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  • 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.
181

The role of geology, geomorphology, climate and vegetation, in controlling spatial and temporal changes in groundwater discharge from weathered crystalline basement aquifers in southwestern Australia

Rutherford, Jasmine Lee January 2006 (has links)
[Truncated abstract] The Collie River drainage basin is an important water resource catchment in southwestern Australia. Salinisation of a major water supply within the catchment, the Wellington Reservoir, has arisen due to changes in the water and salt balance in response to land clearing over saprolite aquifers. Paired catchment studies, the Collie Experimental Catchments (CECs), established in the early 1970’s in high and low rainfall areas increased our understanding of water and salt (predominantly chloride) movement in these aquifers through the collection and analysis of high resolution spatio-temporal data. However, the conceptual models developed from this work take little account of landscape heterogeneity, and this has caused problems in subsequent modelling studies, where success in calibrating stream flow has been countered by difficulties in predicting salt loads. The challenge remains to better describe variability in the Collie landscape and understand the influence of climate, vegetation, geology and geomorphology on observed water and salt fluxes. The release of salt from the lower saprolite aquifer and the role of the surficial aquifer in buffering groundwater discharge were investigated. The acquisition, analysis and interpretation of new regolith and geophysical data in 2001-2003 from the CECs, together with data from a high resolution digital elevation model, and existing drilling information, were used to construct a geologicalgeomorphological compartment framework, to observe changes in aquifer behaviour ... Significant differences in the salt flux from compartments have been noted at a range of scales, with implications for both water resource and land management. The approach developed to identify compartments and assess their efficiency could be simplified, using catchment critical parameters determined from geological and geomorphological characteristics. As a consequence, the implementation of a compartment framework in catchments with saprolite aquifers should allow for more informed decisions to be made in the selection of sites for revegetation strategies or the development of engineering works. This is particularly important in the Collie Catchment where reclamation scenarios are currently being discussed. Consideration of the catchment as a compartmentalised system would help manage salt loads in the Collie River and return the Wellington Reservoir to a functional water resource.
182

Development of a culturally sensitive program delivering cardiovascular health education to indigenous Australians, in South-West towns of Western Australia with lay educators as community role models

Owen, Julie January 2006 (has links)
[Truncated abstract] Indigenous Australians suffer cardiovascular disease (CVD) at a rate six times greater than the general population in Australia and while the incidence of CVD has been reduced dramatically amongst the majority of non-indigenous Australians and amongst Indigenous populations in other countries in the last 30 years, there has been little change in the figures for Aboriginal Australians, showing that heart health campaigns have little impact, for this group of people. Aims : The principal aims of this study were firstly, to determine and record the barriers to the development and delivery of CVD prevention programs amongst Indigenous Australians and secondly, to develop an alternative, effective and culturally sensitive method of delivering heart health messages. Methods and results : The study was qualitative research undertaken in three South-West towns of Western Australia where the incidence of CVD was high amongst the Aboriginal community members. The use of semi-formal interviews, informal individual consultation, observation, and focus groups were methods implemented to obtain information. The first phase of the research was to identify the barriers which affected the Aboriginal Health Workers’ ability to deliver specialist educational programs. Questionnaires and interviews with the Aboriginal Health Workers and other health professionals in the towns, and community focus groups were undertaken in this phase of the study. The second phase of the research was aimed at developing an alternative strategy for delivering heart health messages. The focus changed to adopt more traditional ways of passing on information in Indigenous communities. The idea of small gatherings of friends or family with a trusted community member presenting the health message was developed. The third phase of the research was to implement this new approach. Lay educators who had been identified within focus groups and by Aboriginal Health Workers were trained in each of the towns and a protocol involving discussions of health issues, viewing a video on CVD, produced by the National Heart Foundation, sharing in a ‘heart healthy’ lunch and partaking in a ‘heart health’ knowledge game which was developed specifically for the gatherings. Several of these gatherings were held in each of the towns and they became known as ‘HeartAware parties’.
183

Water flow in the roots of three crop species : the influence of root structure, aquaporin activity and waterlogging

