBC-333 generated a 550 bp band that was associated with high NESTUR values. Linkage to components of NESTUR (increments in stem diameter and stem volume) was demonstrated for one of the QTL, while the other was unique to NESTUR, and not shared with the components. There was a significant interaction between the two QTLs. Presence of OPA-101200 locus appeared to inhibit expression of the QTL linked to UBC-333 [subscript 550]. ¶ To further analyse the quantitative trait loci (QTLs) controlling NESTUR, a linkage map was constructed from RAPD markers segregating in 93 haploid progeny of another full sib cross (30040 x 80121) (experiment 2). Two hundred and sixty-two (262) markers were mapped to 14 linkage groups of at least 7 markers, ranging in size from 39 to 183 cM. The 14 linkage groups covered approximately 1511 cM of genetic map distance. ¶ In experiment 3, the linkage map was used to map QTLs controlling NESTUR, as well as increments in seedling stem diameter, volume, and height and needle volume. Altogether, five putative QTLs were detected for NESTUR, with explained variation ranging from 9 to 22%. Of the five QTLs detected, 3 were coincidental with those for stem growth in height, diameter and volume. The two QTL positions that were unique to NESTUR were flanked by QTLs for the component traits. Together, effects of the five QTLs explained 48% of the total phenotypic variation for NESTUR. ¶ Ability of identified markers to predict the phenotype and seedlings with growth potential was assessed in the cross 30040 x 80121, using six RAPD markers associated with NESTUR at ANOVA P-levels of 0.01-0.001 (experiment 4). The correlation between observed NESTUR and predicted values was 0.70. Differences in observed vs. predicted values were not large and did not indicate serious misclassifications, such as classification of an upper ranking individual into the lower group, or vice versa. ¶ Over a two-year growth period, the ability of NESTUR to predict stem growth was strongly affected by seedling age. In contrast, markers linked to NESTUR showed a consistent ability to predict stem growth, irrespective of seedling age. Compared with the top 1% of the original population, seedlings selected for their genotypic values showed a higher stem volume growth of 103% in the first year, and 76% in the second year. ¶ The expression of QTLs for stem volume, stem diameter, height, number of branches, number of whorls, and branches/whorl were compared at 5, 12, and 24 months of age. Two QTLs detected for height showed contrasting expression over two years, one was gradually reduced from LOD of 2.70 to 0.43 and the other increased from 1.12 to 2.45. Compared with the pattern observed for height, LOD scan profiles for diameter and volume showed less temporal change of peaks, suggesting that the genetic control for height growth is probably more unstable than that of diameter. QTLs controlling the phenotype at the time of measurement (ie the final phenotype) showed similar magnitude of effects on that trait's respective increments (or growth rate).

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Thomas, Roger Charles. "Retention of N-15 labelled urea in a radiata pine ecosystem : effect of split applications." Thesis, University of Canterbury. Forestry, 1987. http://hdl.handle.net/10092/7500.

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The efficiency of fertilizer nitrogen uptake and retention within the ecosystem were studied in a 2-year-old radiate pine stand. This was a third rotation site on coastal sand dunes. Application of 90g N/tree (150 kg N/ha), as either Single, 3-split or 9-split dressings, were applied as urea solution, labelled with 2.69 atom % N-15. A control and three seasonal treatments (30 g N/tree) were also included. The trees were in the centre of 7 m² root isolated plots. The experiment ran for a period of 17 months during which time N-15 uptake was monitored by foliar analysis. Steady levels were reached 6 months after the single application. The indicated that soil processes acted on the N-15 pool to achieve an equilibrium with soil-N. The final distribution of fertilizer nitrogen within the ecosystem was determined by a complete tree harvest (including roots) and soil sampling to 90cm. There was a 25% increase in above ground biomass formed in the year after fertilization with 90 g N/tree. The below ground response was more marked, with an 80% increase in fine (<2 mm) roots. Irrespective of the rate, the season of the splitting of the application, the tree’s uptake of fertilizer nitrogen was the same (mean = 21.3%). However, the retention within the soil varied from 40% with a Single application to 70% for the 9-split application. The total ecosystem retention varied from 60% (Single) to 90% (9-Split) excluding volatilization (<2%) and uptake by surrounding trees (<3%). The retention for the seasonal treatments was similar to the split treatments. The was a positive relationship between tree uptake of fertilizer nitrogen and initial sink size. Other major factors determining the range of tree uptakes (15-32%) were leaching and immobilization. The high soil retention of fertilizer nitrogen at the lower application rate, and for split applications, suggests immobilization is a dominant process. Leaching was most prominent for the Single 90 g N application. The extent of this loss may have precluded further uptake by the tree. Although total retention was increased with split applications, there was no immediate benefit to the tree. Given that this additional nitrogen is a very minor proportion of the total; in the soil, the probability of additional; responses seems unlikely. Split applications did not increase tree uptake of nitrogen. Indeed, in the absence of leaching a single application may be utilised more efficiently.

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Slui, Benjamin Thomas. "The effect of plot co-registration error on the strength of regression between LiDAR canopy metrics and total standing volume in a Pinus radiata forest." Thesis, University of Canterbury. School of Forestry, 2014. http://hdl.handle.net/10092/10460.

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Background: The objective of this study was to verify the effect that plot locational errors, termed plot co-registration errors, have on the strength of regression between LiDAR canopy metrics and the measured total standing volume (TSV) of plots in a Pinus radiata forest. Methods: A 737 hectare plantation of mature Pinus radiata located in Northern Hawkes Bay was selected for the study. This forest had been measured in a pre-harvest inventory and had aerial LiDAR assessment. The location of plots was verified using a survey-grade GPS. Least square linear regression models were developed to predict TSV from LiDAR canopy metrics for a sample of 204 plots. The regression strength, accuracy and bias was compared for models developed using either the actual (verified) or the incorrect (intended) locations for these plots. The change to the LiDAR canopy metrics after the plot co-registration errors was also established. Results: The plot co-registration error in the sample ranged from 0.7 m to 70.3 m, with an average linear spatial error of 10.6 m. The plot co-registration errors substantially reduced the strength of regression between LiDAR canopy metrics and TSV, as the model developed from the actual plot locations had an R2 of 44%, while the model developed from the incorrect plot locations had an R2 of 19%. The greatest reductions in model strength occurred when there was less than a 60% overlap between the plots defined by correct and incorrect locations. Higher plot co-registration errors also caused significant changes to the height and density LiDAR canopy metrics that were used in the regression models. The lower percentile elevation LiDAR metrics were more sensitive to plot co- registration errors, compared to higher percentile metrics. Conclusion: Plot co-registration errors have a significant effect on the strength of regressions formed between TSV and LiDAR canopy metrics. This indicates that accurate measurements of plot locations are necessary to fully utilise LiDAR for inventory purposes in forests of Pinus radiata.

