Dissertations / Theses on the topic 'Southeast Australia'

To see the other types of publications on this topic, follow the link: Southeast Australia.

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Southeast Australia.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Finlay, Christine School of Sociology &amp Anthropology UNSW. "Smokescreen : black/white/male/female bravery and southeast Australian bushfires." Awarded by:University of New South Wales. School of Sociology and Anthropology, 2005. http://handle.unsw.edu.au/1959.4/23006.

Full text
Abstract:
Black/white/male/female struggles over knowledge correctness and who is brave are examined inductively in the field of bushfires. The paradoxes of a white male icon are linked to contradictions in gender theories in disaster. In mainstream literature, assumptions of innate white male superiority in bravery justify white women???s diminution and white male domination. In feminist theory, women???s diminution is the problem and their bravery for struggling against hegemony applauded. Philosophies of bravery are explored in 104 semistructured interviews and 12 months??? fieldwork as a volunteer bushfirefighter. There is great variety in the ways volunteers cope with bushfires. However, evidence of white male hegemony emerges when volunteers complain of state and territory indifference to preventing property and environmental damage and injury and death. Evidence is examined that Indigenous Australians once managed bushfires better than a sprawl of bureaucracy. Bushfire service claims that Aborigines knew nothing about hazard reductions are contradicted. This debate over bushfire management leads to the discovery of a third epistemology breaking with claims of white male iconic bravery and bureaucratic mastery. To generalise about the habitus of claims to knowledge and bravery, I analyse Newcastle Herald articles from 1881-1981. Three competing knowledge fields and their associated struggles are examined; Indigenous Australians and white womens??? emancipatory struggles confront data on bushfirefighting. Bushfires emerge as a serious problem, a bureaucratic power base and a white male icon from the 1920s.
APA, Harvard, Vancouver, ISO, and other styles
2

Mazumder, Debashish, and res cand@acu edu au. "Contribution of Saltmarsh to Temperate Estuarine Fish in Southeast Australia." Australian Catholic University. School of Arts and Science (NSW, 2004. http://dlibrary.acu.edu.au/digitaltheses/public/adt-acuvp47.09042006.

Full text
Abstract:
Saltmarsh is an important coastal habitat located in the littoral zone of estuaries. Australian saltmarsh area is decreasing due to agricultural and urban development and invasion by mangrove. The aim of the study was to assess the contribution made by saltmarsh as a habitat and a source of food items for fish. Three saltmarsh sites were studied, with Towra Point chosen as a site for detailed ecological study. When corrected for water volume, fish densities were found to be higher within the saltmarsh compared to the adjacent mangrove. Although the fish assemblages in saltmarshes differed significantly from mangroves the overall ratio between commercially and ecologically valuable species in these habitats are similar, a result suggesting the importance of temperate saltmarsh as habitat for economically important fish. Significant export of crab larva from saltmarsh (average crab larval abundance 2124.63 m-3 outgoing water) is a positive contribution to the estuarine food chain supplementing the nutritional requirements of estuarine fish. While the diet of the crabs producing this larvae seems dependant on the saltmarsh environment (given the contrasting isotopic signatures of Sesarma erythrodactyla in saltmarsh and mangrove, and the similarity of isotopic signatures in the saltmarsh for Sesarma erythrodactyla and Helograpsus haswellianus), the crabs do not seem to be dependent on any of the common species of saltmarsh plant, but rather depend on particulate organic matter (POM) derived from local and other sources. Crab larva are a prey item for many estuarine fish, including commercially important species, as evidenced by gut content analysis of fish visiting the saltmarsh flats during spring tides. The results strongly suggest that emphasis be given to ecosystembased management for an estuary rather than component (e.g., vegetation) based managed as defined by the Fisheries Management Act (1994) and the State Environmental Planning Policy 14.
APA, Harvard, Vancouver, ISO, and other styles
3

Bush, Angela L. "Physical and chemical hydrogeology of the Otway Basin, southeast Australia." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/8523.

Full text
Abstract:
The Otway Basin of southeast Australia is the subject of this thesis, which incorporates pre-existing geological, hydraulic and major element hydrogeological data with new isotope hydrogeochemical investigations. The region is an Upper Cretaceous–Tertiary basin, filled with siliciclastic and calcareous aquifers and aquitards and characterised by late volcanic activity, pervasive faulting and karstification. (For complete abstract open document.)
APA, Harvard, Vancouver, ISO, and other styles
4

Mazumder, Debashish. "Contribution of saltmarsh to temperate estuarine fish in southeast Australia." Thesis, Australian Catholic University, 2004. https://acuresearchbank.acu.edu.au/download/6dbd534f7861bacf0f59f392d1b2ecd75f2b50b02048bebf8d84fcf60b2ca640/1902051/64981_downloaded_stream_206.pdf.

Full text
Abstract:
Saltmarsh is an important coastal habitat located in the littoral zone of estuaries. Australian saltmarsh area is decreasing due to agricultural and urban development and invasion by mangrove. The aim of the study was to assess the contribution made by saltmarsh as a habitat and a source of food items for fish. Three saltmarsh sites were studied, with Towra Point chosen as a site for detailed ecological study. When corrected for water volume, fish densities were found to be higher within the saltmarsh compared to the adjacent mangrove. Although the fish assemblages in saltmarshes differed significantly from mangroves the overall ratio between commercially and ecologically valuable species in these habitats are similar, a result suggesting the importance of temperate saltmarsh as habitat for economically important fish. Significant export of crab larva from saltmarsh (average crab larval abundance 2124.63 m-3 outgoing water) is a positive contribution to the estuarine food chain supplementing the nutritional requirements of estuarine fish. While the diet of the crabs producing this larvae seems dependant on the saltmarsh environment (given the contrasting isotopic signatures of Sesarma erythrodactyla in saltmarsh and mangrove, and the similarity of isotopic signatures in the saltmarsh for Sesarma erythrodactyla and Helograpsus haswellianus), the crabs do not seem to be dependent on any of the common species of saltmarsh plant, but rather depend on particulate organic matter (POM) derived from local and other sources. Crab larva are a prey item for many estuarine fish, including commercially important species, as evidenced by gut content analysis of fish visiting the saltmarsh flats during spring tides. The results strongly suggest that emphasis be given to ecosystembased management for an estuary rather than component (e.g., vegetation) based managed as defined by the Fisheries Management Act (1994) and the State Environmental Planning Policy 14.
APA, Harvard, Vancouver, ISO, and other styles
5

Farrelly, Michael. "State, society and water management in late imperial Southeast China." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123264.

Full text
Abstract:
This thesis is a study of water management systems in the late imperial (1368-­‐1912) Minnan region (southern Fujian), China. Based on stone inscriptions and local gazetteers, I present case histories of several well-­‐documented water management systems. I explore trends in social organization and state-­‐society issues relevant to water management systems, with particular emphasis placed upon the means by which lineages came to control water management structures. I then consider the causes and characteristics of water management-­‐related conflict, as well as trends in government intervention in related disputes, and the principles upon which local officials adjudicated these disputes. I argue that property rights status was important to adjudication, particularly the concepts of "official," "communal" and "private" land and resources. Finally, I contextualize Minnan water management systems among systems in other parts of China.
Cette thèse étudie les systèmes de gestion de l'eau pendant les dernières années de la période impériale dans la région de Minnan (dans le sud du Fujian) en Chine. L'histoire de plusieurs systèmes bien documentés de gestion de l'eau est présentée, à partir de l'étude de pierres avec des inscriptions et de registres locaux. Les tendances dans l'organisation sociale liée aux systèmes de gestion de l'eau et les problèmes politico-­‐sociaux associés sont analysés, avec une attention toute particulière sur les moyens employés par les groupes pour contrôler les organisations qui gèrent l'eau. Les causes et les caractéristiques des conflits relatifs à la gestion de l'eau sont étudiées, ainsi que l'intervention des gouvernements et les principes suivis par les instances locales dans la résolution de ces disputes. Les auteurs soutiennent que le statut de la propriété importe dans l'attribution des ressources, en particulier les concepts de ressources « gouvernementales », « communales » et « privées ». En dernière partie, les systèmes de gestion de l'eau dans la région de Minnan sont mis en perspective avec les systèmes d'autres régions de la Chine.
APA, Harvard, Vancouver, ISO, and other styles
6

Rollinson, Daniel J., and n/a. "Synanthropy of the Australian Magpie: A Comparison of Populations in Rural and Suburban Areas of Southeast Queensland, Australia." Griffith University. Australian School of Environmental Studies, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040924.152124.

Full text
Abstract:
The urbanised environment provides ecologists with unique situations in which to undertake ecological study. It has been said that urbanisation is like a natural experiment; we often have populations of animals that have gone from living in natural or semi-natural environments to living in a highly modified anthropogenic environment. These situations provide ideal settings to study the ecological and behavioural differences that may develop in populations located in different habitats. Urbanisation typically results in a minority of species dominating the fauna, and this thesis aimed to examine one such species, the Australian magpie. Despite the magpie being a common and well-liked suburban bird, the majority of previous research on this species has been undertaken within rural or exurban locations. This thesis aimed to examine what actually happens to the species when it lives in the suburban environment. In particular I focused on specific behavioural and ecological features, to see if there were any particular adaptations the suburban magpies showed and also if the suburban habitats provide certain resources favourable to the magpies and what ecological effects these may have. Comparisons of the territory structure and resources of rural and suburban magpies showed that although many features of the territory are similar between rural and suburban locations, notably the choice of native nest trees, magpie territories within suburban areas were smaller and contained more anthropogenic features. The reduced territory size may possibly be related to a greater abundance of key food resources also evident within suburban areas. Furthermore, suburban magpies are more successful in their foraging attempts, again possibly reflecting a more abundant food supply in suburbia and also the simplified nature of suburban foraging areas might facilitate more successful foraging. The increased foraging success is likely to explain the greater provisioning rate to nestling suburban magpies. Suburban magpies also utilised human provided foods. I quantified the extent of wildlife feeding within many of the suburban study sites of this thesis (through the use of questionnaire surveys). In each of the locations it was evident that at least one person (usually more) was providing a regular supply of food to wildlife and magpies appeared to be the main recipients of this food. Previous ecological studies suggest the provision of extra food to avian populations is likely to affect the breeding ecology, and this was so for magpies. The suburban populations initiated breeding significantly earlier than rural magpies. To test the influence of food, supplementary food was provided to rural magpies, not currently receiving any additional human provided foods. The fed rural magpies initiated breeding before control rural magpies (i.e. not receiving any additional food) but suburban magpies still initiated breeding before all other groups. This suggests additional factors present within suburbia, such as warmer temperatures, may also control the timing of breeding in magpies. Magpies in rural and suburban locations lived within different vertebrate communities. Within suburban magpie territories a greater number of intrusions were made by domestic animals, notably dogs (Canis lupus) and cats (Felis domesticus). The frequency of raptors entering the territorial areas occupied by magpies appears to suggest such events are more common in rural areas. The number of humans entering magpie territories was obviously greater in the more populated suburban areas and the majority of magpies responded neutrally to humans. However a group of magpies that previously exhibited extreme aggression towards humans were found to have a greater frequency of aggressive interactions with potential predatory intruders, which were primarily humans. Subsequent examination of the level of corticosterone from this aggressive group of magpies found that a high level of aggressive interactions with potential predators and humans is reflected in higher level of corticosterone, which may have implications for further behavioural and even physiological changes. An ability to habituate to human in urbanised areas is a key attribute of successful synanthropic species. Comparisons of magpies disturbance distances at different points along the urban gradient (the gradient that runs from the urbaised city to natural wildlands) found suburban magpies only responded to humans when they had approached to a close distance (often less than one metre) and many simply walked away to avoid the approaching human. Rural and exurban magpies responded to humans at greater distances than suburban magpies. The distance at which they responded to the human was usually 100 meters plus, and these magpies always flew away. A continuation of this investigation over a temporal scale again found the large difference in response to humans, with suburban magpies exhibiting a decreased response towards humans. However, a certain proportion of responses from suburban magpies were also aggressive. The examination of disturbance distance over the breeding season found that in suburban magpies the responses of most disturbance distance variables remained similar between breeding stages. Rural magpies, however, exhibited variation in their responses towards humans depending on the stage of breeding. It is suggested that the response of rural magpies may be a typical fear response towards an unusual potential threat. The studies presented in this thesis show that magpies have the behavioural capacity to take advantage of resources in suburban landscapes that are not available or are in lessor supply in rural landscapes, it is these abilities that facilitate the magpies synanthropy.
APA, Harvard, Vancouver, ISO, and other styles
7

Rollinson, Daniel J. "Synanthropy of the Australian magpie a comparison of populations in rural and suburban areas of southeast Queensland, Australia /." Connect to this title online, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040924.152124/.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Le, Vy Kim Thi. "Understanding the operational structure of Southeast Asian drug trafficking groups in Australia." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/60670/3/60670.pdf.

