• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 323
  • 17
  • 2
  • Tagged with
  • 349
  • 349
  • 44
  • 43
  • 38
  • 37
  • 32
  • 27
  • 27
  • 25
  • 23
  • 21
  • 21
  • 20
  • 20
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Human disturbance affects the ecology and population dynamics of the tammar wallaby, Macropus eugenii, on Garden Island, Western Australia

Chambers, Brian Kevan January 2009 (has links)
[Truncated abstract] Understanding the effect that the disturbance of habitat by humans has on the population dynamics and ecology of wild animals is critical for the management of these populations. By understanding the demographic effects of disturbance the ways in which a population can be managed to increase or decrease its rate of change in size also become apparent. This thesis describes the effect that human disturbance, through the establishment of a large naval base, has had on the population dynamics and ecology of tammar wallabies (Macropus eugenii) on Garden Island, Western Australia. The disturbance of the environment on the HMAS Stirling Naval Base included the establishment of large areas of irrigated and fertilised couch grass (Cynodon dactylon) that increased and made virtually constant the amount of food available to the tammars in that area. In addition, traffic associated with the naval base resulted in large numbers of tammar wallabies being killed by vehicles. The effects of these disturbances were determined by comparing population dynamics, through vital rates of survival and fecundity and population growth rates, and spatial ecology, through the size of the animals' home ranges, in three areas of Garden Island. The three areas were the naval base (highly disturbed), southern bushland (adjacent to the naval base) and the northern bushland (undisturbed). The tammars on the naval base were in better body condition than those living in the two bushland areas of the island. ... When the impact of road-kills was removed, increased to 1.150.101 per year on the naval base and 0.960.076 per year in the southern bushland. Fecundity transitions, defined as the product of the rates of birth and pouch-young survival, and adult survival rates were lower in the bushland areas compared with the naval base in two of the three years, which were the main reasons for the lower estimates. There were no significant differences in the size of the tammars' home ranges between areas with modified or unmodified habitats or between the sexes (P>0.05). In summer the mean size of the home ranges was 3.90.66 ha, which was larger than winter when home ranges were 3.20.54 ha, but this difference failed to reach significance (P=0.058). These results indicate that the modification of the tammars' habitat has probably not caused significant changes in the size of the animals' home ranges. The size of the home ranges of tammar wallabies is likely to be determined by a complex interaction of many factors, and habitat modification alone has not been sufficient to cause substantial changes. The results presented in this thesis demonstrate that the disturbance caused by the establishment of the naval base on Garden Island has altered the population dynamics of the tammars wallabies, through increasing in the amount of food available to the tammars and through high numbers of road-kills. These results also demonstrate how gaining detailed knowledge of population dynamics can have direct application to managing the impact of disturbance on populations of wild animals.
172

Topics in Worora grammar / Mark Clendon.

Clendon, Mark January 2000 (has links)
Bibliography: leaves 526-532. / xxi, 532 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / A description of the grammar of Worora, a language from the north west Kimberley region of Western Australia, proceeds along pedagogical lines. Introducing the speakers of Worora and their history and society, and the nature of the land in which they used to live, as well as to the manner and circumstances in which this account came to be written; describing in outline six important lexical categories, essential to a basic understanding of the grammar. / Thesis (Ph.D.)--University of Adelaide, Centre for European Studies and General Linguistics, 2001?
173

Responses of Posidonia australis Hook.f. and Posidonia sinuosa Cambridge et Kuo transplants to nitrogen, phosphorus and iron additions in Oyster Harbour, Western Australia, with focus on root development

