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Thesis (Ph. D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1999. / Copies of author's previously published articles inserted. Includes bibliographical references (leaves 122-137).

Call number: LD2668 .T4 1961 B79

Copies of author's previously published articles inserted. / Bibliography: leaves 122-137. / xiv, 158 leaves, [16] leaves of plates : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / 18 species of Eucalyptus were subjected to trials to investigate their suitability for floriculture and the effect of pruning for cut flower production. Post harvest trials were conducted to assess the vase life of cut stems, and the effect of pulsing and simulated transportation on vase life. Species of Eucalyptus were also studied for changes in wax morphology of juvenile foliage with leaf age and for variation in amount and composition of leaf epicuticular wax. Molecular markers were discovered which may facilitate the management of E. gunnii breeding and selection for the cut foliage industry, by providing an initial screen for glaucousness. 12 species were recommened for the cut foliage industry. / Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1999

Copies of author's previously published articles inserted. Bibliography: leaves 122-137. 18 species of Eucalyptus were subjected to trials to investigate their suitability for floriculture and the effect of pruning for cut flower production. Post harvest trials were conducted to assess the vase life of cut stems, and the effect of pulsing and simulated transportation on vase life. Species of Eucalyptus were also studied for changes in wax morphology of juvenile foliage with leaf age and for variation in amount and composition of leaf epicuticular wax. Molecular markers were discovered which may facilitate the management of E. gunnii breeding and selection for the cut foliage industry, by providing an initial screen for glaucousness. 12 species were recommened for the cut foliage industry.

Copies of author's previously published articles inserted. / Bibliography: leaves 122-137. / xiv, 158 leaves, [16] leaves of plates : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / 18 species of Eucalyptus were subjected to trials to investigate their suitability for floriculture and the effect of pruning for cut flower production. Post harvest trials were conducted to assess the vase life of cut stems, and the effect of pulsing and simulated transportation on vase life. Species of Eucalyptus were also studied for changes in wax morphology of juvenile foliage with leaf age and for variation in amount and composition of leaf epicuticular wax. Molecular markers were discovered which may facilitate the management of E. gunnii breeding and selection for the cut foliage industry, by providing an initial screen for glaucousness. 12 species were recommened for the cut foliage industry. / Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1999

The study consisted of two parts: following the fade rates of killed field-grown Virginia pine (<u>Pinus virginiana</u> Mill.); and to study the effects of different stresses on seedlings. Foliage fade rates of killed field-grown Virginia pine varied with the time of the year the tree was killed. Little variation in fade rates was found between years. Foliage of seedlings grown under stress due to: girdling; sevpring; defoliating; and drought, were studied by paper chromntographv, cross sectioning, and photography. The four pigments found appeared to decline proportionately as the foliage went from green to red. An error in technique resulted in uninterpretable needle cross sections. Photography using black and white, black and white infrared, color, and color infrared films gave no previsual detection of stress. / Master of Science

Foliage is very common feature in the habitats of echolocation bats and thus its echoes constitute the major input of bats' sensory systems. Acquiring useful information from vegetation echoes facilitates the bats significantly in the navigation and foraging behaviors. To better understand the foliage echoes, in this dissertation, a computer model was constructed to simulate foliage echoes with following simplifications: approximating leaves as circular disks, leaving out shading effects between leaves, and distributing leaves uniformly in the space. Then one tree can be described with three parameters in the model, leaf radius, orientation, and leaf density, where the first two determine the beampattern of each leaf. Compared with echoes collected from real trees, the simulation echoes are qualitatively accurate, i.e., they match in waveforms and also first-order statistics. Since the ground truth is known in the model, the three parameters were estimated with lasso model by selecting 40 features from each echo. The results have shown that estimation of one parameter with the other two known is usually successful with coefficient of determination close to one, and the classification still has reasonable accuracy when the number of known parameter is reduced to one. Besides, the three simplifications were examined with both experimental and simulation approaches. To assess the acoustic impact of leaf geometry on individual leaves, experiments were carried out by ensonifying leaves from both a single and different species. How the leaves' impulse responses change according to their equivalent radii was investigated. The simulation model of disks fits the experiments done with real leaves within one species and across species reasonably well. Shading effect is found to exist locally when two disks were 25 cm apart and were both in pulse direction. In addition, the inhomogeneous distribution of leaves was introduced by using the branching patterns of L-system. The evaluation of inhomogeneity in echoes produced with two distributions shows that there is always inhomogeneity in echoes, and L-system model does bring more inhomogeneity but not to the same extent as changes in the relative orientation between sonar beam and foliage do. / Ph. D. / Echolocating bats use ultrasonic waves to navigate and forage at night in the forest. They constantly emit pulses and analyze the returning echoes to perceive the surroundings. Foliage echoes are common and important input of their sensory systems, yet what accessible information is contained in foliage echoes for bats is not fully understood. Hence, this dissertation has built an efficient computer model to compute vegetation echoes. To simplify the problem, leaves with various shapes were approximated as circular disks. Besides, every leaf was assumed to be “visible” to sonar, in other words, even if one leaf was shaded by another in the pulse direction, it can still interact with sonar as if the front leaf didn’t exist. Then the leaves were uniformly distributed in the space. With the simplifications above, foliage can be described with three parameters, mean leaf radius, orientation, and leaf density. By varying the three parameters to match features of different trees, a large amount of echoes can be calculated efficiently. Compared with measured echoes from real trees, the simulation echoes are similar with them in terms of waveforms and probability density functions. If producing echoes with two parameters fixed and the third randomly chosen from certain range, the random parameter can be estimated with a linear model, lasso regression model, by extracting features from the echoes as inputs. The estimation is accurate. But if varying one of the two known parameters, the accuracy of estimation is largely reduced. Besides, the three simplifications were examined if they have impact on the simulation results. Impulse responses from leaf specimens were measured with a bio-mimetic sonar head in the anechoic chamber where noise and unwanted reverberations are largely weakened. Experiments were also carried out for two disks of same size by aligning them in the direction of sound emission to quantify shading effect, which shows that shading effect exists locally. Then branching patterns were introduced to the simulation model using L-system that consists of a set of rules to determine how branches grow. The results demonstrates that the simplifications do affect the model accuracy but the influence may be compensated.