Full text
Abstract:
This thesis examined the operational structure of Southeast Asian drug trafficking groups operating on the eastern seaboard of Australia by testing the validity and application of organised crime and drug trafficking typologies using data obtained from 159 drug trafficking cases in three Australian states: New South Wales; Queensland; and Victoria. Key findings indicated that the usefulness of typologies is limited when classifying and analysing organised crime groups. In particular, Southeast Asian drug trafficking groups operated largely in small, informal, family-based hierarchies or groups that were better conceptualised using theoretical perspectives from network and cultural studies. The study recommended that replicating previous empirical research in the field is an effective approach that will contribute towards building a cumulative body of knowledge on organised crime structures.
APA, Harvard, Vancouver, ISO, and other styles
9

Jenkinson, Suzanne Marie. "The conservation value of small wetlands for waterbirds in the southeast of South Australia /." Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09AR/09arj521.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Brieze, Ilze. "Behavioural ecology of bottlenose dolphins (Tursiops sp.) and interactions with humans in Southeast Queensland, Australia /." [St. Lucia, Qld.], 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17014.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
11

Coppa, Isabel Patricia Maria, and Isabel coppa@csw com au. "The use of remote sensing data for broad acre grain crop monitoring in Southeast Australia." RMIT University. Mathematical and Geospatial Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070201.095831.

Full text
Abstract:
In 2025, there will be almost 8 billion people to feed as the worlds population rapidly increases. To meet domestic and export demands, Australian grain productivity needs to approximately triple in the next 20 years, and this production needs to occur in an environmentally sustainable manner. The advent of Hi-tech Precision Farming in Australia has shown promise in recent time to optimize the use of resources. Most
APA, Harvard, Vancouver, ISO, and other styles
12

Switzer, Adam D. "Depositional characteristics of recent and late Holocene overwash sandsheets in coastal embayments from southeast Australia." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20051202.112948/index.html.

Full text
APA, Harvard, Vancouver, ISO, and other styles
13

Pethybridge, Heidi. "Ecology and physiology of deepwater chondrichthyans off southeast Australia : mercury, stable isotope and lipid analysis." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14050/document.

Full text
Abstract:
La gestion et la conservation des pêcheries sont problématiques pour la plupart des chondrichthiens; cela tient principalement au manque de données scientifiques causé par les défis logistiques impliqués par les prélèvements par grandes profondeurs. De plus, plusieurs les techniques analytiques, à l’exemple du contenu stomacal et des mesures morphologiques, demandent des quantités d’échantillons importantes difficilement obtenues. De nouvelles techniques exigent moins d'échantillons, en particulier celles mettant en oeuvre la biochimie qui sont de plus en plus utilisées pour résoudre des questions écologiques et biologiques complexes au niveau individuel et démographique des populations. Cette thèse a testé plusieurs techniques biochimiques (analyses de lipide, mercure, et isotope de carbone et azote) pour mieux comprendre les aspects de la reproduction, de l'écologie trophique, de l'amplification du mercure et de la physiologie de chondrichthiens des profondeurs. La plupart des espèces font partie de l'Ordre des Squaliformes. D'autres espèces appartiennent à différentes Familles: Chimaeridae, Rhinochimaeridae, Scyliorhinidae et Hexanchidae. Tous les échantillons ont été capturés dans les filets de pêcheurs dans les eaux du plateau continental et des marges du sud-est de l'Australie. L’analyse de la composition en lipides de différents tissus révèlent que le foie des chondrichthiens est riche en lipides (38 à 70% de la masse des tissus humides), en majeure partie des lipides neutres et des acides gras mono-saturés. Le foie est un tissu multifonctionnel, qui joue un rôle essentiel dans la distribution de la biosynthèse lipidique, le stockage de l’énergie et la régulation de la flottaison. A l’inverse, le tissu musculaire est un organe structurel, à faible concentration en lipide (<2 %) qui se compose essentiellement de lipides polaires. La composition des lipides rénaux et pancréatiques montre que leur fonctionnement métabolique est complexe. L'analyse des lipides des organes reproducteurs a révélé que l’énergie utile à la gestation chez les adultes chondrichthiens en pré-ovulation nécessite un pourcentage important de lipide (follicule ovarien 18 à 34 %). Les variations de triacylglycérols (8 à 48 %), des éthers diacylglycéryls (0,2 à 28 %) et des cires (0,5 à 20 %) ont été observées dans tous les échantillons. Ces variations impliquent l'utilisation de classes lipidiques multiples pour favoriser le développement embryonnaire. Les réserves maternelles sont différentes entre espèces ovipares et vivipares et entre les élasmobranches et les holocéphales. L’allocation la plus important de lipides est trouvée chez les requins vivant dans les environnements les plus profonds. Cette observation suggère que leur fécondité est plus faible et que leur vulnérabilité face à la pêche est plus importante. Le régime alimentaire des requins a été déterminé par des techniques complémentaires: traceurs lipidiques et analyses du contenu stomacal. 41 taxons de proie ont été identifiés. Ils étaient surtout composés de poissons et de céphalopodes du domaine demersal. En utilisant les profils des acides gras, la variabilité de la composition de nourriture a été établie pour chaque espèce en associant la signature de ces profils dans les tissus des chondrichthiens aux profils de plusieurs proies. Les deux techniques ont montré que les chondrichthiens sont des prédateurs opportunistes qui consomment une large gamme de proie. Les concentrations en mercure et sa distribution des tissus ont été examinés pour accéder à sa bioamplification dans ce type d’organisme et de déterminer des niveaux de contamination pour la consommation publique. Le mercure total (THg : toutes formes chimiques confondues) et le méthylmercure (MeHg : la forme la plus toxique et bioaccumulable) ont été dosées. Pour la plupart des espèces, les niveaux de THg étaient supérieurs au seuil maximal recommandé par les législations en vigueur dans plusieurs pays dont l’Australie (>0,1 mg kg-1 pois humide, ph) et une concentration aussi forte que 6,6 mg kg-1 (ph) a été enregistrée. L'
Analyse de spéciation a montré que le mercure est présent à plus de 91 % sous forme de MeHg, et même avec des taux supérieurs à 95 % chez les espèces des environnements les plus profonds. Les concentrations maximales en THg ont été trouvés dans les tissus musculaires (59 à 82 % de charge corporelle). Les reins et le foie possèdent aussi des taux élevés, respectivement de 0,3 à 4,2 et 0,5 à 1,5 mg kg-1 (ph), tandis que la peau enregistre les concentrations les plus faibles (> 0,3 mg kg-1, ph). Cette étude de l’organotropisme permet de conclure que les reins et le foie sont associés au métabolisme du métal, à l'élimination et au stockage à court terme, alors que le muscle est le sites le plus important du stockage du mercure à long terme. Les isotopes stables de carbone et d’azote ont été utilisés pour évaluer l'influence de la position trophique (d15N) et de la source de carbone (d13C) sur l'accumulation du THg chez les chondrichthiens. Le d15N varie entre 12,4 à 16,6 ‰ démontrant la large gamme de positions trophiques occupées par ces espèces. La variation interspécifique du d13C est quant à elle minimale (–18,7 à –17,1 ‰). Les concentrations en mercure notées chez la plupart des requins augmentent en fonction de la taille, de la position trophique (d15N) et du stade de maturité de l’animal. Dans la communauté des chondrichthiens des profondeurs on observe des taux modérés de bioamplification du mercure, ceci est révélé par la faible pente de la relation, log (THg mg kg-1 ww) = 0,2 (d15N) – 2,4 (R2 = 0,35 ; P <0,05). Le THg et les acides gras de 61 espèces appartenant aux niveaux trophiques intermédiaires ont été analysés dans le but d’étudier les régimes alimentaires des proies et la bioaccumulation de ce métal à travers la chaîne alimentaire démersale. L'utilisation intégrée de ces techniques biochimiques a fourni des données fondamentales sur la reproduction, l'accumulation en mercure et l'écologie trophique des chondrichthiens des profondeurs. La compréhension de ces fonctions est impérative non seulement pour la mise en place d’une gestion durable des pêcheries, mais aussi pour la protection des habitats des chondrichthiens et leurs écosystèmes associés
For most deepwater chondrichthyans, fisheries and conservation management is problematic, largely due to the lack of scientific data resulting from inherent logistical challenges working within deep-sea environments. Furthermore, many conventional analytical techniques (stomach content analysis and morphometrics) require large sample sizes and are often quantitatively inadequate. Thus, new and more robust methods requiring fewer specimens are needed. Biochemical ‘tracer’ techniques are increasingly being used to resolve complex ecological and biological questions at individual species and population levels. This research explored the integrated use of multiple biochemical techniques (lipid and fatty acid profiling, stable nitrogen and carbon isotope and mercury analysis) to understand aspects of the reproduction, feeding ecology, metal accumulation and physiology of deepwater chondrichthyans. Most were from the Order Squaliformes. Other species include those from the Families: Chimaeridae, Rhinochimaeridae, Scyliorhinidae and Hexanchidae. All specimens were caught as fisheries bycatch from the continental slope waters off southeast Australia. The examination of lipid composition and partitioning revealed that deepwater chondrichthyans have large, lipid rich (38–70 % wet weight, ww) livers high in neutral lipids and monounsaturated fatty acids. Liver is a multifunctional tissue, playing a vital role in lipid distribution and biosynthesis, buoyancy regulation and storage. In contrast, muscle is a structural organ, low in lipid (<2 %) and consisting primarily of polar lipids. Lipid composition of kidney and pancreas show that they, too, have complex roles in lipid metabolism and storage. Lipid analysis of reproductive tissues revealed high maternal investment in deepwater chondrichthyans as indicated by high lipid content in mature pre-ovulated ovarian follicles (18–34 %). Variable levels of triacylglycerols (8–48 %), diacylglyceryl ethers (0.2–28 %) and wax esters (0.5–20 %) were observed in all specimens, demonstrating the use of multiple lipid classes to fuel embryonic development. The maternal provisions differed between oviparous and viviparous species and between elasmobranchs and holocephalans. Greater lipid investment was displayed by sharks living in deeper environments, suggesting lower fecundity and increased vulnerability to fishing. Diet was examined by complementary lipid biomarker and traditional stomach content techniques. A total of 41 prey taxa were identified using stomach content analysis and consisted mainly of bathyal-demersal fish and cephalopods. Using multidimensional scaling analysis, the extent of variability in composition within each species was determined by grouping the signature fatty acid profiles of shark tissues with profiles for demersal fish, squid and crustaceans. Both techniques showed that deepwater chondrichthyans are opportunistic predators, and that there is some degree of specialisation and overlap between them. Total (THg) and inorganic (monomethyl, MeHg) mercury concentrations and tissue distribution were examined to determine the extent of biomagnification and evaluate levels for human consumption. Mean THg levels for most species were above the regulatory threshold (>0.1 mg kg-1 ww) and levels as high as 6.6 mg kg-1 ww were recorded. Speciation analysis demonstrated that 91% mercury was bound as MeHg with higher percentages (>95%) observed in species occupying deeper environments. Higher levels of THg were stored in muscle which accounted for between 59–82% of the total body burden of mercury. High levels were also found in kidney (0.3–4.2 mg kg-1 ww) and liver (0.5–1.5) with lower levels observed in skin (>0.3). Both the kidney and liver are likely to be associated in metal metabolism, short term storage and elimination procedures, while the muscle is the major site for long term storage. Stable isotopes were used as natural dietary tracers, to further evaluate dietary relationships and to assess the influence of trophic position (d15N) and carbon sources (d13C) on THg accumu
lation. Isotopic nitrogen (d15N) values ranged from 12.4 to 16.6 ‰ demonstrating a broad range of trophic positions. Minor variation in carbon (d13C) enrichment was observed between species (–18.7 to –17.1‰). In most shark species, mercury concentrations increased with size, trophic position (d15N), and maturity stage, but not between location or collection period. As a community, deepwater sharks demonstrated moderate rates of THg biomagnification, as indicated by the regression slope (log (THg) = 0.2 d15N – 2.4, R2 = 0·35, P < 0·05). THg and fatty acid analyses of 61 mid-trophic species were measured for their usage in studies of diet in high-order predators and mercury bioaccumulation in the extended demersal food chain. The integrated use of these biochemical techniques has provided fundamental data on the reproduction, metal accumulation and trophic ecology of deepwater chondrichthyans. Understanding these parameters is imperative not only for the implementation of sustainable management but for habitat protection of deepwater chondrichthyans and their associated ecosystems
APA, Harvard, Vancouver, ISO, and other styles
14