Bramley, Helen January 2006 (has links)
[Truncated abstract] The hydraulic properties of the roots of three crop species important to Western Australia were examined: wheat (Triticum aestivum), narrow-leafed lupin (Lupinus angustifolius) and yellow lupin (L. luteus). Generally, the hydraulic conductivity (Lpr) of root systems differs between species and can change in response to adverse conditions. To determine the significance of root anatomy and aquaporin activity on the pathway of water flow through roots, water flow was measured across cell membranes, individual roots and whole root systems. The combination of measurements identified that wheat and lupin roots have contrasting hydraulic properties. Wheat roots absorb water preferentially in the apical region, whereas lupin roots appear to absorb water more evenly along the entire root length. Lupin roots have a greater axial hydraulic conductance than wheat, due to more abundant xylem vessels and axial conductance increases with root length, in conjunction with xylem vessel development. However, water flow through the radial pathway is the limiting factor in whole root hydraulic conductance, in all species. Modelling and the inhibition of aquaporin activity with mercuric chloride demonstrated that radial water flow in wheat roots occurs by a combination of the cell-to-cell and apoplastic pathways, but in lupins, water flow appears to be predominantly apoplastic. Despite the presence of aquaporins in root cell membranes of all species, their role in regulating bulk water flow across roots is not clear in lupins, because of the significance of the apoplastic pathway ... After draining the chambers, the root systems of yellow lupin resumed growth, but there was no subsequent recovery in narrow-leafed lupin root systems. The growth and survival strategies of wheat and lupin root systems are disparate. Wheat root systems are comprised of numerous fine, highly branched, individual roots that extract water near the root tips and have the ability to regulate flow. These attributes may be advantageous in non-uniform or variable environments. Moreover, the ability of wheat roots to regulate flow may not only support survival during waterlogging, but also enhance recovery. In comparison, lupin root systems are designed like conduits, for the rapid uptake and transport of water when conditions are favourable. However, their thick taproots and lack of regulation of water transport or anatomical changes make them unsuitable for very wet soils.
184

The impact of dryland salinity on Ross River virus in south-western Australia : an ecosystem health perspective

Jardine, Andrew January 2007 (has links)
[Truncated abstract] A functional ecosystem is increasingly being recognised as a requirement for health and well being of resident human populations. Clearing of native vegetation for agriculture has left 1.047 million hectares of south-west Western Australia affected by a severe form of environmental degradation, dryland salinity, characterised by secondary soil salinisation and waterlogging. This area may expand by a further 1.7-3.4 million hectares if current trends continue. Ecosystems in saline affected regions display many of the classic characteristics of Ecosystem Distress Syndrome (EDS). One outcome of EDS that has not yet been investigated in relation to dryland salinity is adverse human health implications. This thesis focuses on one such potential adverse health outcome: increased incidence of Ross River virus (RRV), the most common mosquito-borne disease in Australia. Spatial analysis of RRV notifications did not reveal a significant association with dryland salinity. To overcome inherent limitations with notification data, serological RRV antibody prevalence was also investigated, and again no significant association with dryland salinity was detected. However, the spatial scale imposed limited the sensitivity of both studies. ... This thesis represents the first attempt to prospectively investigate the influence of secondary soil salinity on mosquito-borne disease by combining entomological, environmental and epidemiological data. The evidence collected indicates that RRV disease incidence is not currently a significant population health priority in areas affected by dryland salinity despite the dominant presence of Ae. camptorhynchus. Potential limiting factors include; local climatic impact on the seasonal mosquito population dynamics; vertebrate host distribution and feeding behaviour of Ae. camptorhynchus; and the scarce and uneven human population distribution across the region. However, the potential for increased disease risk in dryland salinity affected areas to become apparent in the future cannot be discounted, particularly in light of the increasing extent predicted to develop over coming decades before any benefits of amelioration strategies are observed. Finally, it is important to note that both dryland salinity and salinity induced by irrigation are important forms of environmental degradation in arid and semi-arid worldwide, with a total population of over 400 million people. Potential health risks will of course vary widely across different regions depending on a range of factors specific to the local region and the complex interactions between them. It is therefore not possible to make broad generalisations. The need is highlighted for similar research in other regions and it is contended that an ecosystem health framework provides the necessary basis for such investigations.
185