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24

Loe, Valerie A. "Management Strategies for Pitch Canker Infected Año Nuevo Stands of Monterey Pine." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/347.

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The future resilience of Pinus radiata D. Don (Monterey pine) is dependent upon the development of a silviculture program inclusive of either preventative or management techniques for the potentially fatal pitch canker disease (Fusarium circinatum Nirenberg and O’Donnell [=F.subglutinans (Wollenw. & Reinking) Nelson et al. f. sp. Pini). As an ecologically and commercially valued species, a myriad of factors threaten the genetic resources of the geographically limited natural range. This study evaluated the effectiveness of uneven-aged forest management for regeneration success in the native, pitch canker infected Año Nuevo stand at Swanton Pacific Ranch in Davenport, California. Seedling survival and growth averages were used to evaluate the impact of the variables of gap size (0.20-hectare, 0.10-hectare, and 0.05-hectare), site-preparation treatment (pile and burn, lop and scatter), and parent tree (13 local seed sources). Pitch canker symptoms were quantified to conclude if there is indeed a range of expressed resistance according to parent tree. Statistical models (i.e. ‘mixed effect’) yielded moderately significant differences in odds of survival between site treatments, with pile and burn plots producing higher survival rates (p=0.066). No significant difference in survival was detected between gap-sizes (p=0.936 and 0.803, 0.05- and 0.10-hectare gaps respectively to 0.20-hectare reference). Significant variation was expressed (estimate=0.1219, SE=0.057) between the 13 parent trees, implicating usefulness in predicting seedling survival. ‘Mixed effect’ models only detected a significant effect from gap-size on growth measures: 0.20-hectare gaps yielded height and diameter measures significantly larger than 0.05-hectare gaps (p=0.027 and 0.0081 respectively). Contingency tables detected significant association between gap-size and number of pitch canker branch symptoms. The range of infection rates produced by the 13 parent trees did not prove significant by analysis. Pile and burn site preparation treatment increases the probability of survival for artificially regenerated seedlings and 0.20-hectare gaps yield significantly higher growth averages over 0.05-hectare gaps.

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25

Mason, Euan G. "Decision-support systems for establishing radiata pine plantations in the central North Island of New Zealand." Thesis, University of Canterbury. Forestry, 1992. http://hdl.handle.net/10092/7205.

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A framework for decision-making relating to establishment of radiata pine plantations was defined, with provision for both numerical models and non-numerical representations of knowledge. Data from Nelder-design experiments were used to investigate the amount of between-tree competition occurring in young radiata pine plantations. Dbhob was found to be unrelated to initial stocking prior to year five. Modelling of basal area/ha growth and yield in a Nelder-design experiment showed that functions used in traditional basal area models under-estimated basal area growth during the two years following the time when mean height was 1.40 m. An adjustment was made to these functions, allowing for allometric assumptions on which growth models are based, which improved models estimates of early basal area/ha growth. Models of young radiata pine survival and size class distribution models were built for crops aged 0 to 5 years in the Central North island region of New Zealand. Data came from site preparation experiments, and the models are sensitive to variations in altitude and site preparation practices. Off-site preparation practices studied, weed control was found to have the largest effect on both initial survival and growth. Mounding improved growth to a lesser extent, and cultivation improved survival of young trees. Fertilisation with nitrogen and phosphorous was found to have a negligible effect on growth and no effect on tree survival. The basal area/ha function incorporated the allometric adjustment developed during the analysis of Nelder-design experiments in a way which resulted in compatible mean height and basal area/ha models. As an illustration of the potential for non-numerical decision-support tools, a knowledge-based computer program was developed to assist forest managers in selecting herbicidal treatments prior to, or during the years following plantation establishment. The system was built using techniques developed for artificial intelligence applications, in a form which allows updating of knowledge relating to weeds, herbicides, surfactants, application methods and treatments, by experts unfamiliar with computer programming. Opportunities for incorporation of these tools into a comprehensive decision-making and control system are discussed.

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Dubey, Manoj Kumar. "Improvements in stability, durability and mechanical properties of radiata pine wood after heat-treatment in a vegetable oil." Thesis, University of Canterbury. School of Forestry, 2010. http://hdl.handle.net/10092/3856.

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Radiata pine is a major plantation grown wood in the Southern hemisphere, but has inferior dimensional stability and low durability compared to other commercial species and the improvement of these features is the focus of this thesis. Specifically this thesis examines the dimensional stability, durability and mechanical properties of radiata pine after heat-treatment (160-210°C) in linseed oil. Changes in colour, micro-structure and chemistry with heat-treatment were studied. To optimise the treatment results, oil heat-treatment of wood was also carried out after thermo-mechanical compression of wood and the effect of the prior thermo-mechanical compression on stability, durability and mechanical properties were examined. The oil heat-treated wood turned uniformly darker in colour. The hydrophobicity (Water Repellence Efficiency-WRE up to 30%), dimensional stability (Ant-Swelling Efficiency-ASE up to 60%) and fungal resistance (up to 36%) were improved with the extent of the changes mainly depending on treatment temperature. However, the mechanical properties of oil heat-treated wood were reduced compared to the untreated control group. Accelerated UV weathering tests have shown that the oil heat-treated wood retained its colour and dimensional stability better than the untreated wood (the control group). The cell wall of treated wood was intact and no distinct structural changes were observed even at the most severe treatment (210°C for 6 hrs).The treatment resulted in changes to the wood chemical constituents, mainly the degradation of hemicelluloses which is believed to be principal reason for alterations in wood properties. A study of the effect of prolong heating on the linseed oil showed an increase in viscosity with heating time which in turn reduced the oil uptake and water repellency of treated wood. However, no significant difference in the colour and dimensional stability of the treated wood was noticed with oil of different heating ages. Oil absorbed by the wood during heat treatment was removed by organic solvent extraction and its contribution to the weight percentage change and moisture related properties were evaluated. The oil uptake percentage, determined by organic solvent extraction, was greater than the weight percentage loss that was deduced to occur during the heat treatment phase, which was attributed to mass losses or thermal degradation of wood constituents. Moisture excluding efficiency decreased after removal of the oil from treated wood, which suggested that the hydrophobicity of treated wood is affected by oil absorbtion. The influence of the post-treatment cooling period on properties of treated wood was studied separately. Oil uptake increased substantially with the post-treatment cooling time which in turn affected the hydrophobicity of treated wood although this effect was less important to dimensional stability. The loss of mechanical properties due to heat-treatment was successfully countered by thermo-mechanical compression of wood prior to the oil heat-treatment. The wood was compressed to 39% of its original thickness without any visible surface checks and cracks. Spring back and compression set recovery in densified wood decreased after oil heat-treatment. This combination treatment also resulted in improved fungal resistance compared to untreated wood. From this research, it is concluded that oil heat-treatment of radiata pine wood can improve its dimensional stability and durability obviating the need to introduce any persistent toxic chemicals. Thermo-mechanical densification of wood prior to oil heat-treatment can countered the loss of mechanical properties due to heat-treatment. The heating oil can be re-used in subsequent treatments and oil uptake can be minimised by limiting the post-treatment cooling time without any significant effect on the dimensional stability of treated wood.