Pham, Cong Tri. "The ecology of fish larvae in Pumicestone Passage : an estuarine system in Southeast Queensland, Australia /." St. Lucia, Qld, 2000. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16437.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
15

Armstrong, Timothy James. "Determination of aquifer properties and heterogeneity in a large coastal sand mass : Bribie Island, Southeast Queensland." Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16278/1/Timothy_Armstrong_Thesis.pdf.

Full text
Abstract:
Aquifer heterogeneity within the large coastal sand island of Bribie Island, Queensland, Australia, has an affect on groundwater occurrence and migration. The stratigraphy of Bribie Island is complicated by the presence of low permeability humate-cemented indurated sand layers. Occurrences of indurated sand layers have previously been identified within many unconsolidated profiles along the east coast of Australia and around the world. Indurated sand layers are often discontinuous resulting in localised aquifer heterogeneity. However, their regional significance is commonly underestimated. The groundwater resource of Bribie Island is of commercial and environmental significance to the surrounding bay area. Recent development proposals for the groundwater resource necessitate an investigation into the nature of the water bearing properties of the island aquifer and in particular the presence of aquifer heterogeneity. Investigation of a "reference" transect across Bribie Island has involved the drilling and development of monitoring wells and the performance of hydraulic tests. This study demonstrates how detailed measurement of stratigraphy, groundwater levels, rainfall, barometric pressure and hydraulic testing can be used in conjunction to identify and assess aquifer heterogeneity within a sand island environment. Drill logs confirm the position of a palaeochannel within the sandstone bedrock that extends from the mainland continuing under Bribie Island. The overlying sediment profile is thickest within the palaeochannel. The Pleistocene and Holocene unconsolidated profile reflects a prograding barrier island/strandplain formation. The vertical sequence of sediments consists of units that range from offshore sandy silts to foreshore and beach medium-fine grained sands. An extensive indurated sand layer exists throughout the centre of the island. The greatest thickness of indurated sand is located centrally on the island beneath the main beach ridge system. The indurated layer at its thickest is approximately 5-8 m thick, but over much of the island the thickness is 1-3 m. The top of indurated sand layer is generally 1-3 m above mean sea level. Hydrographs from a network of groundwater monitoring wells illustrate that the groundwater resources across the reference transect can be divided into a shallow unconfined water table aquifer and basal confined aquifers. These upper and lower aquifers are characterised by different hydrological processes, physico-chemical properties, and water chemistry. The stratification of water levels across the reference transect and the relatively flat piezometric surface are in contrast with the classical "domed" water table aquifer expected of a barrier island. Stratified head gradients through the Bribie Island aquifers suggest groundwater migration to depth is impeded by the indurated sand layer. An elevated shallow water table results from the mounding of water above the indurated sand layer. The indurated sand layer is extensive across the reference transect. The elevated unconfined groundwater is usually stained with organic matter ("black water"), where as groundwater sourced from beneath the indurated sand layer is colourless ("white water"). The unconfined groundwater is also distinguished by low pH, low bicarbonate concentrations and high concentrations of organic carbon. Interaction between unconfined groundwater and surface water are also evident. Hydraulic tests indicate that each of the unconsolidated units across the reference transect has distinctive hydraulic characteristics. Estimates of vertical and horizontal hydraulic conductivity of the unconfined aquifer are two to three orders of magnitude greater than estimates for the indurated sand layer. Beneath the indurated sand layer hydraulic conductivities of the basal aquifers are also greater by two to three orders of magnitude than estimates for the indurated sand layer. The lower hydraulic conductivity within the indurated sand layer is responsible for the local semiconfinement of the basal aquifers.
APA, Harvard, Vancouver, ISO, and other styles
16

Armstrong, Timothy James. "Determination of aquifer properties and heterogeneity in a large coastal sand mass : Bribie Island, Southeast Queensland." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16278/.

Full text
Abstract:
Aquifer heterogeneity within the large coastal sand island of Bribie Island, Queensland, Australia, has an affect on groundwater occurrence and migration. The stratigraphy of Bribie Island is complicated by the presence of low permeability humate-cemented indurated sand layers. Occurrences of indurated sand layers have previously been identified within many unconsolidated profiles along the east coast of Australia and around the world. Indurated sand layers are often discontinuous resulting in localised aquifer heterogeneity. However, their regional significance is commonly underestimated. The groundwater resource of Bribie Island is of commercial and environmental significance to the surrounding bay area. Recent development proposals for the groundwater resource necessitate an investigation into the nature of the water bearing properties of the island aquifer and in particular the presence of aquifer heterogeneity. Investigation of a "reference" transect across Bribie Island has involved the drilling and development of monitoring wells and the performance of hydraulic tests. This study demonstrates how detailed measurement of stratigraphy, groundwater levels, rainfall, barometric pressure and hydraulic testing can be used in conjunction to identify and assess aquifer heterogeneity within a sand island environment. Drill logs confirm the position of a palaeochannel within the sandstone bedrock that extends from the mainland continuing under Bribie Island. The overlying sediment profile is thickest within the palaeochannel. The Pleistocene and Holocene unconsolidated profile reflects a prograding barrier island/strandplain formation. The vertical sequence of sediments consists of units that range from offshore sandy silts to foreshore and beach medium-fine grained sands. An extensive indurated sand layer exists throughout the centre of the island. The greatest thickness of indurated sand is located centrally on the island beneath the main beach ridge system. The indurated layer at its thickest is approximately 5-8 m thick, but over much of the island the thickness is 1-3 m. The top of indurated sand layer is generally 1-3 m above mean sea level. Hydrographs from a network of groundwater monitoring wells illustrate that the groundwater resources across the reference transect can be divided into a shallow unconfined water table aquifer and basal confined aquifers. These upper and lower aquifers are characterised by different hydrological processes, physico-chemical properties, and water chemistry. The stratification of water levels across the reference transect and the relatively flat piezometric surface are in contrast with the classical "domed" water table aquifer expected of a barrier island. Stratified head gradients through the Bribie Island aquifers suggest groundwater migration to depth is impeded by the indurated sand layer. An elevated shallow water table results from the mounding of water above the indurated sand layer. The indurated sand layer is extensive across the reference transect. The elevated unconfined groundwater is usually stained with organic matter ("black water"), where as groundwater sourced from beneath the indurated sand layer is colourless ("white water"). The unconfined groundwater is also distinguished by low pH, low bicarbonate concentrations and high concentrations of organic carbon. Interaction between unconfined groundwater and surface water are also evident. Hydraulic tests indicate that each of the unconsolidated units across the reference transect has distinctive hydraulic characteristics. Estimates of vertical and horizontal hydraulic conductivity of the unconfined aquifer are two to three orders of magnitude greater than estimates for the indurated sand layer. Beneath the indurated sand layer hydraulic conductivities of the basal aquifers are also greater by two to three orders of magnitude than estimates for the indurated sand layer. The lower hydraulic conductivity within the indurated sand layer is responsible for the local semiconfinement of the basal aquifers.
APA, Harvard, Vancouver, ISO, and other styles
17

Sloss, Craig R. "Holocene sea-level change and the aminostratigraphy of wave-dominated barriers estuaries on the southeast coast of Australia." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060306.154507/index.html.

Full text
APA, Harvard, Vancouver, ISO, and other styles
18

Liaghati, Tania. "Trace metal geochemistry and weathering mineralogy in a quaternary coastal plain, Bells Creek catchment, Pumicestone Passage, Southeast Queensland, Australia." Thesis, Queensland University of Technology, 2004. https://eprints.qut.edu.au/15998/1/Tania_Liaghati_Thesis.pdf.