The Lighthouse keeper's wife, and other stories (novel) ; and Ceremony for ground : narrative, landscape, myth (dissertation)

Temperton, Barbara, January 2007 (has links)
The focus of this project is on poetry, narrative, landscape and myth, and the palimpsest and/or hybridisation created when these four areas overlay each other. Our local communities' engagement with myth-making activity provides a golden opportunity for contemporary poets to continue the practice long established by our forebears of utilising folklore and legendary material as sources for poetry. Keeping in mind the words of M. H. Abrams who said
186

The conservation status of aquatic insects in south-western Australia

Karen Elizabeth Sutcliffe January 2003 (has links)
Freshwater ecosystems in south-western Australia have been extensively altered over the last two centuries as a result of human activities. The effect this has had on aquatic fauna, particularly invertebrates, is largely unknown because of inadequate knowledge of the pre-existing fauna. Future changes in the composition of aquatic fauna will also go undetected unless current distributions of existing species are well documented. This thesis addresses the problem by investigating the current distributions and conservation status of aquatic insects in south-western Australia from three orders: Odonata, Plecoptera and Trichoptera. Extensive distributional data was collected by identifying larval specimens from a large number of samples collected throughout the south-west as part of an Australia-wide macroinvertebrate bioassessment project. In addition, a database created from a species-level biological study of the wheatbelt region of Western Australia was utilised, and previously published records of occurrence for species within the south-west were compiled. These results were then used to assess the conservation status of each species using the IUCN red list criteria. Environmental parameters measured at time of sampling were also examined using logistic regression to determine which factors are important in influencing the distributions of aquatic insects in south-western Australia. The conservation value of sites based on Odonata, Plecoptera and Trichoptera compositions was also determined and the degree of protection provided for sites of high conservation value investigated.The high rainfall forested region of the south-west was found to be important for a large number of species, including the majority of those found to be rare and/or restricted. Overall, 37% of species were found to be threatened, with the Trichoptera containing both the greatest number and highest proportion of threatened species. Logistic regression results generally agreed with the distributions obtained for each species, with rainfall and other parameters indicative of streams in the headwaters of forested catchments being positively associated with species found to be restricted to the high rainfall region. Two parameters known to be affected by human disturbance in the south-west, conductivity and nutrient concentrations, were found to be important in determining the occurrence of many species and this could have important consequences for aquatic insect conservation. Widespread species occurring within the low rainfall region of the south-west did not show as many significant relationships to measured environmental parameters, possibly due to their greater ecological tolerances and adaptations which allow them to persist in a low rainfall environment. The implications of results are discussed, and recommendations for the conservation and management of aquatic insects in south-western Australia are given.
187

Plant Communities of Greenstone Hills of the Eastern Goldfields of Western Australia as Analogues for the Rehabilitation of Rocky Waste Dumps