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27

Reivant, Munters Arielle. "The foliar bacterial endophyte community in native Pinus radiata: a role for protection against fungal disease?" Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-234871.

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Pinus radiata is the most planted tree in the southern hemisphere. The planted trees are especially susceptible to pathogens, but even the native population, nowadays limited tomerely five locations, are threatened by diseases caused by arthropods, fungi and dehydration. Endophytes are bacteria or fungi that reside inside healthy plant tissue, and often have a beneficial effect on their hosts. Endophytes can help plants adapt to abiotic stress such as drought and protect them against pathogens and insect pests. Given the roles that endophytes play in host stress responses, it is possible that without studying endophytes we may not fully understand a plant’s response to increased temperatures and climate-induced disease.Using Illumina-sequencing of the 16S rRNA-gene the bacterial endophyte community in 15 trees from three of the remaining native populations were studied. By investigating trees from several sites geographical community differences were discovered. The three overall most dominating bacterial taxa can all be connected with genera known to contain members withanti-fungal properties.

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28

Moreno, Chan Julian. "Moisture content in radiata pine wood : implications for wood quality and water-stress response : a thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in Forestry, School of Forestry, College of Engineering, University of Canterbury /." Thesis, University of Canterbury. School of Forestry, 2007. http://hdl.handle.net/10092/1217.

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This thesis studied the influence of moisture content on the dynamic estimation of stiffness in wood of Pinus radiata D. Don. This is an important non-destructive measure for estimation of stiffness in standing trees, logs and lumber. Moisture content affects both acoustic velocity and density in the fundamental equation of dynamic MOE (DMOE = V²ρ, where V = acoustic velocity and ρ = density). Investigation included measurements with boards in the laboratory considering moisture contents below and above FSP as well as temperatures below and above 0°C. This also included field measurements of trees in contrasting climate sites and over different seasons including a long drought. Methods for measuring green density and moisture content and the patterns of variation of these parameters were also investigated. A secondary component of this thesis explored the wood quality and some mechanisms of tree response to water stress in two contrasting sites in terms or rainfall and water deficits in a region of Australia. The large increases in DMOE for frozen wood above the FSP (4.5 to 6 GPa) will limit the use of DMOE for grading logs in regions with freezing winters. Results from the experiment remeasuring young trees and the upper range of moisture content and temperatures above 0°C from the experiment with boards showed small to moderate variation in DMOE (0.1 to 1 GPa) which calls for further investigation on analytical procedures for adjustment of DMOE. Such procedures should consider that variations in acoustic velocity and density with changes in moisture content are not proportional and that there are counteracting effects between the two parameters. It remains to be investigated whether the typical variation (under normal climate conditions) in sapwood green density observed in our experiments has some implications for the use of DMOE. On the other hand, it is anticipated that the large differences along the stem and among stands in whole-section green density may bias DMOE measurements in logs for resource assessment. This also needs to be investigated. A comparison between acoustic velocity alone and DMOE for resource assessment under different scenarios is recommended. The study in two contrasting climate sites (high-altitude vs. warm-dry) in the Hume region of Forests NSW, Australia, including young (10-11 years) and mature trees (34 36 years) of radiata pine showed distinctive short and long-term responses of trees to cope with the water-limiting environment. In response to long-term water deficits the warm-dry site developed heartwood and thus reduced sapwood earlier and at faster rates than the high-altitude site. The onset of heartwood formation seemed to be triggered by some site threshold for water use as broadly indicated by the sapwood area/ha. The latter was consistently lower for the warm-dry site across the different stands. The warm-dry site also showed increased short-term responses to water stress and these were interpreted as seasonal mechanisms of the trees to cope with the limiting environment. The trees compensated for the lower available moisture and higher transpiration rates by lowering their saturation and disrupting water conduction at some points (cavitation). The inverse trends of cavitation spots and cavitation bands with height in the stem suggested the trees have different strategies to sacrifice conducting xylem depending on the position on the stem. Finally, it is suggested that saturation tended to fall to critical 'safe' levels as a result of water stress and this varied depending on age, site, and position in the stem. Significant decreases in DMOE and basic density were observed for the warm-dry site and were attributed to lower proportions of latewood due to lower rainfall for that site during the period of latewood formation. These showed no obvious association with any of the long-term water-stress traits (sapwood percentage and number of heartwood rings).

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Pinjuv, Guy L. "Hybrid forest modelling of Pinus Radiata D. Don in Canterbury, New Zealand." Thesis, University of Canterbury. New Zealand School of Forestry, 2006. http://hdl.handle.net/10092/1102.