Full text
Abstract:
The Bells Creek catchment covers an area of 100 km2 in the northern part of the Pumicestone Passage region of southeast Queensland. This catchment is an example of a low-lying sub-tropical coastal plain including both freshwater and estuarine settings. The main creeks drain into Pumicestone Passage, a large shallow estuary, which is a declared marine habitat and a Ramsar listed wading bird location. The Bells Creek catchment has undergone land-use change from bushland to grazing to pine plantations and is now coming under pressure for urban development. Quaternary age unconsolidated sediments are the dominant surface material in this area and formed during the last marine transgression. Of significance for such a setting is that estuarine sediments can retain metals mobilised as a result of natural processes (e.g. weathering) and anthropogenic activities (e.g. land-use disturbance). As trace metals can also occur naturally in rocks and their weathered products, it is of value to clearly distinguish natural and anthropogenic controls over metal source, distribution and mobility. To achieve this aim two approaches were taken: 1) to determine the factors controlling the geochemistry of weathered profiles, unconsolidated sediments, soils and natural waters, and 2) to identify the most effective analytical and numerical methods for evaluating metal concentration in different solid materials. This investigation is structured around four linked papers. The influence of mineralogy, geological setting, location of water table and depth of burial on the geochemistry of weathered profile are assessed in Paper 1. The second paper is an investigation of different analytical approaches for studying weathered sedimentary rocks, as well as the testing of several numerical methods for evaluating geochemical data from weathered profiles. In paper 3, a large heterogeneous geochemical data set including trace metals, total organic carbon and sulfur content, in addition to mineralogy and land use practices are integrated to enable evaluation of geochemical and anthropogenic processes controlling metal distribution. The fourth paper considers the distribution of iron and its transport as well as variations in size and morphology of different forms of framboidal pyrite within a smaller sub-catchment in the southern part of the study area. The labile and heterogeneous nature of the bedrock of the region, the Landsborough Sandstone, along with the sub-tropical climate of the area have resulted in weathering profiles up to 26 m deep. Due to the absence of industrial activity in the Bells Creek catchment, such weathering of the bedrock constitutes the major process governing metal distribution throughout the area. Analysis by X-ray diffraction (XRD) shows that the primary minerals occurring in the weathered profiles are quartz, plagioclase and K-feldspars while kaolinite is the most dominant secondary mineral present. Overall, parent rock silicates have been extensively replaced by clay minerals and Fe oxides. The relative influence of mineralogy, geological setting and groundwater over chemical weathering and geochemical cycling of metals can be summarised as follows: Mineralogy>geological setting>watertable position>depth of profile burial As the relationship between the total metal composition and the extractable and mobile component has environmental significance, a comparison was made between these forms of metals in weathered material. This comparison shows that metals such as V, Cr and Fe are part of the aluminosilicate matrix and remain largely in primary mineral structures. The retention of these metals may lead to their future release to the environment during on-going weathering. Other elements such as Cu, Zn, Pb, however, are found to be primarily adsorbed to sediment particles and therefore, easily releasable to the environment. As limited information on weathering of sedimentary rocks is reported in the literature, a variety of chemical analysis and numerical assessment methods were used to understand the geochemical processes involved in trace metal mobility in the weathered profiles. Two analytical methods of digestion, hydrofluoric acid and x-ray fluorescence were tested and found to be highly comparable except for refractory elements such as V and Cr. Among the numerical methods applied to the dataset were "chemical and mineralogical indices", "weight loss factor" and "immobile element approach". The "immobile element approach" was found to be the most appropriate method to characterise the weathering profiles typical of the catchment. This method considers a weathering system to be open and transforms the absolute values of trace metals enabling a quantitative evaluation of metal mobility. The following sequence of mobility was determined after applying this method to the data generated in this study: Zn>Pb>Cu>Cr>V The above sequence of mobility is supported by the comparison between extractable and total metal concentrations where Cr and V were identified as being part of aluminosilicate matrix and less mobile. On the other hand, Zn, Pb and Cu were found to exist in adsorbed form and to be readily released to the environment. Trace elements released through weathering and erosion of the bedrock can accumulate in estuarine and coastal sediments. Therefore, both the lateral and vertical distribution of trace metals within sediments and soils of Bells Creek catchment were investigated. Natural and anthropogenic factors controlling metal distribution were compared and it was concluded that the natural sediment character such as its mineral content is more significant than anthropogenic influences in controlling lateral and vertical metal distribution. Further, due to varying degrees of weathering and the heterogeneous nature of soils and sediments, the data were normalised. After testing several methods, it was concluded that calculation of an enrichment factor was the most appropriate. The enrichment factor revealed that elevated trace metal concentrations at some sites are due to bedrock weathering. Due to the environmental persistence of iron, excess of this common metal has always been of environmental concern in many coastal settings. In the small Halls Creek sub-catchment, for example, iron anomalies were detected in bottom sediments (Fe up to 14%). This finding has significance in the area, as iron has been identified as one of the major contributors in the growth of the toxic cyanobacteria "Lyngbya majuscula" which can negatively impact on aquatic fauna. Iron concentrations were also shown to be high in natural stream waters of this coastal zone (up to 16 mg/L); in the bottom sediments of the creek, iron occurs as hematite (freshwater section) or pyrite (estuarine section). A variety of pyrite morphologies were identified in both bottom sediments and particulate matter samples including spherical closely packed framboids, and the rare form of euhedra which indicates slow crystallisation. The different components of this investigation have: 1) established the order and extent to which natural factors control weathering, 2) tested a number of analytical and numerical methods in evaluating weathering profiles, 3) assessed natural and anthropogenic factors and established the mobility sequence for trace metals in weathered profiles and, 4) determined the iron mineral speciation and established morphological variations of pyrite. As the area of Bells Creek catchment will be under development pressure in the future, findings of this study represent a baseline of comparison for environmental assessment and are of importance for environmental management.
APA, Harvard, Vancouver, ISO, and other styles
19

Liaghati, Tania. "Trace metal geochemistry and weathering mineralogy in a quaternary coastal plain, Bells Creek catchment, Pumicestone Passage, Southeast Queensland, Australia." Queensland University of Technology, 2004. http://eprints.qut.edu.au/15998/.

Full text
Abstract:
The Bells Creek catchment covers an area of 100 km2 in the northern part of the Pumicestone Passage region of southeast Queensland. This catchment is an example of a low-lying sub-tropical coastal plain including both freshwater and estuarine settings. The main creeks drain into Pumicestone Passage, a large shallow estuary, which is a declared marine habitat and a Ramsar listed wading bird location. The Bells Creek catchment has undergone land-use change from bushland to grazing to pine plantations and is now coming under pressure for urban development. Quaternary age unconsolidated sediments are the dominant surface material in this area and formed during the last marine transgression. Of significance for such a setting is that estuarine sediments can retain metals mobilised as a result of natural processes (e.g. weathering) and anthropogenic activities (e.g. land-use disturbance). As trace metals can also occur naturally in rocks and their weathered products, it is of value to clearly distinguish natural and anthropogenic controls over metal source, distribution and mobility. To achieve this aim two approaches were taken: 1) to determine the factors controlling the geochemistry of weathered profiles, unconsolidated sediments, soils and natural waters, and 2) to identify the most effective analytical and numerical methods for evaluating metal concentration in different solid materials. This investigation is structured around four linked papers. The influence of mineralogy, geological setting, location of water table and depth of burial on the geochemistry of weathered profile are assessed in Paper 1. The second paper is an investigation of different analytical approaches for studying weathered sedimentary rocks, as well as the testing of several numerical methods for evaluating geochemical data from weathered profiles. In paper 3, a large heterogeneous geochemical data set including trace metals, total organic carbon and sulfur content, in addition to mineralogy and land use practices are integrated to enable evaluation of geochemical and anthropogenic processes controlling metal distribution. The fourth paper considers the distribution of iron and its transport as well as variations in size and morphology of different forms of framboidal pyrite within a smaller sub-catchment in the southern part of the study area. The labile and heterogeneous nature of the bedrock of the region, the Landsborough Sandstone, along with the sub-tropical climate of the area have resulted in weathering profiles up to 26 m deep. Due to the absence of industrial activity in the Bells Creek catchment, such weathering of the bedrock constitutes the major process governing metal distribution throughout the area. Analysis by X-ray diffraction (XRD) shows that the primary minerals occurring in the weathered profiles are quartz, plagioclase and K-feldspars while kaolinite is the most dominant secondary mineral present. Overall, parent rock silicates have been extensively replaced by clay minerals and Fe oxides. The relative influence of mineralogy, geological setting and groundwater over chemical weathering and geochemical cycling of metals can be summarised as follows: Mineralogy>geological setting>watertable position>depth of profile burial As the relationship between the total metal composition and the extractable and mobile component has environmental significance, a comparison was made between these forms of metals in weathered material. This comparison shows that metals such as V, Cr and Fe are part of the aluminosilicate matrix and remain largely in primary mineral structures. The retention of these metals may lead to their future release to the environment during on-going weathering. Other elements such as Cu, Zn, Pb, however, are found to be primarily adsorbed to sediment particles and therefore, easily releasable to the environment. As limited information on weathering of sedimentary rocks is reported in the literature, a variety of chemical analysis and numerical assessment methods were used to understand the geochemical processes involved in trace metal mobility in the weathered profiles. Two analytical methods of digestion, hydrofluoric acid and x-ray fluorescence were tested and found to be highly comparable except for refractory elements such as V and Cr. Among the numerical methods applied to the dataset were "chemical and mineralogical indices", "weight loss factor" and "immobile element approach". The "immobile element approach" was found to be the most appropriate method to characterise the weathering profiles typical of the catchment. This method considers a weathering system to be open and transforms the absolute values of trace metals enabling a quantitative evaluation of metal mobility. The following sequence of mobility was determined after applying this method to the data generated in this study: Zn>Pb>Cu>Cr>V The above sequence of mobility is supported by the comparison between extractable and total metal concentrations where Cr and V were identified as being part of aluminosilicate matrix and less mobile. On the other hand, Zn, Pb and Cu were found to exist in adsorbed form and to be readily released to the environment. Trace elements released through weathering and erosion of the bedrock can accumulate in estuarine and coastal sediments. Therefore, both the lateral and vertical distribution of trace metals within sediments and soils of Bells Creek catchment were investigated. Natural and anthropogenic factors controlling metal distribution were compared and it was concluded that the natural sediment character such as its mineral content is more significant than anthropogenic influences in controlling lateral and vertical metal distribution. Further, due to varying degrees of weathering and the heterogeneous nature of soils and sediments, the data were normalised. After testing several methods, it was concluded that calculation of an enrichment factor was the most appropriate. The enrichment factor revealed that elevated trace metal concentrations at some sites are due to bedrock weathering. Due to the environmental persistence of iron, excess of this common metal has always been of environmental concern in many coastal settings. In the small Halls Creek sub-catchment, for example, iron anomalies were detected in bottom sediments (Fe up to 14%). This finding has significance in the area, as iron has been identified as one of the major contributors in the growth of the toxic cyanobacteria "Lyngbya majuscula" which can negatively impact on aquatic fauna. Iron concentrations were also shown to be high in natural stream waters of this coastal zone (up to 16 mg/L); in the bottom sediments of the creek, iron occurs as hematite (freshwater section) or pyrite (estuarine section). A variety of pyrite morphologies were identified in both bottom sediments and particulate matter samples including spherical closely packed framboids, and the rare form of euhedra which indicates slow crystallisation. The different components of this investigation have: 1) established the order and extent to which natural factors control weathering, 2) tested a number of analytical and numerical methods in evaluating weathering profiles, 3) assessed natural and anthropogenic factors and established the mobility sequence for trace metals in weathered profiles and, 4) determined the iron mineral speciation and established morphological variations of pyrite. As the area of Bells Creek catchment will be under development pressure in the future, findings of this study represent a baseline of comparison for environmental assessment and are of importance for environmental management.
APA, Harvard, Vancouver, ISO, and other styles
20

So, Thea. "Improving reforestation success of high-value and key forest species by direct seeding in Southeast Asia and Western Australia." Thesis, So, Thea (2011) Improving reforestation success of high-value and key forest species by direct seeding in Southeast Asia and Western Australia. PhD thesis, Murdoch University, 2011. https://researchrepository.murdoch.edu.au/id/eprint/7246/.