Hovey, Renae Kathleen January 2009 (has links)
[Truncated abstract] There is a well-documented global decline of seagrass meadows in response to anthropogenic pressures. Transplantation of rhizome fragments into denuded areas has been used to enhance natural recovery but nutrient limitation and poor root growth may contribute to low success rates. Addition of nutrients to sediments has been proposed as a means of enhancing growth and survival of seagrass transplants by alleviating nutrient limitation but there is limited information of the effects of nutrient additions to seagrass transplants, particularly root development and morphology. In addition to nutrient limitation, sulphide accumulation in sediments with high organic matter has been shown to reduce seagrass growth and experimental iron additions have been shown to enhance seagrass growth by buffering the development of reduced conditions in organic rich sediments. This thesis examines responses (growth, morphology and nutrient status) of Posidonia australis and Posidonia sinuosa transplants to nitrogen (N), phosphorus (P) and chelated iron (Fe EDTA) additions, and includes a detailed investigation of root growth and morphology in response to these additions. Experiments were carried out in underwater plots in Oyster Harbour, a sheltered estuarine inlet with seasonal river flow, located on the southern coast of Western Australia. In the first experiment, nutrients (N, P and N+P) and Fe EDTA were added to sediment underlying transplants at the end of summer (March 2005). ... Nitrogen (both N and N+P) addition also reduced overall biomass allocation to roots. Nitrogen concentrations increased with N addition in P. sinuosa only but both species had more negative d15N values with N and N+P addition indicating that added N had been taken up. In contrast, P addition had little effect on root growth, and P concentrations only increased in P. australis. However, tissue concentrations of Zn, Co, and Mo in both species increased with P addition. Roots showed limited morphological variation (total root length, mean root diameter, root fineness, specific root length, surface area) in response to nutrient addition. Combined N and P addition increased lateral root density (branches m-1) but had no effect on other morphological parameters of the root compartment. Iron addition had no effect on P. sinuosa but P. australis transplants significantly reduced root growth and productivity, particularly in spring/summer growth period, due to lower primary and lateral growth rates. Overall, N or P additions did not enhance growth although these nutrients were taken up. Iron additions also had little effect on transplant growth. Seagrass transplants had significant root growth although they appeared not to respond to nutrient or iron addition. Both species produced extensive root systems capable of taking up sediment nutrients, which suggests that root development was not a limiting factor in establishment and growth of transplants in the temperate estuary, Oyster Harbour.
174

This Other Eden

Kathryn Burns January 2007 (has links)
Doctor of Philosophy / This thesis explores the sense of place formed during childhood, as remembered by adult Australians who reconstruct their youth through various forms of life writing. While Australian writers do utilize traditional tropes of Western autobiography, such as the mythology of Eden and the Wordsworthian image of the child communing with Nature, these themes are frequently transformed to meet a uniquely Australian context. Isolation and distance from Europe, and the apparent indifference of our landscape towards white settlement, have received much critical attention in Australian studies generally and, indeed, broadly influence the formation of children’s sense of place across the continent. However, writers are also concerned with the role of place on a more local level. Through a comparison of writing from Western Australia, Queensland and Victoria, this thesis explores regional landscape preoccupations that create an awareness of local identity, variously contributing to or frustrating the child’s sense of belonging. Western Australian writing is dominated by images of isolation, the fragility of white settlement in a dry land lacking fresh water, and a pervasive beach culture. A strong sense of the littoral pervades writing from this region. Queensland’s frontier mythology is of a different flavour: warm and tropical, nature here is exuberant, constantly threatening to overwhelm culture, already perceived as transient due to the flimsy aspect of the “Queenslander” house. Writing from Victoria, to some extent, tends to more closely follow English models, juxtaposing country and city environments, although there is a distinctly local flavour to many representations of urban Melbourne and its flat, grid-like organization. As Australian society becomes more concentrated on the coastal fringe, the beach is an increasingly significant environment. Though more prominent in writing from some regions than others, coastal imagery broadly reflects the modern Australian’s sense of inhabiting a liminal zone with negotiable boundaries.
175

This other Eden: exploring a sense of place in twentieth century reconstructions of Australian childhoods