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During this study two models were developed to predict growth of Pinus radiata D.Don plantations in Canterbury, New Zealand. The first, CanSPBL(1.2), is a model for whole rotations of stands owned by Selwyn Plantation Limited in Canterbury. The second model, CanSPBL(water) is a hybrid growth model for the Selwyn estate in Canterbury that incorporates an index of root zone water balance over the simulation period. An existing stand growth and yield model CanSPBL was examined using a validation dataset of PSP measurements that were not used in model fitting. Projection bias was shown for mean top height, basal area per hectare, and residual stand stocking particularly for stands at elevations exceeding 450 metres. The new model, CanSPBL(1.2) showed an increase in precision of 4 - 46% over CanSPBL(1.0) at a stand level. The components of the stand model include mean top height, basal area per hectare, stems per hectare, and diameter distribution. The mortality model was made in conjunction with managers at CanSPBL to exclude catastrophic mortality events from model projections. Data used for model fitting was filtered using a mortality index based on the -3/2 power law. An examination of this model with an independent dataset showed little apparent bias. The new model, CanSPBL(water) was developed to include an index of water balance over the simulation period. Water balance estimates were made using a sub model for root zone water balance included in the hybrid physiological model 3-PG (Landsberg and Waring, 1997). The new model showed an increase in precision of 1 - 4% over CanSPBL(1.2) at a stand level (with the exception of the model for maximum diameter which showed a decrease in precision of 0.78%) using climatic inputs that included yearly variation. However the model showed increases of precision from 0.5 to 8% (with the exception of maximum diameter again, showing a decrease in precision of 0.13%) using long term monthly average climatic inputs. The components of the stand model also include mean top height, basal area per hectare, stems per hectare, and diameter distribution. The mortality model was also fitted with a data set filtered using a mortality severity index based on the -3/2 power law to exclude catastrophic mortality events. An examination of this model with an independent dataset showed little apparent bias. Two models to predict a one sided canopy leaf area index (LAI) of radiata pine stands in the Canterbury Plains of New Zealand were also developed. The models were fitted using non-linear least squares regression of LAI estimates against stem measurements and stand characteristics. LAI estimates were derived from digital analysis of fisheye lens photography. The models were kept simple to avoid computational circularity for physiological modelling applications. This study included an objective comparison and validation of a range of model types. The models CANTY (Goulding, 1995), CanSPBL(1.2) (Pinjuv, 2005), CanSPBL-water (Pinjuv, 2005), and 3-PG (Landsberg and Waring, 1997) were compared and validated with the main criteria for comparison being each model s ability to match actual historical measurements of forest growth in an independent data set. Overall, the models CanSPBL(water), and CanSPBL(1.2) performed the best in terms of basal area and mean top height prediction. Both models CanSPBL(water), and CanSPBL(1.2) showed a slightly worse fit in predictions of stocking than did the model CANTY. The hybrid model 3PG showed a better fit for the prediction of basal area than the statistically based model CANTY, but showed a worse fit for the prediction of final stocking than all other models. In terms of distribution of residuals, CanSPBL(1.2) had overall the lowest skewness, kurtosis, and all model parameters tested significant for normality. 3PG performed the worst on average, in terms of the distribution of residuals, and all models tested positively for the normality of residual distribution.

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Xu, Hongyuan. "Modelling photosynthetic CO₂ fixation in radiata pine clones with contrasting crown characteristics at age five at Dalethorpe, Canterbury, New Zealand." Thesis, University of Canterbury. Forestry, 2000. http://hdl.handle.net/10092/7502.

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A program was developed to simulate the individual tree photosynthesis of ten Pinus radiata D. Don clones at age 5, and a comparison was made between the clones at a given condition to estimate photosynthesis from leaf level to tree level. The model linked the sub-models of leaf level photosynthesis, crown shape, foliage area, foliage area density distribution, and light penetration probability within tree crowns together to estimate total net photosynthesis on individual tree level. This study was carried out at a radiata pine clonal experiment at the same site with the same treatment located at Dalethorpe, Canterbury, New Zealand. At leaf level, seasonal photosynthetic responses to light and temperature curves of 1-, 2- and 3-year-old needles were measured under controlled environmental conditions in the field. Needle net photosynthetic rates did not show statistically significant differences between clones. Net photosynthesis decreased with leaf age but increased with temperature (5°C - 20°C). Comparing the maximum photosynthetic rates under the same measurement conditions, there were no statistically significant differences among the ten clones or according to crown position (crown level and aspect i.e. north-, south-, east-, and west-facing). In describing crown shape, a simple crown shape was developed. The model can be used to calculate crown radii, the maximum crown radius, the crown base radius, crown volume and vertical volume distribution of different needle age classes. Above-ground biomass and needle surface area were estimated. The total above-ground biomass and its allocation showed significantly difference among growth difference clones. Tree height was poorly correlated with total biomass production, but DBH was strong correlated with needle, branch and total biomass. The vertical distributions of needle biomass, needle surface area, and needle surface area density were studied according to age class. In estimating light penetration within tree crowns, a simple light penetration program was developed. The program was based on data from crown architecture analysis, geometrical analysis of the light penetration distance within crowns and models of crown shapes. The program can be used to estimate the probability of direct light penetration at any given sun zenith angle and diffuse light penetration at any given direction with azimuth angle ∠θ and elevation angle ∠β. With the developed individual tree net photosynthesis process model, the influence of foliage mass, crown shape, light penetration probability, incoming sun zenith angle, crown light extinction coefficient k-value and needle photosynthetic capacity on total tree net photosynthesis was studied. Simulation results indicated that foliage mass was an important factor influencing total tree photosynthetic rate. However, other factors, such as crown shape and needle photosynthetic capacity, all influenced the variation of total tree photosynthetic rates in various environment conditions.

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Kolokolova, Olga. "Biomass Pyrolysis and Optimisation for Bio-bitumen." Thesis, University of Canterbury. Chemical and Process Engineering, 2013. http://hdl.handle.net/10092/8822.

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Biomass waste has been recognised as a promising, renewable source for future transport fuels. With 1.7 million hectares of pine plantation forests and 12 million cubic meters of annual residue produced by sawmills and the pulp and paper industries, New Zealand presents a prime location where utilisation of these resources can take the next step towards creating a more environmentally friendly future. In this research, the process of fast pyrolysis was investigated using a laboratoryscale, nitrogen-blown fluidised bed pyrolyser at CRL Energy. This equipment can process 1–1.5 kg/h of woody biomass in a temperature range of 450–550°C. The purpose of this rig was to determine the impact of various processing parameters on bio-oil yields. Next, the pyrolysis liquids (bio-oil and tar) were processed downstream into bio-bitumen. Pyrolysis experiments were carried out on Pinus Radiata and Eucalyptus Nitens residue sawdust from sawmills and bark feedstock. The properties of the collected products, including pyrolysis liquids (bio-oil and tar), gas and solid bio-chars, were measured under different operational conditions. Further analysis was also performed to determine pH, volatile content, chemical composition and calorific values of the products. The ultimate goal for this project was to develop a feasible, advanced fast-pyrolysis system for a bio-bitumen production plant using various biomass feedstocks. Additionally, a design for a bio-bitumen production plant was developed, and techno-economic analysis was conducted on a number of plant production yield cases and bio-bitumen manufacture ratios.

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Shi, Shengjing. "Influence of root exudates on soil microbial diversity and activity." Lincoln University, 2009. http://hdl.handle.net/10182/1549.