Full text
Abstract:
Worldwide, natural forests have been decreasing in area at an alarming rate. In Cambodia, the annual deforestation rate was 127 000 ha year-1 from 2005 to 2010 and this seriously threatens biodiversity and the livelihoods of rural communities. Therefore, there is an urgent need to reforest or establish forest plantations to meet two main objectives: economic development and biodiversity conservation. This thesis concerns the promotion of early survival and growth of planted or direct-seeded seedlings to overcome the harsh conditions of reforestation sites in tropical and mediterranean-type ecosystems, with special attention given to threatened high-value timber species of Southeast Asia. Worldwide, there is an increasing effort to reforest degraded forests and old agricultural lands. However, reforestation of degraded lands is often difficult and is usually expensive; therefore, direct seeding is an alternative to conventional tree planting. Some of the major constraints facing reforestation efforts were reviewed, and opportunities that could be useful for promotion of early establishment and growth of seedlings were explored. These were then used to define reforestation field studies in Australia, Thailand and Cambodia. In a harsh mediterranean-type ecosystem in Western Australia, effects of microorganisms (mycorrhizal fungi and N2-fixing bacteria) and planting material (seed and seedling) on survival and growth of two key post-disturbance colonizing species, Eucalyptus gomphocephala and Acacia saligna, were investigated. For E. gomphocephala, survival at 13 months was higher for out-planted seedlings (81%) than from direct seeding (7.5%). Inoculation with ectomycorrhizal fungal spores was not beneficial. For A. saligna, survival at 13 months was also higher for seedlings (84%) than for seeding (42.5%). Nitrogen-fixing bacteria from crushed root nodules of A. saligna did not promote survival or growth of the species nor did a mixed commercial mycorrhizal inoculum. In Southeast Asia, the leguminaceous rosewoods, Afzelia xylocarpa and Dalbergia cochinchinensis, are threatened throughout their range by habitat loss and over exploitation for their extremely highly-prized timber. The species have been promoted for reforestation in Cambodia for economic development and genetic conservation. The current conservation status of A. xylocarpa and D. cochinchinensis in Cambodia was examined, and information on silviculture, trade and current conservation measures applied in that country was drawn together. Some important steps in the development of domestication strategies, including testing and improving silvicultural practices and increasing the supply of genetically superior seeds from seed production areas and seed orchards, were outlined. This information was then used to help select species for the trials in Thailand and Cambodia. Many high-value timber species of continental Southeast Asia, including some rosewoods, have been promoted in reforestation programmes. However, the slowgrowing habit at the early stage of development is a challenge for promoting these species in tree plantings. Therefore, effects of beneficial microorganisms and fertilizer on establishment and growth of direct-seeded seedlings of D. cochinchinensis and Xylia xylocarpa were investigated in a trial on former agroforestry land in Thailand and compared to Acacia mangium, an exotic fast-growing plantation species. After 20 months, a mixed inoculum of arbuscular mycorrhizal (AM) + ectomycorrhizal (ECM) fungi and a mixed inoculum of AM fungi + N2-fixing bacteria (crushed root nodule) improved survival of D. cochinchinensis by 15 and 17%, respectively. The co-inoculation of AM with ECM also improved diameter growth of the same species by 43%. A second field trial explored the effects a water retention polymer and fertilizer on direct seeding of A. mangium, Afzelia xylocarpa, D. cochinchinensis, Eucalyptus camaldulensis, Sindora cochinchinensis and X. xylocarpa. The combination of polymer and fertilizer increased height growth of all six tree species by 40%. The effect of the polymer and fertilizer was further investigated in Cambodia with direct seeding of the same indigenous species. There, the combination of the polymer with fertilizer increased seedling establishment only by 7%. As selected strains of compatible N2-fixing bacteria were not available, crushed root nodules were used in some of the field trials. In order to improve the technology in the future, three strains of N2-fixing bacteria were isolated from root nodules of D. cochinchinensis grown in Cambodia and then tested under glasshouse conditions and a seed coating technique was employed as a means to deliver bacteria to seeds along with broth culture. After 16 weeks, one of the three isolates increased total dry weight of D. cochinchinensis seedlings by ca. 150% over the uninoculated control that was not fed inorganic nitrogen. The effective strain was identified as Bradyrhizobium elkanii after the DNA was amplified by polymerase chain reaction using RPO1 primer (5'-AAT TTT CAA GCG TCG TGC CA-3') and then partial 16S rRNA nucleotide gene sequences were compared with the Gene Bank database. Both methods of delivering of bacteria (seed coating and broth culture) were equally effective. The effectiveness of B. elkanii was explored under field conditions in Cambodia with direct seeding of D. cochinchinensis, but no effect on seedling establishment or growth was obtained after six months of trial establishment. Competition from indigenous bacteria was suggested as one of the reasons for the ineffectiveness of the introduced strain. The main finding of this thesis was the suitability of the four high-value timber species in reforestation by direct seeding in tropical regions, in former agricultural land where proper site preparation and intensive weeding were provided, as well as on land previously under degraded forest where minimal site preparation was undertaken. Also, the application of a water retention polymer promoted establishment and growth of seedlings under tropical conditions. This should be evaluated further in a wider range of reforestation sites including sandy soils. More work should be undertaken to identify effective symbionts for the tropical rosewoods. These and other symbionts should be evaluated in reforestation trials in which more attention is paid to site characteristics and populations of indigenous beneficial organisms.
APA, Harvard, Vancouver, ISO, and other styles
21

Jess, Gabrielle M. "Minding my own business: Small business owners' decision making during a response to a natural disaster in southeast Queensland, Australia." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/228750/1/Gabrielle_Jess_Thesis.pdf.

Full text
Abstract:
With Australia experiencing unprecedented natural disasters, this transdisciplinary thesis is timely. It explores small business owner’s decision making during such events in Southeast Queensland alongside the affordances provided by public and non-profit entities to sustain business continuity. Using interview data of business owners’ and key informants’ from urban, peri-urban and rural communities, this study catalogued their decisions, decision processes and affordances organised around six business capitals. As predicted by the recognition primed decision theory, decisions were quick yet indicated both complexities and competencies of business owners. Fast decisions and political affordances support business owners’ survival during high consequence, disruptive events.
APA, Harvard, Vancouver, ISO, and other styles
22

Broinowski, Alison Elizabeth, and alison broinowski@anu edu au. "About face : Asian representations of Australia." The Australian National University. Faculty of Asian Studies, 2002. http://thesis.anu.edu.au./public/adt-ANU20030404.135751.

Full text
Abstract:
This thesis considers the ways in which Australia has been publicly represented in ten Asian societies in the twentieth century. It shows how these representations are at odds with Australian opinion leaders’ assertions about being a multicultural society, with their claims about engagement with Asia, and with their understanding of what is ‘typically’ Australian. It reviews the emergence and development of Asian regionalism in the twentieth century, and considers how Occidentalist strategies have come to be used to exclude and marginalise Australia. A historical survey outlines the origins of representations of Australia in each of the ten Asian countries, detecting the enduring influence both of past perceptions and of the interests of each country’s opinion leaders. Three test cases evaluate these findings in the light of events in the late twentieth century: the first considers the response in the region to the One Nation party, the second compares that with opinion leaders’ reaction to the crisis in East Timor; and the third presents a synthesis of recent Asian Australian fiction and what it reveals about Asian representations of Australia from inside Australian society. The thesis concludes that Australian policies and practices enable opinion leaders in the ten countries to construct representations of Australia in accordance with their own priorities and concerns, and in response to their agendas of Occidentalism, racism, and regionalism.
APA, Harvard, Vancouver, ISO, and other styles
23

Feng, Yuexing. "40Ar/39Ar dating of young supergene Mn-Oxides : implication for late Cainozoic weathering history and landscape evolution, Mary Valley, Southeast Queensland, Australia /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19080.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
24

Wang, Qing. "Impacts of climate, topography, and weathering profile on vadose zone hydrology and coastal pine plantation management : a multi-scale investigation, Southeast Queensland, Australia." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/20657/1/Wang_Qing_Thesis.pdf.

Full text
Abstract:
Exotic pine plantations are a major landuse within the coastal lowlands of southeast Queensland, extending from close to the shoreline to the hinterland ranges. These plantations are within a sub-tropical climatic zone, and in most years, the summers are appreciably wetter than the winters. This terrain, in general, has been highly weathered and the soils are poor in nutrients. Environmental factors such as the climate, topography and weathering profile (including soil) are found to be important controls on vadose zone hydrology, which, in turn, has a great impact on tree growth and consequently on the design of management practices. This research project takes a holistic approach to investigate the influence of these environmental factors at different scales, and is designed to fulfil the following objectives: (1) To build a spatial model of forest productivity for the entire Tuan Toolara State Forest (TTSF), southeast Queensland, by analysing the spatial patterns of many environmental variables that may have controls on soil water distribution. (2) To determine how some of these environmental factors are responsible for the development of water-logging and soil salinisation by examining in detail an area of low site index that is severely affected by these two processes. (3) To develop a model to assess the risks of water-logging spatially and temporally. A multiple regression model was constructed to predict the forest productivity (measured by the value of site index, the average dominant tree height at 25 years of age). The independent variables were derived from a digital elevation model (elevation, slope, curvature, hillshade, flow accumulation and distance to streams), γ-ray spectrometry (potassium, thorium and uranium), and interpolated rainfall. The model explained up to 60% of the variance in the site indices and produced predictive maps of site index for two species: P. elliottii Engelm. and Queensland hybrid, a P. elliottii × P. caribaea Morelet hybrid. The model also identified the lowest site index area at the northern Tuan State Forest (NTSF), likely due to a greater risk of water-logging and salinisation. The NTSF area is of low relief and, therefore, the focus has been on the vertical controls of deep weathering profile. The methodology included setting up a network of groundwater bores screened at different depths within the weathering profile, characterising the profile (mineralogy, EC, and pH) and the groundwaters within it (water levels, physico-chemical parameters, major and minor ions). It is found that water-logging is caused by perched groundwater formed on top of the ferricrete or mottled saprolite after prolonged rainfall. Localised salinisation is related to the discharge of brackish groundwater occurring within the mottled saprolite. The deep aquifer within the coarse saprolite is fresh and not responsible for salinisation, a situation that differs from many other settings in Australia. The ability of using the Soil and Water Assessment Tool (SWAT) computer model to simulate soil water balance and to assess the risks of water-logging was tested in a selected catchment in the TTSF. The model successfully simulated stream flow at 2 weirs for a period of 6 years; the achieved R2 were 0.752 and 0.858, respectively. Long-term simulation for a 30-year period showed that there are pronounced seasonal patterns in rainfall and evapotranspiration as well as in soil water. For mature plantation with slopes of 3-15%, the mean annual duration of water-logging ranged from 161 days in the humus podzols, to 110 days in the gleyed podzolic, and to 90 days in the yellow podzolics. The outcomes of this research suggest that forest management can be strongly supported by understanding the impacts of these environmental factors (e.g. climate, topography and weathering profile) on vadose zone hydrological processes; the selection of optimum approach will depend on the research objective or purpose. The models and analytical tools that were developed or tested here have the potential to be successfully applied elsewhere if the input data are available.
APA, Harvard, Vancouver, ISO, and other styles
25

Wang, Qing. "Impacts of climate, topography, and weathering profile on vadose zone hydrology and coastal pine plantation management : a multi-scale investigation, Southeast Queensland, Australia." Queensland University of Technology, 2008. http://eprints.qut.edu.au/20657/.