Burns, Kathryn January 2007 (has links)
Doctor of Philosphy(PhD) / This thesis explores the sense of place formed during childhood, as remembered by adult Australians who reconstruct their youth through various forms of life writing. While Australian writers do utilize traditional tropes of Western autobiography, such as the mythology of Eden and the Wordsworthian image of the child communing with Nature, these themes are frequently transformed to meet a uniquely Australian context. Isolation and distance from Europe, and the apparent indifference of our landscape towards white settlement, have received much critical attention in Australian studies generally and, indeed, broadly influence the formation of children’s sense of place across the continent. However, writers are also concerned with the role of place on a more local level. Through a comparison of writing from Western Australia, Queensland and Victoria, this thesis explores regional landscape preoccupations that create an awareness of local identity, variously contributing to or frustrating the child’s sense of belonging. Western Australian writing is dominated by images of isolation, the fragility of white settlement in a dry land lacking fresh water, and a pervasive beach culture. A strong sense of the littoral pervades writing from this region. Queensland’s frontier mythology is of a different flavour: warm and tropical, nature here is exuberant, constantly threatening to overwhelm culture, already perceived as transient due to the flimsy aspect of the “Queenslander” house. Writing from Victoria, to some extent, tends to more closely follow English models, juxtaposing country and city environments, although there is a distinctly local flavour to many representations of urban Melbourne and its flat, grid-like organization. As Australian society becomes more concentrated on the coastal fringe, the beach is an increasingly significant environment. Though more prominent in writing from some regions than others, coastal imagery broadly reflects the modern Australian’s sense of inhabiting a liminal zone with negotiable boundaries.
176

Children in families in communities : a modified conceptual framework and an analytic strategy for identifying patterns of factors associated with developmental health outcomes in childhood

Kendall, Garth Edward January 2003 (has links)
Mental health reflects an array of causal influences that span biological, psychological, and social circumstances, with resultant underlying causal pathways to poor mental health outcomes in childhood that are complex. Key features of this complexity are reciprocal interactions between person and environment that take place over time. The core of this thesis seeks to attend to the complexity of development to move the field of developmental health forward toward greater explanation, and more successful prediction and prevention. The focal point of the thesis is the psychosocial determinants of childhood mental health, the resource domain of the developing child, and the interplay between characteristics of the individual child, the family, and the community. The eventual goal is to better understand why and how socioeconomic circumstances impact on developmental health. One component of this thesis focuses on the expansion of extant developmental theory. The other component focuses on the development of an analytic strategy that more appropriately reflects the intricacies of this theoretical expansion. In the process, data are analysed, principally as a heuristic strategy, to illustrate the analytical approach needed to support the theoretical framework. The specification of a bioecological conceptual framework suitable to guide research and policy in developmental health is the first principal objective of the thesis. A critical examination of the resource framework proposed by Brooks-Gunn, Brown, Duncan, and Anderson Moore (1995) reveals it to be centred on family and community resources, but otherwise silent with respect to the physical and psychological resources of the child. The quintessential point of this thesis is that theory in developmental health must be able to account for the contribution individuals make to their own development. A modified resource framework is proposed that acknowledges financial, physical, human, and social capital, within the domains of the individual child, the family, and the community. The second principal objective of the thesis, the development of analytical methods that focus on the individual child and the complexity of data generated by this theoretical approach, is then introduced. Theory and method are thus integrated when comprehensive measures of characteristics in multiple domains across developmental periods are modeled using longitudinal data from the Western Australian Pregnancy Cohort (Raine) Study (Newnham, Evans, Michael, Stanley, & Landau, 1993). The mothers of 2,860 children were enrolled at 18 weeks in pregnancy and the children have been followed at birth, one, two, three, five, and eight years of age. Eighty-nine per cent (2,537 /2,860) of families were available for follow-up at eight and 74 per cent (2,126/2,860) of families responded. Extensive demographic, psychological, and developmental data were available for the children and their families and a limited amount of data were available for the communities in which they reside. A measure of mental health morbidity, the Child Behaviour Checklist (Achenbach, 1991), was available for the children at two, five, and eight years of age. In the first instance, dichotomous summary variables are derived for the demographic, psychological, and developmental variables of interest. Variables are then selected for inclusion in one of several explanatory models. To create a mathematical representation of resource characteristics, the information for each child is concatenated as a series of binary strings. Frequency tabulation is then used to aggregate the data and odds ratios are calculated to determine the degree of risk associated with each string of code, or pattern of factors relative to a nominated mental health outcome. The results provided a scaffold from which this theoretical and analytical approach is compared and contrasted with the reviewed literature. Two principal themes of investigation are pursued. The first theme to be examined is the interplay between characteristics of the child, family, and community and the contribution children make to their own development. The specific approach models the interaction between selected characteristics of the child, family and community in each of four developmentally significant time periods. The theoretical position adopted in the present study suggests that the effect of any personal or contextual factor on later development, if a relationship does truly exist, is most likely to be differential. That is, it is a combination of influences that determines developmental outcomes for children, not any single factor acting independently. The modelling process demonstrates that, for the children involved, personal and contextual factors impact mental health differentially depending on various other individual, family and/or community characteristics. The modelling process identifies patterns of factors that impact relatively small, but significant, numbers of children because the models focus on the effect for individual children rather than the effect for the group. For example, one model suggests that the effect of intra-uterine growth restriction for the group as a whole may be minimal, but the impact for some children could be critical depending on the combination of family and community influences, such as the mothers level of education, the family’s experience of significant life stress, and residence in a relatively disadvantaged community. The second theme to be examined is the possibility that the accumulation of resource deficits or risk characteristics, over time, amplifies the likelihood of mental health problems in childhood. The approach models selected characteristics of the child in each of the four periods of development collectively, and it also models selected characteristics spanning each of the four time periods discretely. The results suggest that latency, pathway, and recency effects may operate simultaneously, and that timing and accumulated burden may both be important determinants of risk. For example, with regard to children whose family experienced life stress, these three effects operated in a systematic way to increase the degree of risk of a mental health problem. In summary, the aggregation of data at the individual level is a productive approach in seeking to explain population level social phenomena. While seemingly paradoxical, the identification of the joint, interactive effects between individual, family, and community characteristics, better allows for the quantification of family and community characteristics operating through multiple causal pathways.
177