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Interactions between plant roots and soil microorganisms in the rhizosphere are critical for plant growth. However, understanding of precisely how root exudates influence the diversity and activity of rhizosphere microorganisms is limited. The main objective of this study was to investigate the effect of radiata pine (Pinus radiata) root exudates on rhizosphere soil microbial communities, with an emphasis on the role of low molecular weight organic anions. The study involved the development and validation of new methods for investigating rhizosphere processes in a purpose-built facility. This included development of an in situ sampling technique using an anion exchange membrane strip to collect a range of organic anions exuded from radiata pine roots grown in large-scale rhizotrons. These included tartarate, quinate, formate, malate, malonate, shikimate, lactate, acetate, maleate, citrate, succinate and fumarate. Soil microbial activity and diversity were determined using dehydrogenase activity and denaturing gradient gel electrophoresis. Links between organic anions in root exudates and rhizosphere soil microbial community structures were investigated by comparing wild type and genetically modified radiata pine trees which were grown in rhizotrons for 10 months. As expected, there was considerable temporal and spatial variability in the amounts and composition of organic anions collected, and there were no consistent or significant differences determined between the two tree lines. Significant differences in rhizosphere microbial communities were detected between wild type and genetically modified pine trees; however, they were inconsistent throughout the experiment. The shifts in microbial communities could have been related to changes in exudate production and composition. Based on results from the main rhizotron experiment, a microcosm study was carried out to investigate the influence of selected pine root exudate sugars (glucose, sucrose and fructose) and organic anions (quinate, lactate and maleate) on soil microbial activity and diversity. Soil microbial activity increased up to 3-fold in all of the sugar and organic anion treatments compared to the control, except for a mixture of sugars and maleate where it decreased. The corresponding impacts on soil microbial diversity were assessed using denaturing gradient gel electrophoresis and 16S rRNA phylochips. Addition of the exudate compounds had a dramatic impact on the composition and diversity of the soil microbial community. A large number of bacterial taxa (88 to 1043) responded positively to the presence of exudate compounds, although some taxa (12 to 24) responded negatively. Organic anions had a greater impact on microbial communities than sugars, which indicated that they may have important roles in rhizosphere ecology of radiata pine. In addition, a diverse range of potentially beneficial bacterial taxa were detected in soil amended with organic anions, indicating specific regulation of rhizosphere microbial communities by root exudates. This project highlighted the considerable challenges and difficulties involved in detailed investigation of in situ rhizosphere processes. Nonetheless, the findings of this study represent a significant contribution to advancing understanding of relationships between root exudates and soil microbial diversity, which will be further enhanced by refinement and application of the specific methodologies and techniques developed.

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Fries, Megan L. "Relationships between Rooting Restrictions, Radial Growth, and Drought Stress with White Pine (Pinus strobus) Decline in Southern Maine." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/FriesML2002.pdf.

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Barrios, Rodríguez Andrés. "Determinación del diámetro del cilindro defectuoso en trozas podadasde pino radiata (Pinus radiata D.Don), mediante atenuación de radiación gamma." Tesis, Universidad de Chile, 2004. http://www.repositorio.uchile.cl/handle/2250/105025.

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Camacho, Focacci Felipe Ignacio. "Productividad primaria bruta y neta en plantaciones de Pinus radiata D. Don en la Región del Bío Bío, Chile." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/150827.

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Memoria para optar al Título Profesional de Ingeniero Forestal
Se realizaron inventarios forestales mensuales y mediciones fisiológicas trimestrales en plantaciones de Pinus radiata D. Don en la Región del Bío Bío en las cuatro principales zonas de crecimiento para esta especie (IV, V, VI y VII) durante 24 meses entre Agosto de 2010 y Agosto de 2012. Los predios donde se ubicaron los ensayos fueron Lomas Coloradas en la Comuna de San Pedro de la Paz, Nacimiento en la Comuna de Nacimiento, Santa Bárbara en la Comuna de Santa Bárbara y Tapihue en la Comuna de Cabrero. Para cada sitio se consideraron tres clases de edad (0-7, 7-14 y 14+ años). En cada uno de las 12 instancias de Zona-Edad, se procedió a instalar un conglomerado de 3 parcelas permanentes de 1.000 m2, totalizando 36 parcelas. Estos predios y rodales se ubicaron a menos de 10 km de las estaciones meteorológicas de Escuadrón (Lomas Coloradas), Pichún (Nacimiento), Santa Bárbara (Santa Bárbara) y Trilahue (Tapihue), pertenecientes a Forestal Mininco S.A.

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Rojas, Retamal Emilio Arturo. "Índice de área foliar en plantaciones de Pinus radiata D. Don en la la Región del Bío Bío, Chile." Tesis, Universidad de Chile, 2014. http://repositorio.uchile.cl/handle/2250/151645.

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Memoria para optar al Título Profesional de Ingeniero Forestal
Se midió mensualmente el índice de área foliar en plantaciones de Pinus radiata D. Don en la región del Bío Bío en las cuatro principales zonas de crecimiento para esta especie (IV, V, VI y VII) durante 24 meses entre Octubre de 2010 y Octubre de 2012. Los predios donde se ubicaron los ensayos fueron San Pedro de la Paz (predio Lomas Coloradas), Nacimiento (predio Nacimiento), Santa Bárbara (predio Santa Bárbara) y Cabrero (predio Tapihue). Para cada sitio se consideraron tres clases de edad ([0-7), [7-14) y [14+)). En cada uno de los 12 puntos de Zona-Edad, se procedió a instalar un conglomerado de 3 parcelas permanentes de 1.000 m2, totalizando 36 parcelas, entre los meses de Agosto y Septiembre de 2010. Estos predios y rodales se ubican a menos de 10 km de las estaciones meteorológicas de Escuadrón (Lomas Coloradas), Pichún (Nacimiento), Santa Bárbara (Santa Bárbara) y Trilahue (Tapihue) que mantiene Forestal Mininco S.A. La edad se correlacionó positivamente con el índice de área foliar (L) como era de esperar. Además se aprecia que el L crece fuertemente desde la clase de edad [0-7) a la [7-14), comparado con el crecimiento entre la clase de edad [7-14) a [14+). Lo anterior implica que el mayor crecimiento en área foliar se genera antes de los 14 años. Además a lo largo de los 24 meses se observa que el L aumenta fuertemente en la clase de edad [0-7), en menor cuantía en la clase de edad [7-14), y muestra un crecimiento prácticamente imperceptible en la clase [14+) años.

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Sokol, Kerry Ann. "Implications of Longterm Diameter-Limit Harvesting: Effects on Radial Growth of Red Spruce (Picea rubens) and Genetic Diversity of White Pine (Pinus strobus)." Fogler Library, University of Maine, 2001. http://www.library.umaine.edu/theses/pdf/SokolKA2001.pdf.

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38

Ramírez, Farfán Álvaro Felipe. "Comportamiento al biodeterioro de madera de pino radiata (Pinus radiata D.Don) tratado con cobre-azol (CA-B), contra hongos de pudrición y termita subterránea." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/151377.