Context. Procedurally generated content is a common way for companiesto save time and resources when creating modern video games.However, with generation of content there is often many variables controllingthe outcome that is tricky to get right. Objectives. The aim of this thesis is to research how people perceivethe branch density of trees used in video games. This will be done bycreating a foliage generation tool that is based on the functionality ofan L-system. The tool will be used to generate 12 trees with differentbranch densities which will be used for the questionnaire in the userexperiment. Method. A foliage generation tool has been created to be able togenerate trees with different branch and twig densities. The trees generatedwith the tool have been used in a user experiment in order tocome to a conclusion on how people perceive different branch densityin virtual trees. Result. Trees with higher branch and twig densities were rated higherthan trees with lower ones. The best rated tree in all regards was atree in the group with the second most main branches and had 0.6 intwig density. Conclusions. The results show that trees with a higher branch densitymade participants rate it as better looking in the user experiment.Although, trees with a high number of main branches and low twigdensity got the lowest score.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A pesquisa foi realizada com o objetivo de avaliar a decomposiÃÃo da folhagem de marmeleiro (Croton sonderianus), em funÃÃo da forma de acondicionamento e disposiÃÃo do material no solo na estaÃÃo seca e na estaÃÃo chuvosa. O experimento foi conduzido na Fazenda Experimental Vale do AcaraÃ, onde foram selecionadas duas Ãreas com 1 ha cada. Uma Ãrea apresentava a vegetaÃÃo preservada e a outra Ãrea sofreu aÃÃes antropogÃnicas. Foram acondicionados 30 g de folhagem de marmeleiro em 72 sacolas de decomposiÃÃo (que foram confeccionadas com malha telada de n 0 com 30 cm x 30 cm) as quais foram divididas em 3 tratamentos: sacolas com ambas as faces livres (A); sacolas com a face superior protegida por um plÃstico transparente (B), sacolas com a face superior protegida por lona branca (C). O delineamento experimental foi inteiramente casualizado em um arranjo fatorial de 3 x 2 x 2 x 2, sendo 3 tipos de sacolas x 2 Ãreas x 2 posiÃÃes x 2 estaÃÃes, com trÃs repetiÃÃes. Foi mensurada a temperatura ambiental, mÃxima e mÃnima, a temperatura do solo, assim como a umidade presente no mesmo, e a radiaÃÃo solar. As taxas de decomposiÃÃo real foram obtidas atravÃs de equaÃÃo, em que houve a subtraÃÃo da porcentagem inicial de biomassa vegetal pela quantidade restante nas sacolas ao fim de cada estaÃÃo. A forma de acondicionamento do material, as posiÃÃes em que os mesmos estavam assim como a influÃncia das estaÃÃes do ano e seus fatores abiÃticos caracterÃsticos, influenciaram na taxa de decomposiÃÃo da folhagem de marmeleiro, sendo que ocorrem maiores taxas de decomposiÃÃo na Ãrea preservada durante o perÃodo chuvoso. / The research was conducted to evaluate the decomposition of leaves of marmeleiro (Croton sonderianus), depending on the shape and arrangement of the packing material in the soil in the dry and rainy seasons. The experiment was conducted at the Fazenda Experimental Vale do AcaraÃ, where two areas were selected with 1 ha each. One area showed the preserved vegetation and other anthropogenic area suffered. Were placed 30 g of leaves of marmeleiro in 72 bags of decomposition (which were made with mesh screened from No. 0 to 30 cm x 30 cm) which were divided into three treatments: bags with both free surfaces (A); bags with the top surface protected by a transparent plastic (B), bags with the top surface protected by white canvas (C). The experimental design was completely randomized in a factorial arrangement of 3 x 2 x 2 x 2, and 3 types of bags x 2 x 2 locations x 2 seasons, with three replications. Was measured at ambient temperature, maximum and minimum soil temperature and the moisture present in it, and solar radiation. Decomposition rates were obtained by real equation, in which there was the subtraction of the initial percentage of plant biomass by the amount remaining in the bags at the end of each season. The form of packaging material, the positions in which they were as well the influence of the seasons and their abiotic characteristics, influence the rate of decomposition of leaves of marmeleiro, with higher rates of degradation occur in the preserved during the rainy season.