Full text
Abstract:
Exotic pine plantations are a major landuse within the coastal lowlands of southeast Queensland, extending from close to the shoreline to the hinterland ranges. These plantations are within a sub-tropical climatic zone, and in most years, the summers are appreciably wetter than the winters. This terrain, in general, has been highly weathered and the soils are poor in nutrients. Environmental factors such as the climate, topography and weathering profile (including soil) are found to be important controls on vadose zone hydrology, which, in turn, has a great impact on tree growth and consequently on the design of management practices. This research project takes a holistic approach to investigate the influence of these environmental factors at different scales, and is designed to fulfil the following objectives: (1) To build a spatial model of forest productivity for the entire Tuan Toolara State Forest (TTSF), southeast Queensland, by analysing the spatial patterns of many environmental variables that may have controls on soil water distribution. (2) To determine how some of these environmental factors are responsible for the development of water-logging and soil salinisation by examining in detail an area of low site index that is severely affected by these two processes. (3) To develop a model to assess the risks of water-logging spatially and temporally. A multiple regression model was constructed to predict the forest productivity (measured by the value of site index, the average dominant tree height at 25 years of age). The independent variables were derived from a digital elevation model (elevation, slope, curvature, hillshade, flow accumulation and distance to streams), γ-ray spectrometry (potassium, thorium and uranium), and interpolated rainfall. The model explained up to 60% of the variance in the site indices and produced predictive maps of site index for two species: P. elliottii Engelm. and Queensland hybrid, a P. elliottii × P. caribaea Morelet hybrid. The model also identified the lowest site index area at the northern Tuan State Forest (NTSF), likely due to a greater risk of water-logging and salinisation. The NTSF area is of low relief and, therefore, the focus has been on the vertical controls of deep weathering profile. The methodology included setting up a network of groundwater bores screened at different depths within the weathering profile, characterising the profile (mineralogy, EC, and pH) and the groundwaters within it (water levels, physico-chemical parameters, major and minor ions). It is found that water-logging is caused by perched groundwater formed on top of the ferricrete or mottled saprolite after prolonged rainfall. Localised salinisation is related to the discharge of brackish groundwater occurring within the mottled saprolite. The deep aquifer within the coarse saprolite is fresh and not responsible for salinisation, a situation that differs from many other settings in Australia. The ability of using the Soil and Water Assessment Tool (SWAT) computer model to simulate soil water balance and to assess the risks of water-logging was tested in a selected catchment in the TTSF. The model successfully simulated stream flow at 2 weirs for a period of 6 years; the achieved R2 were 0.752 and 0.858, respectively. Long-term simulation for a 30-year period showed that there are pronounced seasonal patterns in rainfall and evapotranspiration as well as in soil water. For mature plantation with slopes of 3-15%, the mean annual duration of water-logging ranged from 161 days in the humus podzols, to 110 days in the gleyed podzolic, and to 90 days in the yellow podzolics. The outcomes of this research suggest that forest management can be strongly supported by understanding the impacts of these environmental factors (e.g. climate, topography and weathering profile) on vadose zone hydrological processes; the selection of optimum approach will depend on the research objective or purpose. The models and analytical tools that were developed or tested here have the potential to be successfully applied elsewhere if the input data are available.
APA, Harvard, Vancouver, ISO, and other styles
26

Seddelmeyer, Laura M. "All the Way with LBJ?: Australian Grand Strategy and the Vietnam War." Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1236630726.

Full text
Abstract:
Thesis (M.A.)--Ohio University, March, 2009.
Title from PDF t.p. Release of full electronic text on OhioLINK has been delayed until April 1, 2014. Includes bibliographical references (leaves 104-108)
APA, Harvard, Vancouver, ISO, and other styles
27

Lin, Chaofeng. "Iron biogeochemistry and associated greenhouse gas evolution in a forested subtropical Australian coastal catchment : Poona Creek, Southeast Queensland." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/47072/1/Chaofeng_Lin_Thesis.pdf.

Full text
Abstract:
Iron (Fe) is the fourth most abundant element in the Earth’s crust. Excess Fe mobilization from terrestrial into aquatic systems is of concern for deterioration of water quality via biofouling and nuisance algal blooms in coastal and marine systems. Substantial Fe dissolution and transport involve alternate Fe(II) oxidation followed by Fe(III) reduction, with a diversity of Bacteria and Archaea acting as the key catalyst. Microbially-mediated Fe cycling is of global significance with regard to cycles of carbon (C), sulfur (S) and manganese (Mn). However, knowledge regarding microbial Fe cycling in circumneutral-pH habitats that prevail on Earth has been lacking until recently. In particular, little is known regarding microbial function in Fe cycling and associated Fe mobilization and greenhouse (CO2 and CH4, GHG) evolution in subtropical Australian coastal systems where microbial response to ambient variations such as seasonal flooding and land use changes is of concern. Using the plantation-forested Poona Creek catchment on the Fraser Coast of Southeast Queensland (SEQ), this research aimed to 1) study Fe cycling-associated bacterial populations in diverse terrestrial and aquatic habitats of a representative subtropical coastal circumneutral-pH (4–7) ecosystem; and 2) assess potential impacts of Pinus plantation forestry practices on microbially-mediated Fe mobilization, organic C mineralization and associated GHG evolution in coastal SEQ. A combination of wet-chemical extraction, undisturbed core microcosm, laboratory bacterial cultivation, microscopy and 16S rRNA-based molecular phylogenetic techniques were employed. The study area consisted primarily of loamy sands, with low organic C and dissolved nutrients. Total reactive Fe was abundant and evenly distributed within soil 0–30 cm profiles. Organic complexation primarily controlled Fe bioavailability and forms in well-drained plantation soils and water-logged, native riparian soils, whereas tidal flushing exerted a strong “seawater effect” in estuarine locations and formed a large proportion of inorganic Fe(III) complexes. There was a lack of Fe(II) sources across the catchment terrestrial system. Mature, first-rotation plantation clear-felling and second-rotation replanting significantly decreased organic matter and poorly crystalline Fe in well-drained soils, although variations in labile soil organic C fractions (dissolved organic C, DOC; and microbial biomass C, MBC) were minor. Both well-drained plantation soils and water-logged, native-vegetation soils were inhabited by a variety of cultivable, chemotrophic bacterial populations capable of C, Fe, S and Mn metabolism via lithotrophic or heterotrophic, (micro)aerobic or anaerobic pathways. Neutrophilic Fe(III)-reducing bacteria (FeRB) were most abundant, followed by aerobic, heterotrophic bacteria (heterotrophic plate count, HPC). Despite an abundance of FeRB, cultivable Fe(II)-oxidizing bacteria (FeOB) were absent in associated soils. A lack of links between cultivable Fe, S or Mn bacterial densities and relevant chemical measurements (except for HPC correlated with DOC) was likely due to complex biogeochemical interactions. Neither did variations in cultivable bacterial densities correlate with plantation forestry practices, despite total cultivable bacterial densities being significantly lower in estuarine soils when compared with well-drained plantation soils and water-logged, riparian native-vegetation soils. Given that bacterial Fe(III) reduction is the primary mechanism of Fe oxide dissolution in soils upon saturation, associated Fe mobilization involved several abiotic and biological processes. Abiotic oxidation of dissolved Fe(II) by Mn appeared to control Fe transport and inhibit Fe dissolution from mature, first-rotation plantation soils post-saturation. Such an effect was not observed in clear-felled and replanted soils associated with low SOM and potentially low Mn reactivity. Associated GHG evolution post-saturation mainly involved variable CO2 emissions, with low, but consistently increasing CH4 effluxes in mature, first-rotation plantation soil only. In comparison, water-logged soils in the riparian native-vegetation buffer zone functioned as an important GHG source, with high potentials for Fe mobilization and GHG, particularly CH4 emissions in riparian loam soils associated with high clay and crystalline Fe fractions. Active Fe–C cycling was unlikely to occur in lower-catchment estuarine soils associated with low cultivable bacterial densities and GHG effluxes. As a key component of bacterial Fe cycling, neutrophilic FeOB widely occurred in diverse aquatic, but not terrestrial, habitats of the catchment study area. Stalked and sheathed FeOB resembling Gallionella and Leptothrix were limited to microbial mat material deposited in surface fresh waters associated with a circumneutral-pH seep, and clay-rich soil within riparian buffer zones. Unicellular, Sideroxydans-related FeOB (96% sequence identity) were ubiquitous in surface and subsurface freshwater environments, with highest abundance in estuary-adjacent shallow coastal groundwater water associated with redox transition. The abundance of dissolved C and Fe in the groundwater-dependent system was associated with high numbers of cultivable anaerobic, heterotrophic FeRB, microaerophilic, putatively lithotrophic FeOB and aerobic, heterotrophic bacteria. This research represents the first study of microbial Fe cycling in diverse circumneutral-pH environments (terrestrial–aquatic, freshwater–estuarine, surface–subsurface) of a subtropical coastal ecosystem. It also represents the first study of its kind in the southern hemisphere. This work highlights the significance of bacterial Fe(III) reduction in terrestrial, and bacterial Fe(II) oxidation in aquatic catchment Fe cycling. Results indicate the risk of promotion of Fe mobilization due to plantation clear-felling and replanting, and GHG emissions associated with seasonal water-logging. Additional significant outcomes were also achieved. The first direct evidence for multiple biomineralization patterns of neutrophilic, microaerophilic, unicellular FeOB was presented. A putatively pure culture, which represents the first cultivable neutrophilic FeOB from the southern hemisphere, was obtained as representative FeOB ubiquitous in diverse catchment aquatic habitats.
APA, Harvard, Vancouver, ISO, and other styles
28

PRINCE, Peter. "STRATEGIC PERCEPTIONS FROM INDONESIA, MALAYSIA AND SINGAPORE 1989-1992 AND THE IMPLICATIONS FOR AUSTRALIA'S SECURITY POLICIES." University of Sydney, Philosophy, 1993. http://hdl.handle.net/2123/391.

Full text
Abstract:
Indonesia, Malaysia and Singapore are of key strategic importance for Australia. These three nations form the geographic and arguably the political core of the Association of Southeast Asian Nations (ASEAN). The growing resilience of ASEAN over the last quarter of a century has been a major factor in Australia's secure strategic outlook. In addition, the Indonesia - Malaysia - Singapore triangle lies across the most feasible military approaches to Australia. Hence strategic cohesion in this triangle greatly reduces the prospect of any kind of military threat to Australia.
APA, Harvard, Vancouver, ISO, and other styles
29

Lamminmaki, Dawne, and n/a. "Outsourcing in the Hotel Industry: A Management Accounting Perpective." Griffith University. School of Accounting and Finance, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040920.091600.