The biology and fishery of Roe's abalone Haliotis roei Gray in south-western Australia, with emphasis on the Perth fishery

Hancock, Andrew (Boze) T. January 2004 (has links)
The Roe’s abalone (Haliotis roei) fishery near Perth, Western Australia, is uniquely accessible, and highly vulnerable to overexploitation. The sustainability of this intensively utilized fishery requires robust assessment. To facilitate an assessment, this research aimed to provide rigorous and detailed biological information with appropriate interpretation. Four critical aspects of the species’ biology and population dynamics were investigated: (1) the stock structure; (2) the recreational catch; (3) an appropriate growth curve and description of size at age; and (4) abundance measures against which to assess the impact of fishing mortality. Allozyme electrophoresis was used to investigate stock structure across the species’ distribution. Standardized variance in allelic frequencies between 10 sites in south-western Australia indicated high levels of gene flow across the 3000 km sampled (mean FST = 0.009). An isolation-by-distance was evident when pairwise measures of GST were related to geographic distance (r=0.45, P<0.001). The area of complete genetic mixing was estimated from samples within the Perth fishery to be less than the distance between the two nearest sites, or 13 km. Consequently, the Perth fishery comprises numerous discrete stocks, each requiring independent assessment. A possible mechanism for this population structure is the retention of larvae in the wind driven currents oscillating in the near-shore lagoons, with rare pulses of long distance dispersal via the southerly Leeuwin current, running further offshore. The presumed impact of intensive recreational fishing, combined with substantial commercial quotas for the Perth fishery, had led to tight restrictions on fishing effort, without any quantitative measure of the recreational catch. A stratified creel survey was adapted to estimate the effort, catch rate and mean weight of abalone harvested by the recreational sector. Catches were estimated for reef complexes, or stocks, of less than 10 nautical miles (18.5 km) of coast. Between 1997 and 2000 the recreational catch varied from 30 to 45 tonnes whole weight, approximately equivalent to the commercial quota of 36 tonnes. On average 88% of the recreational catch came from two stocks, while 98% of the commercial catch came from these two, and one additional, stocks. The incidental mortality from recreational fishing, measured as the number of abalone left dead on the reef as a proportion of the estimated catch, was approximately 7% and 20% at two sites surveyed. Spatial and temporal patterns of growth were examined on the west coast of Western Australia. Growth increments were measured for abalone larger than about 30 mm from tagging studies at five sites in the Perth fishery, a site at the northern extent of the species’ distribution and a site in the southwest. Mean annual growth increments of the 0+ year class were obtained by fitting components to length frequencies from five sites in the Perth fishery, and combined with growth increments from each Perth tag site for model fitting. A von Bertalanffy growth curve provided a slightly better fit to the tag data, but a Gompertz growth curve was a much better fit when the mean increment from the 0+ to 1+ cohort was included, with the inflection occurring at about 40 mm, the size at sexual maturity. There was no difference in annual growth between the two years studied. There was significant variation in growth between the reef platform and adjacent sub-tidal reef, but this variation was site specific and faster growth rates were not consistently associated with either habitat. There was no latitudinal trend in growth rate. Growth at the Perth sites was the fastest and similar at all five sites with growth increments greater in summer than in winter. Size and abundance of abalone were measured using fixed transects and quadrats. Abalone densities were highest on the outer edge of the platform, intermediate in the middle of the reef platform, and lowest on both the inner platform and the sub-tidal reef. The pattern of mean lengths of abalone was the inverse of the density. Mean length and abundance were driven by the presence of post-settlement juveniles on the outer and middle reef habitats. There was a high spatial variation in abundance, with densities varying between transects at the same site, but the trend between years for each transect at a site was not significantly different. Abalone abundances, by size class, were examined from sites sampled between 1996 and 2002. A low density of post-settlement juveniles at all sites in 1997 was reflected in low densities of the 1+ and 2+ year classes in subsequent years. Abalone abundances at an unfished site were steady over the seven years. Two sites were located within each of the main stocks utilised by the recreational fishery. Abundance was stable or increasing in one stock, corresponding to a stable total catch. In the second stock the total catch increased over time and abundances declined. Perth is the focus of the Roe’s abalone fishery, with recreational and commercial fishers take about equal shares of the annual catch. Stocks are highly subdivided, with most of this catch coming from only 3 stocks occupying about 20 nautical miles of coast. Growth rates were found to be lower than previous estimates, and more similar to other commercial species of abalone. All life history stages are highly habitat specific, particularly the recruits, and the distribution and abundance through time indicate that the main stocks are near, or slightly over, the limit of sustainable fishing.
178