chalwell@yahoo.com.au, Shane Thomas Samuel Chalwell January 2003 (has links)
The vegetation of greenstone hills in the Kalgoorlie area of the Eastern Goldfields region of Western Australia was studied to identify the key environmental influences on community and species distribution. This information was needed to determine if plant communities of the hills could provide analogues for the rehabilitation of waste rock dumps that are produced as a consequence of open cut mining. The ridges, slopes and flats adjacent to the main slope were examined and the floristic data sorted into communities. Two structurally and floristically distinct alliances were identified, one dominated by eucalypt species and the other by Acacia quadrimarginea. The eucalypt woodland displayed a taller upper stratum and few groundlayer species and was the dominant vegetation of the flats at the base of the hills. The acacia community was a low woodland and is the dominant vegetation of the hill slopes. Both communities were dominant at an equal number of sites on the ridges of the hills. An investigation of the environmental variables found that edaphic, rather than topographic, factors were responsible for the community distribution on the hills. The eucalypt woodland showed a strong affinity to soils derived from calcrete, which had higher levels of electrical conductivity and lower exchangeable sodium percentages than the soils of the acacia low woodland. Under such conditions, the clay fraction of the soil remains in a more flocculated state allowing higher rates of water infiltration and hydraulic conductivity compared to the acacia soils. Soil nutrients were found to have a secondary influence on community distribution and had a greater effect on species distribution within alliances. A study of the seasonal variation in water content of the soils showed that more moisture is retained in the upper soil horizons in the acacia community than in the eucalypt community during the wetter part of the year, indicating the acacia soils had poorer infiltration properties than the eucalypt soils. The distribution of drought tolerant species such as A. quadrimarginea and Prostanthera incurvata was found to be correlated to soil moisture content of the dry season whilst no correlation was found for the eucalypts at any time of the year. Seasonal comparisons of leaf moisture content and xylem pressure potential showed that the eucalypts maintained their total leaf moisture content throughout the year whereas species such as A. quadrimarginea and Allocasuarina campestris recorded high levels of desiccation of their leaf tissue over the summer. The eucalypts also maintained a more consistent pre-dawn xylem pressure potential throughout the year than either A. quadrimarginea or the shrub species Dodonaea microzyga, indicating a greater degree of stomatal control and access to a more consistent soil water supply. The eucalypts require access to a greater soil volume than the acacias or shrubs in order to ensure sufficient water supplies for the maintenance of tissue moisture levels throughout the year. In this way, the eucalypts are able to effectively avoid the summer drought, whereas the acacias and shrubs are able to tolerate desiccation of their leaf tissues over this period. Investigations of the germination requirements and early seedling survival of prominent species from the greenstone hills indicated that fire may be a factor in the regeneration of most hills species. All studied species were either tolerant of or responded positively to the application of dry heat. In relation to seedling establishment on waste dumps, increasing the soil moisture content of waste dump soils increased the germination rate of most species but did not result in greater seedling survival at the end of the first summer. The provision of microsites which encouraged root development and provided protection for the young seedlings was found to be more important in reducing mortality rates in the first year than increasing the total germination. The study emphasized the importance of physical soil factors and the soil moisture regime in the distribution of eucalypt and acacia communities on the greenstone hills. A species’ response to drought stress strongly influences its ability to compete for soil water on different soil types. The eucalypts studied in this project dominated on soils where there is better recharge of subsoil water reserves which can be accessed over the summer period to maintain tissue water levels. Acacias are tolerant of tissue desiccation and will compete successfully on shallower soils and where hydraulic conductivity is poor. Although the project was valuable in identifying water relations as the main control on community distribution on the hills, waste dumps are not strictly analogues of intact greenstone hills due to the differences in rock type and profile formation. Electrical conductivity levels are also higher due to extraction processes. However, the environmental relationships of the different species show that the more drought tolerant species such as Allocasuarina campestris, Acacia quadrimarginea and understorey species associated with them, may be suitable species to form the basis of vegetation reinstatement on waste dumps in the Kalgoorlie region.
188

Declared guilty, a never-ending story : an analysis of the impact of the criminal justice system upon the self

bsteels@iinet.net.au, Brian Steels January 2005 (has links)
This study explores the experience of people who have been publicly declared guilty. It retells the narratives of offenders from the point of arrest through to conviction and, where relevant, imprisonment and release. The experiences of close relatives are also explored and provide an important part of the thesis. These accounts are set against the institutional context of the criminal justice system and a systemic account of police, courts, prisons and community corrections is provided. The main aim of the study is to investigate and document the impact of the criminal justice process on offenders’ sense of ‘self’. At a theoretical level, the study is informed by symbolic interactionism, particularly the work of Erving Goffman. This enables the development of insights into issues such as loss, shame, humiliation and loss of self. The asymmetrical power relationship in which these feelings are engendered and maintained is emphasised. At the same time, the study records the level and types of resistance among the subjects of the criminal justice system. The findings are significant for our sociological understandings of the impact of being declared guilty, for they suggest that the criminal justice process per se contributes to a severely damaged self, and that the subjective experience of ‘being found guilty’ starts at the moment of arrest and persists well after sentencing as subjects try to re-integrate into the community with a record of conviction. The study also suggests that these processes are not passively absorbed by subjects. As well as describing feelings of shame and loss, those participating in the research talked about the unfairness of the system, their preparedness to resist in numerous ways, and of their longing for an older, better life in which their sense of self was undamaged. The study concludes by arguing that profound change to the culture of the criminal justice system is needed if rehabilitation is to be successful. In this context it emphasises the importance of accountable and transparent human services concerned with the human and civil rights of offenders, court diversion schemes, alternatives to custody, and the practical application of restorative and therapeutic justice.
189