Full text
Abstract:
The broad objective of this thesis is to develop an understanding of factors affecting outsourcing in the hotel industry and also the role played by management accounting in hotel outsourcing. The thesis draws on transaction cost economics (TCE), agency, contingency, and labour process theories in the context of appraising factors motivating outsourcing. Two empirical phases have been undertaken in the study. The first phase involved a series of interviews with general managers and financial controllers in large South East Queensland hotels. The second phase involved two distinct questionnaire surveys of large Australian hotels. The first was administered to hotel general managers, and the second was administered to hotel financial controllers. Significant findings arising from the study include: 1. In light of the substantial international literature describing hotel outsourcing, it appears that outsourcing in Australian hotels is relatively limited. This appears to be particularly the case with respect to food and beverage related activities. 2. Mixed support is offered for the TCE model. Both the survey and interview data provide some support for TCE's prescription that frequently conducted activities will not tend to be outsourced. Two specific extensions are offered to this aspect of the model, however. Firstly, where activities are conducted to a minimal extent, it can be uneconomic to outsource. Secondly, where large activities are undertaken by a group of organisations, their enhanced purchasing power can result in inexpensive outsourcing arrangements. With respect to TCE's uncertainty proposition, support is offered for the view that the propensity to outsource will be greater where behavioural uncertainty is lower. No support has been offered with respect to environmental uncertainty. The interview data provides some support for TCE's asset specificity proposition, however, minimal support was found in the survey phase. Despite this, the many dimensions of asset specificity (eg. site specificity, human asset specificity, etc) provided a useful checklist of issues to be considered in relation to the outsourcing decision. 3. Negligible support was found for labour process theory (LPT) in the interview phase of the study. In light of this, and the need to narrow the study’s focus in the survey phase, LPT was not pursued further. LPT is a difficult construct to operationalise, given the social desirability error that may result. This may partially account for the absence of significant LPT findings in the interview phase. 4. The survey data provides some support for the agency theory view that risky activities will tend to be outsourced. 5. Considerable cross-hotel variation exists in management of, and accounting's involvement in, outsourcing decision making and control systems. Accounting appraisal of outsourcing proposals rarely includes long term oriented, sophisticated techniques such as "net present value". It appears this may be because outsourcing decisions are not conducted in the context of the formal capital budgeting process. 6. High performing hotels and hotels that conduct their outsourcing decisions in the context of a long term outsourcing strategic agenda have more sophisticated outsourcing management systems.
APA, Harvard, Vancouver, ISO, and other styles
30

Labadz, Martin. "A catchment modelling approach integrating surface and groundwater processes, land use and distribution of nutrients : Elimbah Creek, southeast Queensland." Thesis, Queensland University of Technology, 2012. https://eprints.qut.edu.au/60017/1/Martin_Labadz_Thesis.pdf.

Full text
Abstract:
As the world’s population is growing, so is the demand for agricultural products. However, natural nitrogen (N) fixation and phosphorus (P) availability cannot sustain the rising agricultural production, thus, the application of N and P fertilisers as additional nutrient sources is common. It is those anthropogenic activities that can contribute high amounts of organic and inorganic nutrients to both surface and groundwaters resulting in degradation of water quality and a possible reduction of aquatic life. In addition, runoff and sewage from urban and residential areas can contain high amounts of inorganic and organic nutrients which may also affect water quality. For example, blooms of the cyanobacterium Lyngbya majuscula along the coastline of southeast Queensland are an indicator of at least short term decreases of water quality. Although Australian catchments, including those with intensive forms of land use, show in general a low export of nutrients compared to North American and European catchments, certain land use practices may still have a detrimental effect on the coastal environment. Numerous studies are reported on nutrient cycling and associated processes on a catchment scale in the Northern Hemisphere. Comparable studies in Australia, in particular in subtropical regions are, however, limited and there is a paucity in the data, in particular for inorganic and organic forms of nitrogen and phosphorus; these nutrients are important limiting factors in surface waters to promote algal blooms. Therefore, the monitoring of N and P and understanding the sources and pathways of these nutrients within a catchment is important in coastal zone management. Although Australia is the driest continent, in subtropical regions such as southeast Queensland, rainfall patterns have a significant effect on runoff and thus the nutrient cycle at a catchment scale. Increasingly, these rainfall patterns are becoming variable. The monitoring of these climatic conditions and the hydrological response of agricultural catchments is therefore also important to reduce the anthropogenic effects on surface and groundwater quality. This study consists of an integrated hydrological–hydrochemical approach that assesses N and P in an environment with multiple land uses. The main aim is to determine the nutrient cycle within a representative coastal catchment in southeast Queensland, the Elimbah Creek catchment. In particular, the investigation confirms the influence associated with forestry and agriculture on N and P forms, sources, distribution and fate in the surface and groundwaters of this subtropical setting. In addition, the study determines whether N and P are subject to transport into the adjacent estuary and thus into the marine environment; also considered is the effect of local topography, soils and geology on N and P sources and distribution. The thesis is structured on four components individually reported. The first paper determines the controls of catchment settings and processes on stream water, riverbank sediment, and shallow groundwater N and P concentrations, in particular during the extended dry conditions that were encountered during the study. Temporal and spatial factors such as seasonal changes, soil character, land use and catchment morphology are considered as well as their effect on controls over distributions of N and P in surface waters and associated groundwater. A total number of 30 surface and 13 shallow groundwater sampling sites were established throughout the catchment to represent dominant soil types and the land use upstream of each sampling location. Sampling comprises five rounds and was conducted over one year between October 2008 and November 2009. Surface water and groundwater samples were analysed for all major dissolved inorganic forms of N and for total N. Phosphorus was determined in the form of dissolved reactive P (predominantly orthophosphate) and total P. In addition, extracts of stream bank sediments and soil grab samples were analysed for these N and P species. Findings show that major storm events, in particular after long periods of drought conditions, are the driving force of N cycling. This is expressed by higher inorganic N concentrations in the agricultural subcatchment compared to the forested subcatchment. Nitrate N is the dominant inorganic form of N in both the surface and groundwaters and values are significantly higher in the groundwaters. Concentrations in the surface water range from 0.03 to 0.34 mg N L..1; organic N concentrations are considerably higher (average range: 0.33 to 0.85 mg N L..1), in particular in the forested subcatchment. Average NO3-N in the groundwater has a range of 0.39 to 2.08 mg N L..1, and organic N averages between 0.07 and 0.3 mg N L..1. The stream bank sediments are dominated by organic N (range: 0.53 to 0.65 mg N L..1), and the dominant inorganic form of N is NH4-N with values ranging between 0.38 and 0.41 mg N L..1. Topography and soils, however, were not to have a significant effect on N and P concentrations in waters. Detectable phosphorus in the surface and groundwaters of the catchment is limited to several locations typically in the proximity of areas with intensive animal use; in soil and sediments, P is negligible. In the second paper, the stable isotopes of N (14N/15N) and H2O (16O/18O and 2H/H) in surface and groundwaters are used to identify sources of dissolved inorganic and organic N in these waters, and to determine their pathways within the catchment; specific emphasis is placed on the relation of forestry and agriculture. Forestry is predominantly concentrated in the northern subcatchment (Beerburrum Creek) while agriculture is mainly found in the southern subcatchment (Six Mile Creek). Results show that agriculture (horticulture, crops, grazing) is the main source of inorganic N in the surface waters of the agricultural subcatchment, and their isotopic signature shows a close link to evaporation processes that may occur during water storage in farm dams that are used for irrigation. Groundwaters are subject to denitrification processes that may result in reduced dissolved inorganic N concentrations. Soil organic matter delivers most of the inorganic N to the surface water in the forested subcatchment. Here, precipitation and subsequently runoff is the main source of the surface waters. Groundwater in this area is affected by agricultural processes. The findings also show that the catchment can attenuate the effects of anthropogenic land use on surface water quality. Riparian strips of natural remnant vegetation, commonly 50 to 100 m in width, act as buffer zones along the drainage lines in the catchment and remove inorganic N from the soil water before it enters the creek. These riparian buffer zones are common in most agricultural catchments of southeast Queensland and are indicated to reduce the impact of agriculture on stream water quality and subsequently on the estuary and marine environments. This reduction is expressed by a significant decrease in DIN concentrations from 1.6 mg N L..1 to 0.09 mg N L..1, and a decrease in the �15N signatures from upstream surface water locations downstream to the outlet of the agricultural subcatchment. Further testing is, however, necessary to confirm these processes. Most importantly, the amount of N that is transported to the adjacent estuary is shown to be negligible. The third and fourth components of the thesis use a hydrological catchment model approach to determine the water balance of the Elimbah Creek catchment. The model is then used to simulate the effects of land use on the water balance and nutrient loads of the study area. The tool that is used is the internationally widely applied Soil and Water Assessment Tool (SWAT). Knowledge about the water cycle of a catchment is imperative in nutrient studies as processes such as rainfall, surface runoff, soil infiltration and routing of water through the drainage system are the driving forces of the catchment nutrient cycle. Long-term information about discharge volumes of the creeks and rivers do, however, not exist for a number of agricultural catchments in southeast Queensland, and such information is necessary to calibrate and validate numerical models. Therefore, a two-step modelling approach was used to calibrate and validate parameters values from a near-by gauged reference catchment as starting values for the ungauged Elimbah Creek catchment. Transposing monthly calibrated and validated parameter values from the reference catchment to the ungauged catchment significantly improved model performance showing that the hydrological model of the catchment of interest is a strong predictor of the water water balance. The model efficiency coefficient EF shows that 94% of the simulated discharge matches the observed flow whereas only 54% of the observed streamflow was simulated by the SWAT model prior to using the validated values from the reference catchment. In addition, the hydrological model confirmed that total surface runoff contributes the majority of flow to the surface water in the catchment (65%). Only a small proportion of the water in the creek is contributed by total base-flow (35%). This finding supports the results of the stable isotopes 16O/18O and 2H/H, which show the main source of water in the creeks is either from local precipitation or irrigation waters delivered by surface runoff; a contribution from the groundwater (baseflow) to the creeks could not be identified using 16O/18O and 2H/H. In addition, the SWAT model calculated that around 68% of the rainfall occurring in the catchment is lost through evapotranspiration reflecting the prevailing long-term drought conditions that were observed prior and during the study. Stream discharge from the forested subcatchment was an order of magnitude lower than discharge from the agricultural Six Mile Creek subcatchment. A change in land use from forestry to agriculture did not significantly change the catchment water balance, however, nutrient loads increased considerably. Conversely, a simulated change from agriculture to forestry resulted in a significant decrease of nitrogen loads. The findings of the thesis and the approach used are shown to be of value to catchment water quality monitoring on a wider scale, in particular the implications of mixed land use on nutrient forms, distributions and concentrations. The study confirms that in the tropics and subtropics the water balance is affected by extended dry periods and seasonal rainfall with intensive storm events. In particular, the comprehensive data set of inorganic and organic N and P forms in the surface and groundwaters of this subtropical setting acquired during the one year sampling program may be used in similar catchment hydrological studies where these detailed information is missing. Also, the study concludes that riparian buffer zones along the catchment drainage system attenuate the transport of nitrogen from agricultural sources in the surface water. Concentrations of N decreased from upstream to downstream locations and were negligible at the outlet of the catchment.
APA, Harvard, Vancouver, ISO, and other styles
31

Thompson, Chris J. Physical Environmental &amp Mathematical Sciences Australian Defence Force Academy UNSW. "The geomorphology of Southeast Australian mountain streams." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Physical, Environmental and Mathematical Sciences, 2006. http://handle.unsw.edu.au/1959.4/38681.