Evolution in sown mixtures of subterranean clover (Trifolium subterraneum L.)

Nichols, Phillip Geoffrey Harwood January 2004 (has links)
[Truncated abstract] Evolution in two genetically diverse sown populations of subterranean clover (Trifolium subterraneum L.) was examined over 16 years at Mt Barker, a long growing season site, and at Nabawa, a short growing season site, in south-west Western Australia. One population consisted of a mixture of 40 strains sown in equal proportions, while the other was a bulk-hybrid population consisting of F2 seed from 253 crosses. Seed harvested annually and kept in cold storage was grown in an irrigated common garden at the University of Western Australia Field Station at Shenton Park, along with samples of the ancestral mixtures, to examine changes within these populations. Evolution in the strain mixture populations was measured by changes in strain frequency; strains were considered ecologically successful if their relative contribution was maintained or increased from that at sowing. Mixtures containing an additional 12 cultivars were also sown at each site to examine short-term population changes. The relative importance of 38 attributes measured in single-strain swards and spaced plants at Nabawa and Mt Barker was then related to strain success in mixtures at each site. Evolution in the bulk hybrid populations was measured in spaced plants at Shenton Park by changes in mean values and variability of 26 attributes. The ancestral populations evolved into markedly different populations at each site. Most evolution occurred within three years of sowing, due to elimination of poorly adapted genotypes. Within sites, the direction of selection was similar for both mixtures. In the strain mixture populations, different strains became dominant at each site. Divergent strains, those not identical to the sown strains, were significant components of the populations, particularly at Mt Barker, but their frequency did not increase. In the bulk hybrid populations, changes occurred in the means of 20 characters and variability declined in 11 characters at one or both sites. Appropriate flowering time was fundamental for success in both environments. At Nabawa, early flowering was crucial, while successful genotypes at Mt Barker were midseason and late flowering. Flowering time in both environments was a compromise between sufficient earliness for adequate seed production prior to the onset of summer drought, and deferment for as long as possible to allow plants to develop maximum size to compete for light in spring. The balance between these two competing forces differed in response to length of the growing season at each site
179