Ecology of the forests of south western Australia in relation to climate and landforms.

Jaroslav J Havel January 2000 (has links)
This thesis sets out to test the hypothesis that the vegetational patterns in the forested region of south western Australia are primarily determined by the interaction of climate and landform. The region is an area of 4.25 million hectares subject to recent agreement between the Commonwealth of '4ustralia and the state of Western Australia regarding long-term protection and management of forest (Regional Forest Agreement). The climate of the South Western forest region is warm temperate and summer dry, matching Koeppen's category Cs, usually described as mediterranean. The dominant geological features of South Western Australia are crystalline and sedimentary plateaus and coastal plains. They are subject to a complex process of weathering, denudation and re-deposition, which is the key determinant of landforms and soil patterns. Deep but infertile soils are prevalent. The dominant vegetation formation of the region is open forest, which reduces to woodland in the drier north and east and increases to tall open forest in the moister south. Floristically the vegetation is very rich, comprising over 3000 vascular plant species. The richness resides in the forest and woodland understorey and in the shrublands, heathlands and sedgelands of edaphically extreme sites. By comparison, the forest overstorey is very simple, only one or two species being often dominant over extensive areas. The validation of the hypothesis that climate and landforms determine the vegetation patterns in South Western Australia is carried out in the following stages: 1) review of past studies of vegetation patterns in relation to the underlying environmental factors, relating them to one another in terms of floristics, 2) conversion of landform and climate maps for the region into vegetation maps by means of toposequences, that is gradients of topography, soils and vegetation within individual landform/climate combinations, 3) production of two sets of vegetation maps, namely six maps of vegetation complexes (1:250,000) and one map of vegetation systems (1:500,000), 4) testing the predictive capability of the resulting maps by comparing the occurrences of individual species of trees, shrubs and herbs predicted by map legends, with their records in FloraBase, the geographic information system of the Western Australian Herbarium, and 5) using the outcomes of the above studies to assess the validity of the hypothesis. Because the above hypothesis is so broad, it will be considered under seven headings: a) nature of the vegetation patterns (continuum or discrete categories), b) regional effect of climate and local effect of landform, c) effect of landforms on soil depth, texture and fertility, d) joint effect of slope, soil depth and texture on water balance, e) interactive effect of landform and climate on vegetation patterns, f) response of individual species to climate and landform, and g) effect of other factors of environment, such as fire, on vegetation patterns. The subsidiary hypotheses are defined in Chapter 5. It is concluded that the vegetation of the region forms a lumpy continuum from the wet south west to the dry north east. Within that broad continuum there are localised continua from waterlogged sites in depressions to drought-prone sites on steep stony slopes. However, the dominant vegetation of the region is open forest on plateau uplands with deep infertile soils. Although climate and landforms have a strong effect on vegetation patterns, they do not determine all vegetation patterns directly. Some tree species have ranges of occurrence that are too broad for that, and others have ranges that are too restricted. A more probable explanation is that climate and landforms, together with fire, set the stage on which the interplay of species takes place and determines the structure and composition of the vegetation. An attempt is made to predict the likely effect of climatic changes on vegetation patterns. The applicability of the methodology developed to the mapping of other regions, especially the adjacent ones, is examined. A review is made of how the products of the study, in particular the maps, are currently being used, and suggestions are made how they could be used in the future.
190

Age compositions, growth rates, reproductive biology and diets of the black bream Acanthopagrus butcheri in four estuaries and a coastal saline lake in south-western Australia