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Memoria para optar al Título Profesional de Ingeniero Forestal
La madera de pino radiata, principal recurso maderero del país, es de baja durabilidad. Hongos e insectos, entre otros factores de su deterioro, son usualmente los más relevantes. Del grupo de los insectos, en particular la termita subterránea “Reticulitermes flavipes”, representa hoy la mayor preocupación, por su agresividad y avance permanente en áreas pobladas del país. El arseniato de cobre cromado (CCA) fue, por décadas, el preservante más utilizado en todo el mundo para proteger la madera, sin embargo, preocupaciones medioambientales, hace más de diez años, dieron paso a un cambio hacia otros productos. El uso de cobreazoles (CA) y en particular el de tipo B, junto con cobreazol micronizado, han sido los cambios más importantes desde entonces a nivel mundial. Su incorporación al mercado local, sin embargo, ha sido muy lenta, básicamente por costo y por no existir un marco legal que regule el uso de madera tratada con CCA. Sobre la base de los requisitos exigidos por la Australian Standard®, AS 1604.1-2012, para madera tratada con CA-B, el objetivo del estudio fue evaluar el comportamiento de madera de Pino radiata tratada con CA-B, a retenciones menores a las exigidas por la Norma Chilena, frente al ataque de hongos de pudrición y termita subterránea. Los métodos empleados fueron; “Standard Test Method for Wood Preservatives by Laboratory Soil-Block Cultures”, descrito en la ASTM Designation: D1413 − 07ɛ1 y la Norma Chilena NCh 3060.Of 2007, para el estudio con hongos y termita subterránea respectivamente. En el estudio con Lentinus lipideus, todos los grupos de retención presentaron efecto positivo en el control del hongo y diferencias estadísticamente significativas respecto a las probetas testigo. En el caso de Coriolus versicolor, solo los grupos de retención 1,4 y 1,8 kg/m3 se diferenciaron estadísticamente del testigo en el control del hongo. En el estudio contra termita subterránea, la retención necesaria de CA-B para el control de Reticulermes flavipes se ubicó entre las retenciones 1,4 y 1,8 kg/m3 (concordante con la Norma NCh 819:2012). Una retención menor en pino radiata tratado con CA-B, no pudo ser validada para el control de termita subterránea, Reticulermes flavipes.

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39

Escobar, Cuadros Martín A. H. "Efecto Selectivo de las Plantaciones de Pino Radiata (Pinus radiata D. Don) Sobre la Comunidad de Artrópodos de Follaje de Nothofagus, en el Bosque Maulino de la Región Central de Chile." Tesis, Universidad de Chile, 2008. http://www.repositorio.uchile.cl/handle/2250/105012.

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Memoria para optar al Título Profesional de Ingeniero Forestal
Uno de los mayores efectos de la actividad antrópica en Chile central ha sido la transformación de vegetación natural en plantaciones forestales de Pinus radiata. Sin embargo, el conocimiento de la comunidad de artrópodos en este ecosistema artificial y su interacción con los remanentes de bosque nativo es todavía escaso. El objetivo de este estudio fue determinar y comparar la comunidad de artrópodos del follaje en plantaciones de P. radiata y bosques de Nothofagus, en la región del Bosque Maulino de Chile central. Se analizaron artrópodos colectados en el follaje de plantaciones de pino y bosques de Nothofagus glauca y N. dombeyi, y sus respectivos sotobosques. Se establecieron parámetros comunitarios y análisis de similitud y exploratorios entre atributos del sitio y las características de la comunidad de artrópodos. Además, se evalúo el efecto selectivo de las plantaciones sobre distintos gremios tróficos de este grupo. La comunidad de artrópodos del follaje en plantaciones de P. radiata presentó menores valores de riqueza, diversidad y abundancia, a nivel de unidad de muestreo que bosques de Nothofagus, pero las fluctuaciones naturales de estos parámetros y las características particulares de los follajes comparados hacen que las diferencias se reduzcan al comparar abundancias totales. La abundancia de artrópodos en el sotobosque de las plantaciones tendría un efecto importante en la artropofauna del follaje en el dosel de P. radiata, aunque este efecto es grupo-específico. Las fluctuaciones estacionales de bosques de N. glauca y plantaciones de P. radiata sugieren la existencia de movimientos de la artropofauna del follaje entre los doseles superiores de estas formaciones. Los análisis por gremios tróficos indicarían cierto efecto selectivo de las plantaciones de P. radiata en los artrópodos del follaje, aunque es probable que la artropofauna presente en estos ecosistemas productivos corresponda a una comunidad aún en proceso de formación, limitada por el manejo asociado a estas plantaciones (rotación y cosecha). Finalmente, la presencia de una comunidad de artrópodos en el follaje de las plantaciones de P. radiata, permitirían una continuidad de hábitat para muchas especies de artrópodos de bosque, que facilitaría el mantenimiento de procesos ecológicos a nivel de paisaje

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40

Despain, Del Westover. "Radial Growth Relationships in Utah Juniper (Juniperus Osteosperma) and Pinyon Pine (Pinus Edulis)." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184705.

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The assumption that each latewood ring in trees represents one year of growth was tested for Utah juniper (Juniperus osteosperma) and pinyon pine (Pinus edulis). Ring characteristics and growth rates were evaluated for 72 years of growth following scars of consistent date on all trees sampled. Errors in age and growth rate estimates based on ring counts were evaluated. Potential variation among observers was accounted for. Average error in ring counts was lowest when rings were counted on the fastest-growing portions of each cross-section. Errors for more than 40% of the junipers exceeded 10 percent with about half of the trees with more rings and half with less rings than actual years. Pinyons rarely had more rings than years and only 5% of the trees were missing more than 10% of the 72 annual rings. Percentage errors in growth rate estimates based on ring counts were similar to ring count errors for both species. Assigning junipers to age classes based on ring counts also can lead to error in assumed ages of trees. Assuming that ring count error for each tree for the 72 year period studied approximates potential error over the life of each tree, more than half of junipers older than 250 years would be assigned to the wrong age class when using 50 year age classes. Number of rings in junipers was highly correlated with growth rate. Competition from surrounding trees explained as much as 53% and 40% of the variation in growth rates of junipers and pinyons respectively. Relating growth rates and ring counts to ordinations of stand, site and soil characteristics indicated that trees with relatively fast growth rates or trees with the most rings tended to occur on gentle, north to northeast aspects with relatively better- developed soils. However, stand competition often had an overriding influence on growth. Presence of Koelaria pyramidata in the understory was generally an indicator of relatively favorable growing conditions for junipers. Results suggest the need for more caution in the use of ring counts for estimating ages or growth rates of Utah junipers and pinyons than has generally been used in the past, especially when drawing conclusions about specific individuals.

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41

Beauchamp, Kate. "Biology of heartwood formation in Sitka spruce and Scots pine." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5788.