Form and reform : affective form and the garden suburb

Stickells, Lee January 2005 (has links)
This thesis establishes the concept of affective form as a means of examining urban design – being the intersection of architecture, planning and landscape – in relation to techniques of governance. Affective form broadly describes a built environment where people are encouraged to amend, or govern, their actions according to particular socio–political ideas. Exploration of the concept’s application as a theoretical tool is undertaken here in order to generate a means of discussing the ethical function of urban design. The emergence of notions of affective form will be located in the eighteenth century, alongside the growing confidence in the ability for humankind to effect social and cultural progress. In a series of examples, stretching throughout the twentieth century, the implicit relation of planning, architectural and landscape form to social effect is discussed. The language, and design models, used to delineate affective form are described, alongside discussion of the level of intentionality apparent in the conceptions of urban form’s social effect. Critique through affective form allows an analysis that brings together the underlying utopian elements of projects – the traces of ideology and sociological theories – with an evaluation of the formal concepts projected. As the second area of investigation, the city of Perth in Western Australia provides a contextual focus for the examination of concepts of affective form. Through a series of appropriations of urban design models a suburban archetype emerged in Perth of a planned, homogenous field of low–rise, single–family, detached dwellings within a gardenesque landscape. The process of appropriation is described as a continuing negotiation between local expectations and the implicit conceptions of affective form within the imported models. Connecting the two primary concerns of the thesis, the ability of form to influence social change and the evolution of Perth’s garden suburb ideal, is the association of that developing garden suburb model with notions of affective form. The associations are outlined through three case studies. The first is an account of the planning of the City of Perth Endowment Lands Project during the 1920s. The second describes the planning and architecture of the athlete’s village built for the VIIIth British Empire and Commonwealth Games held in Perth in 1962. The third study details the development in the 1990s of Joondalup, a satellite city in the Perth metropolitan region. The account of Perth’s garden suburb ideal is intertwined with the consideration of the varying ways in which the conceptualization of affective form has been expressed. Each case study is contextualized by a preceding chapter that discusses the particular conceptions of affective form used in its examination. Thus the main body of the thesis comprises three parts – each associated with a case study, each containing two linked chapters
180

Soil development, plant colonization and landscape function analysis for disturbed lands under natural and assisted rehabilitation

Setyawan, Dwi January 2005 (has links)
[Truncated abstract] Spontaneous plant growth and soil development occur at disturbed sites with their extent and nature being variously affected by soil fertility status, local climate and topographic conditions. Soil-plant interactions can be diverse and site-specific within a disturbed landscape. The main purpose of the present study is to evaluate soil characteristics and landscape indices in relation to natural plant growth and soil development under different conditions and for diverse materials. A comprehensive study has been carried out to evaluate spontaneous soil development and plant colonization on various regolith materials at a railway cutting near Jarrahdale bauxite mine and on various substrates comprising waste rock, weathered regolith and replaced topsoil at Scotia (Norseman, Western Australia) and Kelian (East Kalimantan, Indonesia). At Jarrahdale soil development has occurred slowly over 36 years in relation to morphological changes in surface horizons. Soils at several locations exhibit substantial changes in color, texture and structure. The slow soil development is primarily due to low biomass and litter contributions (˜1 Mg/ha) from colonizing plants (e.g. Dryandra sessilis, Eucalyptus marginata and low shrubs) on the cutting shelf and slow litter decomposition. Nutrient accumulation is up to 5 kg N/ha, and 0.5 kg/ha for P and K. Surface soil samples from Jarrahdale are generally acidic (pH < 5.1) and contain low concentrations of total soil carbon (20 g/kg) and nutrients of total nitrogen (0.73 g/kg), bicarbonate-extractable phosphorus (bic-P) (< 2 mg/kg), bic-K (37 mg/kg) and total exchangeable bases (<1.1 cmol/kg, with 24 % base saturation). Soil properties at the Scotia waste dump are mainly associated with alkaline (mean pH = 9) and saline conditions (EC1:5 = 1.01 dS/m). Exchangeable base values are high with average concentrations of exchangeable Ca of 18 cmol/kg and exchangeable Mg of 6 cmol/kg, thus these elements are not a limiting factor for plant nutrition. Patchy plant growth on the waste dump is mostly related to differences in water availability in the arid region and to salinity such that halophytes (saltbushes Maireana and Atriplex) colonize many parts of the waste dump together with some Melaleuca and Eucalyptus species

Page generated in 0.0631 seconds