G A Sarre January 1999 (has links)
The aims of the studies undertaken for this thesis on the black bream Acanthopagrus butcheri, a species which is confined to estuaries, were to determine the following. (1) The age compositions, growth rates, reproductive biology and diets of the populations of this species in four different estuaries (Swan River, Moore River, NomaluplWalpole and Wellstead estuaries) and a landlocked saline lake (Lake Clifton) and (2) the seasonal and regional distributions of this species within one estuary (Swan River Estuary). Acanthopagrus butcheri were collected at regular intervals from nearshore, shallow (< 2 m) and offshore, deeper (> 2.5 m) waters of the permanently open Swan River Estuary and intermittently open Moore River Estuary on the lower west coast of Australia and from the permanently open Nomalup/Walpole Estuary and normally closed Wellstead Estuary on the southern coast of Western Australia. One hundred A. butcheri were also obtained from a landlocked, coastal saline lake (Lake Clifton), 90 km south of the Swan River Estuary. Sampling employed seine nets, composite gill nets and rod and line. In the Swan River Estuary, black bream typically occur in the saline reaches of the tributary rivers which constitute the upper estuary. However, during heavy freshwater discharge in winter, many individuals are swept downstream into the basins that constitute the middle estuary. These fish migrate back into the upper estuary in spring and the larger fish spawn in this region between the middle of spring and early summer. Although smaller fish tend to remain in the upper estuary during summer as salinities increase, the larger fish migrate further upstream where salinities are lower. The salinities in which A. butcheri spawned in the different systems ranged from as low as 5.5 - 6.8 %CJin the Moore River Estuary to as high as 40.7 - 45.2 %O in the Wellstead Estuary. The use of marginal increment analyses demonstrated that the opaque zones revealed in otoliths by sectioning are formed annually and could thus be used for ageing individual fish and that the opaque zones visible in whole otoliths prior to sectioning could be used for ageing fish up to six years old. The number of annuli on scales did not provide a reliable estimate of age. The structure of the age compositions in the four estuaries varied, presumably reflecting differences in fishing pressure and, in one case, the lack of recruitment in some years. The growth rates of A. butcheri in the four estuaries and landlocked lake differed, which is probably related to variations in one or more of the following; water temperature, density of fish, salinity and the type of food available. The monthly trends exhibited by gonadosomatic indices and the prevalence of different gonadal maturity stages and mature oocytes demonstrate that spawning typically occurs in spring and early summer. The frequent occurrence of yolk vesicle, yolk granule oocytes and post-ovulatory follicles in the ovaries of some mature fish provides strong circumstantial evidence that A. butcheri is a multiple spawner, i.e. spawns more than once during each breeding season. Estimates of the minimum total fecundity ranged between 9.07 x lo4 and 7.09 x lo6, with a mean of 1.58 x lo6. Variations amongst the lengths and ages at first maturity in three of the estuarine populations of A. butcheri could apparently be attributed to the influence of variations in growth rate. Female and male Acanthopagrus butcheri both possess an ovotestis, a feature characteristic of the Sparidae. There is strong circumstantial evidence that, once a member of this species reaches maturity, it can be considered a rudimentary hermaphrodite, i.e. it possesses either functional ovaries and far smaller and immature testes or functional testes and immature ovaries of variable size. There was no evidence that this species undergoes either a protogynous or protandrous sex change. Acanthopagrus butcheri can consume various benthic and epibenthic prey, including crustaceans, polychaetes, molluscs and teleosts, and can also ingest considerable volumes of algae. However, the dietary compositions of A. butcheri in the four estuaries and Lake Clifton differed markedly, whch, together with information on the biota in those systems, indicate that A. butcheri feeds on those prey items that are most abundant in their environment. Yet, there is also evidence that, in any given system, A. butcheri will focus on a particular prey, even when other prey, which are regularly consumed in considerable volume in other systems, are abundant. The dietary compositions of A. butcheri in each estuary underwent ontogenetic changes, which would reduce the potential for intraspecific competition for food resources.

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