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Heartwood is the dead, inner layers of wood in the tree which no longer transport water. It is usually dark in colour and has increased decay-resistance compared to the sapwood. Heartwood forms in the transition zone when the ray cells die and deposit chemical extractives in the surrounding xylem. These chemicals convey natural durability which is of value to the forest and timber industry. Despite its value the formation of heartwood is poorly understood. The objective of this PhD is to improve our understanding of heartwood formation in Sitka spruce and Scots pine, the most widely planted species in Britain. Separating heartwood and sapwood at the sawmill can increase timber value due to differences in wood properties. The amount of heartwood varies both with height within, and between trees. Empirical models were developed to describe heartwood and sapwood distribution by diameter, area and ring number 1) within any wood disc 2) with height in the standing tree using taper functions, and 3) its variation between trees. Models will be incorporated into wood quality models to optimise heartwood utilisation. According to pipe theory a certain area of sapwood sustains a volume of canopy, with redundant sapwood converted to heartwood. Sap flux was examined across the sapwood and transition zone in Sitka spruce to understand water transport in relation to heartwood formation and identify seasonal change in transport in the transition zone. Results suggest that the transition zone ceases water transport around dormancy and the amount of heartwood formed may be driven by new wood formation, maintaining sapwood depth. Heartwood formation is a seasonal process, however this has not been confirmed in Sitka spruce or Scots pine, or under UK climatic conditions. Seasonal variation in carbon dioxide and ethylene production by the transition zone were measured to identify the time of heartwood formation, which was late summer through dormancy, consistent with published literature. The role of ethylene in heartwood formation is confirmed. Heartwood formation is an active developmental process, a form of programmed cell death, and as such must be carefully regulated temporally and spatially. Regulation by phytohormones has been proposed but not confirmed. Screening for a broad range of phytohormones during the proposed season of heartwood formation identified an increase in abscisic acid and a decrease in auxin concentration in the transition zone. Abscisic acid, auxin and ethylene also regulate xylogenesis, therefore the same signals that initiate cambial dormancy may also provide the temporal regulation of heartwood formation. The results of this PhD will optimise the use of heartwood in Sitka spruce and Scots pine in the UK and contribute towards selective tree breeding for increased heartwood volume worldwide.

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42

Díaz, Ortega Daniela. "Resignificación de la madera de pino radiata : línea de muebles de asiento en madera laminada." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/152347.

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43

González, Retamal Marcelo N. "Bienestar habitacional y eficiencia energética de viviendas sociales industrializadas estructuradas con madera de pino radiata." Tesis, Universidad de Chile, 2008. http://repositorio.uchile.cl/handle/2250/151542.

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Memoria para optar al Titulo Profesional de Ingeniero de la Madera
Esta memoria evaluó el bienestar habitacional y eficiencia energética de un conjunto de viviendas sociales construidas el año 2003 en la comuna de Buín, Región Metropolitana. Estas viviendas fueron construidas utilizando un sistema de construcción modular industrializado (SCMI), siendo el primer proyecto de su tipo en nuestro país. El bienestar habitacional que entrega este tipo de vivienda después de cuatro años de residencia y la eficiencia energética en comparación con una vivienda social de albañilería de ladrillo fueron los puntos centrales de este estudio. El bienestar habitacional se evaluó a través de la percepción de los moradores, a través de la aplicación de una encuesta en una muestra aleatoria del 20% de las viviendas, donde los jefes de hogar encuestados manifestaron sus reacciones frente a un conjunto de preguntas utilizando un escalamiento tipo Likert. Se comparó la eficiencia energética de la vivienda social industrializada de madera con una vivienda alternativa de ladrillo de similares características, mediante cálculos térmicos basados en la normativa nacional existente, y ampliando el análisis a diferentes localidades del país.

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44

Biondi, Franco 1960. "Influence of Gambel oak on radial growth of southwestern ponderosa pine : a dendrochronological study." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/191955.

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Gambel oak influence on diameter increment of young-growth ponderosa pines was evaluated by intensively sampling three pine-oak stands on the Beaver Creek Watershed in north-central Arizona. Sampled stands had homogeneous climate, topography, soil parent material, vegetation structure and soil type. Increment cores were collected from five dominant pines on 34 randomly selected study plots. As revealed by dendrochronological techniques, radial growth of sampled pines had fluctuated around a relatively constant level during the last 50 years (1936-85). Differences in this level among stands were related to differences in competition, oak presence, pine age and site index. Pine diameter growth increased with increasing Gambel oak presence and with decreasing intraspecific competition.

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45

Rist, Stephen George. "Legacies of forest management and fire in mixed-pine forest ecosystems of the Seney National Wildlife Refuge, eastern Upper Michigan." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1218566132.

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McCarthy, James. "The Role of Bark Beetles as Vectors in the Colonisation of Windthrown Timber by Fungi." Thesis, University of Canterbury. Biological Sciences, 2011. http://hdl.handle.net/10092/6263.

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The increasing frequency and severity of windthrow events affecting the forestry industry in New Zealand have raised important management issues surrounding the rate of colonisation of fallen trees by sapstain fungi and the time available for salvage harvesting before sapstain degradation limits potential economic returns. These fungi are known to be spread by a multitude of factors including wind, rain splash, harvesting processes and insect vectoring. Apart from the ecological interest in these interactions between fungi, plants and insects, sapstain fungi are also economically important because their hyphae discolour the sapwood and reduce the overall quality of the timber. The amount of time available to salvage harvest damaged trees is unknown, especially on seasonal and regional scales. Manipulative experiments were established in Pinus radiata forests to examine this seasonal and regional variation in sapstain attack following windthrow, and to investigate the importance of bark beetles as vectors of sapstain fungi. A range of methods were implemented to assess the role of bark beetles as vectors and to ascertain which sapstain fungi are associated with them. Experimental billet logs were caged to exclude beetles and subsequently analyse fungal attack in comparison with identical logs left exposed to beetles. In addition, individual beetles were sampled directly to determine whether they carried spores of particular fungal species and to assess the degree of association in vector-fungal dynamics. Finally, a novel application of DNA melt peak analysis was developed to investigate variation among the fungal communities associated with beetles potentially involved in vectoring sapstain spores. The moisture content of fallen trees was found to be the main factor regulating sapstain development, and when moisture content drops below 100% (on dry weight basis) sapstain fungi grew rapidly. The speed at which this level drops depends on the season, with much faster drying occurring in the warmer months of spring and summer. As a result, trees that fell in the previous winter or autumn did not develop significant sapstain levels until temperatures rose in the following summer, suggesting that storm-damaged trees that fall in winter can be left safely until just before the next summer before they are no longer suitable for salvage harvest. In New Zealand, the bark beetle species acting as vectors of sapstain fungi are not behaviourally adapted to colonisation of logs that are not in contact with the ground. Following windthrow events in pine forests, trees generally lie with their stems suspended above the level of the ground by their branches. As a result, under these circumstances, beetle colonisation of windthrown timber was low, and bark beetles were not a significant vector of stain. The caged and un-caged experimental log billets, however, were in contact with the ground, resulting in colonisation of the un-caged logs. In this case, bark beetles did play an important role in contributing to sapstain intensity, and the stain distribution within the logs mirrored that of the stain distribution. However, this effect may be due to the provision of access points for wind- or water-borne spores of the non-insect vectored stain fungus Diplodia pinea, or to the spread of hyphae through the tunnelling and feeding activities of beetles within the tree, rather than by bark beetles acting as vectors of spores. Bark beetles were confirmed as sapstain vectors with the isolation of seven different ophiostomatoid stain fungi from them, five of which were also found in wood. Finally, the development of a laboratory based, rapid species identification method was developed to identify fungal DNA. Melt peak analysis allowed the species-specific DNA melt temperatures to be compared with the melt temperatures of known species to be able to rapidly, and cheaply, identify an unknown species. Bark beetles are vectors of sapstain fungi in P. radiata forests, however the bark beetle species naturalised in New Zealand prefer to colonise wood when it is in contact with the ground. Following windthrow, trees are generally not attacked by beetles as they are held from the ground by their branches, leaving them to be stained predominantly be wind and rain dispersed stain fungus D. pinea. Stain did not occur until the moisture content of fallen trees dropped below 100%, which only happens in the warm months of summer and spring. In New Zealand, there are interactions between trees and bark beetles, and bark beetles with fungal pathogens from all around the globe resulting in a unique novel assemblage of species together for the first time. Understanding the dynamics of these species in their novel environment is crucial to effectively responding to potential pest threats.

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Riveros, Pérez Carla Victoria. "Efecto del cambio climático en el crecimiento y productividad de Pinus radiata en Chile : análisis utilizando modelos 3-PG y precis." Tesis, Universidad de Chile, 2010. http://repositorio.uchile.cl/handle/2250/151412.

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Memoria para optar al título profesional de Ingeniera en Recursos Naturales Renovables
El Cambio Climático en Chile advierte un futuro calentamiento del país y una disminución de las precipitaciones en la zona centro-sur (~35°-40°S). Dadas estas proyecciones, esta tesis tiene por objetivo evaluar estos efectos sobre el crecimiento y productividad de Pinus radiata, que es un sector productivo importante en la zona afectada, utilizando simulaciones de clima futuro de PRECIS en el modelo 3-PG. PRECIS es un modelo climático regional para el cual existen tres simulaciones: clima actual (periodo 1961-1990), y dos proyecciones del clima futuro para el periodo 2071-2100: uno moderado de emisiones B2 y severo de emisiones A2. El modelo 3-PG simula el crecimiento de los árboles como función de procesos fisiológicos, condiciones meteorológicas y de sitio en un período determinado. La zona de estudio abarca la región administrativa del Maule hasta la de Los Ríos (34.5°S-41°S). El modelo PRECIS fue primero evaluado contra estaciones de observación en el área de estudio, para verificar si el modelo es capaz de reproducir la variabilidad temporal y espacial observada de este clima (precipitación y temperatura). En general PRECIS simula correctamente el ciclo anual de estas variables, siendo el mayor sesgo una sobre-estimación de la precipitación a grandes altitudes y sobre la cordillera de Los Andes. Las variables de PRECIS fueron entonces usadas para correr 3-PG para las condiciones climáticas presentes como las dos proyecciones futuras.

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Pérez, Pérez Mauricio Francisco. "Efecto de la estructura de plantaciones de Pinus radiata D. Don sobre su calidad como hábitat para aves en constitución." Tesis, Universidad de Chile, 2004. http://www.repositorio.uchile.cl/handle/2250/105037.

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Reyes, Vergara Esteban Eduardo. "Proposición de procedimiento experimental normativo para estimar la velocidad de carbonización de la madera laminada encolada de pino radiata." Tesis, Universidad de Chile, 2015. http://repositorio.uchile.cl/handle/2250/137068.

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Ingeniero Civil
Siendo Chile un país aventajado en la obtención y por ende producción de piezas de madera con fines constructivos y estructurales, llama la atención que se encuentre poca información normativa referente a su comportamiento frente al fuego. Si bien existe estandarización de ensayos para componentes que incorporan este material, no la hay en lo referente a la determinación de la velocidad de penetración del proceso de carbonización hacia el interior de las piezas de madera desde la o las caras expuestas a fuentes de calor importantes. El diseño de elementos de madera con resistencia al fuego se realiza a partir de datos y normativas extranjeras, las que en muchos casos responden a las propiedades de los materiales que se disponen en la región correspondiente. El objetivo de este trabajo de título es proponer una secuencia coherente de procedimientos de carácter normativo que permitan determinar la velocidad de carbonización en elementos de madera laminada encolada, específicamente de pino radiata, dada su importancia a nivel forestal y comercial en nuestro país. El método planteado se realiza sobre la base de antecedentes y estructuraciones de ensayos obtenidos de una revisión de bibliografía internacional, tratando de asemejar algunas de las condiciones en que se efectúan y empleando la tecnología disponible en nuestro medio para su cometido. Los procedimientos aplicados se han calibrado por medio de ensayos exploratorios, aplicándose correcciones cuando ha parecido pertinente, y han permitido estimar valores de las tasas de carbonización que podrían utilizarse en los métodos analíticos de diseño y verificación al fuego de piezas de madera laminada encolada de Pino radiata.

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50

Laws, Nathan. "A Parabolic Equation Analysis of the Underwater Noise Radiated by Impact Pile Driving." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1083.

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Impact pile driving can produce extremely high underwater sound levels, which are of increasing environmental concern due to their deleterious effects on marine wildlife. Prediction of underwater sound levels is important to the assessment and mitigation of the environmental impacts caused by pile driving. Current prediction methods are limited and do not account for the dynamic pile driving source, inhomogeneities in bathymetry and sediment, or physics-based sound wave propagation. In this thesis, a computational model is presented that analyzes and predicts the underwater noise radiated by pile driving and is suitable for shallow, inhomogeneous environments and long propagation ranges. The computational model uses dynamic source models from recent developments in the technical literature. Pile source models are coupled to a broadband application of the range-dependent acoustic model (RAMPE), a standard parabolic equation (PE) propagation code capable of modeling wave propagation through complex, range dependent environments. Simulation results are shown to be in good agreement with several observations of pile driving operations in the Columbia River between Portland, Oregon and Vancouver, Washington. The model is further applied to extend sound level predictions over the entire river and study the effects of sediment and bathymetry on the underwater sound levels present in the environment.

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Dissertations / Theses on the topic 'Radiata pine'

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