Full text
Abstract:
This thesis is a study of the morphology and sediment transport dynamics of mountain streams in southeast Australia. Mountain streams represent important geomorphological and ecological systems in Australia which have hitherto been poorly studied. The variability of mountain stream reach morphology was investigated at the regional scale using topographical surveys and sediment sampling techniques. Study sites were stratified by slope and local lithology. Eight channel-morphologies including Bedrock, Cascade, Step-pool, Planebed, Pool-Riffle, Cascade-pool, Riffle-step and Infilled, were identified using an objective statistical approach. Overall, channel types were found to correspond to existing reach-scale mountain stream templates. Five morphologies were associated with a specific lithology type which controlled the size and shape of grains supplied to the channels. Differences in coarse sediment transport processes between morphologies were investigated using stream monitoring techniques and Optically Stimulated Luminescence (OSL) dating. Monitoring results from a 3 year period indicated that channel beds are resistant to entrainment with shear stress thresholds for bedload transport ranging between 64 to 74 N/m2. Transport of reach median grain sizes requires floods that exceed bankfull discharge. Existing competence equations were found to over-predict the hydraulic driving force and consequently, a modified entrainment model was used to account for the regional channel characteristics. OSL dating was investigated as a tool to provide data on long-term sediment transport processes. Minimum age model results from the OSL dates show overall agreement with a selected entrainment model, and indicate differences in sediment transport dynamics between some reach morphology types. A regime model was used to quantify the physical domains of different channel morphologies. Limitations of the model were overcome by modifying the sediment supply surrogate to better reflect the dominant transported bedload size. Morphology types were delineated according to different sediment transport capacity-sediment supply domains. The distribution of channel morphology types within a series of catchments in southeast Australia was modelled within a GIS platform using the diagnostics of reach morphology derived from this study. The model provides a conceptual framework to evaluate the potential link between channel form, potential habitat diversity and aquatic biodiversity within the channel network in mountain streams.
APA, Harvard, Vancouver, ISO, and other styles
32

de, Somer Gregory John Humanities &amp Social Sciences Australian Defence Force Academy UNSW. "The Redefinition of Asia : Australian Foreign Policy and Contemporary Asian Regionalism." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Humanities and Social Sciences, 2003. http://handle.unsw.edu.au/1959.4/38666.

Full text
Abstract:
This thesis set out to ascertain the position of recent Australian Governments on the latest instalments of Asian regionalism in the context of an assessment of whether there has been a redefinition of Asia and thus a redefinition of Australia???s engagement with Asia. It will concentrate on the broad themes of politico-strategic and economic engagement. Whilst there has been extensive research and documentation on the Asian economic crisis there has been less work on the issue of a new Asian regionalism and the implications for Australia???s complex and variable engagement with the region. This is the basis for the claim to originality of this thesis, a claim supported by its focus on the practical and policy implications of Australia???s engagement, or lack of it, with regional institutions. The process of regional integration has been extremely slow, thus supporting the conclusion that there is no evidence of a major redefinition of Asia. Efforts at Asian regionalism are meeting obstacles that pose immense challenges. Asian regionalism remains nascent and poorly defined. This reflects the diversity and enormous disparities in cultures, political systems and the levels of economic development and differences over economic philosophies within East Asia. What is discernible is that the regionalism is proceeding more rapidly on financial issues than on trade, and in the security area it is conspicuously absent. This research highlights the fact that the question of Asian engagement remains a sensitive issue in Australia and continues to grow more complex. Australia???s engagement with Asia since 1996 has been variable because of the Howard Government???s broader balance of priorities between global and regional issues, and because of the changing nature of the Asian region. The perception gleaned from sources is that, for the Australian Government, regionalism initiatives are characterised by much discussion but lack substance. Consequently, this appears to have led the Government to the position that exclusion from some manifestations of regionalism is not so important. Australia is excluded from some of the regional architectures being constructed. In its efforts to seek inclusion in ASEAN + 3 and ASEM, Australia is facing the same barriers that have stood in the way of an AFTA-CER agreement. Exclusion would be important if the performance of regional groupings was not so indifferent. Exclusion from ASEAN + 3 and ASEM, however, does not equate to Australia???s exclusion from the region.
APA, Harvard, Vancouver, ISO, and other styles
33

Doering, Che. "Measurements of the distribution and behaviour of Beryllium-7 in the natural environment." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16513/1/Che_Doering_Thesis.pdf.

Full text
Abstract:
Beryllium-7 is a cosmogenic radionuclide produced in the atmosphere through the spallation of nitrogen and oxygen nuclei by cosmic-ray-produced neutrons and protons. It is carried in the atmosphere attached to aerosols and is deposited on land and ocean surfaces by wet and dry deposition processes. Beryllium-7 decays by electron capture to lithium-7 and has a half-life of approximately 53 days. It is a potentially useful radionuclide for studying different natural processes. This thesis presents a collection of scientific papers on the occurrence of beryllium-7 in the natural environment, particularly in the Southeast Queensland region of Australia. It shows the results of experimental measurements and discusses their implications. Overall, this thesis contributes to advancing our understanding of the distribution and behaviour of beryllium-7 in the natural environment and provides a foundation for the development of nuclear techniques for the evaluation of environmental problems.
APA, Harvard, Vancouver, ISO, and other styles
34

Doering, Che. "Measurements of the distribution and behaviour of Beryllium-7 in the natural environment." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16513/.

Full text
Abstract:
Beryllium-7 is a cosmogenic radionuclide produced in the atmosphere through the spallation of nitrogen and oxygen nuclei by cosmic-ray-produced neutrons and protons. It is carried in the atmosphere attached to aerosols and is deposited on land and ocean surfaces by wet and dry deposition processes. Beryllium-7 decays by electron capture to lithium-7 and has a half-life of approximately 53 days. It is a potentially useful radionuclide for studying different natural processes. This thesis presents a collection of scientific papers on the occurrence of beryllium-7 in the natural environment, particularly in the Southeast Queensland region of Australia. It shows the results of experimental measurements and discusses their implications. Overall, this thesis contributes to advancing our understanding of the distribution and behaviour of beryllium-7 in the natural environment and provides a foundation for the development of nuclear techniques for the evaluation of environmental problems.
APA, Harvard, Vancouver, ISO, and other styles
35

Davidson, Michael Cameron Gordon, and M. Davidson@mailbox gu edu au. "Organisational climate and its influence upon performance: A study of Australian hotels in South East Queensland." Griffith University. School of Marketing and Management, 2000. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030102.103647.

Full text
Abstract:
This study gathered data from 14 four to five-star hotels in South-East Queensland, Australia, in an attempt to examine the nature and degree of influence organisational climate has upon the performance of hotels. Employee perception of customer satisfaction was studied both as an index of performance and as an intervening variable between organisational climate and financial performance as indexed by revenue per available room (REVPAR). The data provided a description of a young, relatively gender balanced, well educated and trained work force which received relatively low levels of financial remuneration and displayed very high levels of turnover. A new instrument was used to measure the dimensions of organisational climate across the hotels. This instrument represented a modification of that presented by Ryder and Southey (1990), which itself was a modification of the 145 item psychological climate questionnaire of Jones and James (1979). The instrument represented a subset of 70 items of the Ryder and Southey instrument. Responses to all items within the instrument were on a 7 point anchored scale. Principal components analysis (PCA) produced results consistent with earlier versions of the instrument, which had been reported elsewhere. This analysis described organisational climate within the sample to be composed of 7 underlying dimensions; Leader facilitation and support, Professional and organisational esprit, Conflict and ambiguity, Regulations, organisation and pressure, Job variety, challenge and autonomy, Workgroup co-operation, friendliness and warmth, and Job standards. These dimensions were judged to be consistent with those reported earlier by Jones and James, and by Ryder and Southey. Poor support was found for the first structural model that proposed that employee demographic variables would affect organisational climate and that organisational climate would affect customer satisfaction (although the latter link was quite strong). The most important finding of the study was the support for a second structural model when it was found that variation in the 7 dimensions of organisational climate accounted for 30% of the variation in Employee Perception of Customer Satisfaction. Furthermore, that Employee Perception of Customer Satisfaction accounted for 23% of the variation in REVPAR between the hotels. Possible extensions of this study using direct measures of customer satisfaction and expanding it to include hotels of different star ratings are discussed.
APA, Harvard, Vancouver, ISO, and other styles
36

Lamb, Jenna. "The raw and the cooked : a study on the effects of cooking on three aboriginal plant foods from Southeast Queensland /." St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17592.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
37

Haddam, Naoufel Abdeldjalyl. "Rôle de l’Océan Austral dans les variations climatiques rapides de la dernière transition Glaciaire-Holocène : approche géochimique et micropaléontologique." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS555/document.

Full text
Abstract:
Les derniers 22 kans sont marqués par des évènements climatiques rapides, non synchrones entre l‘hémisphère Sud et le Nord. Un mécanisme de bascule des températures polaires, amplifié par la capacité de l‘océan profond à stocker et à restituer une partie du CO₂ atmosphérique en fonction de l‘intensité de la circulation océanique et des upwellings le long de la divergence Australe, a été proposé pour expliquer ces évènements. L‘objectif principal de cette thèse a été de définir quel est le rôle de l‘Océan Austral durant ces variations climatiques rapides à l‘aide de 3 carottes sédimentaires marines, prélevées le long de la marge chilienne, sous l‘influence des fronts océaniques et des vents d‘Ouest. La reconstitution des températures océaniques de surface (SST) ont permis de retracer l‘évolution du gradient latitudinal de SST au cours des derniers 22 kans mettant en évidence des migrations vers le sud du front Subtropical, notamment durant la déglaciation,marqués par des changements faunistiques en foraminifères planctoniques et benthiques suggérant unapport accru de nutriments en surface, et accompagnés par un enrichissement en [O₂] dans l‘eau de fond. Ces évènements sont peut-être liés à un renforcement des upwellings au niveau de la divergence australe induisant un renforcement de la ventilation des eaux intermédiaires antarctiques. Ces variations hydrologiques se produisent durant la hausse de CO₂ atmosphérique enregistrée dans les carottes de glace antarctiques pendant la déglaciation, indiquant un lien intime entre les upwellings, l‘intensité de la ventilation des eaux intermédiaires et le transfert de CO₂ depuis l‘océan profond vers l‘atmosphère
The last 22 kyr are marked by abrupt climatic events, non-synchronous between the southern and northern hemispheres. A see-saw mechanism of the polar temperatures, amplified by the deep oceanability to store and release a portion of atmospheric CO₂, depending on the intensity of the thermohaline circulation and the large upwellings along the southern divergence, has been proposed to explain these observations. The main aim of this thesis was to assess the role of the southern ocean during these millennial events, by studying 3 marine cores, retrieved along the Chilean margin, under the influence of oceanic fronts and the westerly winds. The reconstruction of the sea surface temperatures (SST) allowed tracing the evolution of the SST latitudinal gradient during the last 22 kyr, highlighting southward migrations of the Subtropical Front, especially during the deglaciation, marked by benthic and planktonic foraminifera faunal changes which can be interpreted as surface nutrients inputs increase, accompanied by an enrichment of the bottom water [O₂] in the bottom water. These events could be related to stronger upwellings at the southern divergence leading to an increase of the Antarctic intermediate waters ventilation. These changes occur during atmospheric CO₂ increases recorded in Antarctic ice cores, marking the deglaciation, and suggesting an intimate link between upwellings, the intensity of the intermediate waters ventilation, and deep ocean-atmosphere CO₂ transfers
APA, Harvard, Vancouver, ISO, and other styles
38

Brookhouse, Matthew Theodore. "A dendroclimatological reconnaissance of eucalypts in southeast Australia." Phd thesis, 2007. http://hdl.handle.net/1885/151433.

Full text
APA, Harvard, Vancouver, ISO, and other styles
39

Land, Clare. "The politics of solidarity with indigenous struggles in Southeast Australia." Thesis, 2012. https://vuir.vu.edu.au/31441/.

Full text
APA, Harvard, Vancouver, ISO, and other styles
40

Edmonds, Frances. "‘Art is us’: Aboriginal art, identity and wellbeing in Southeast Australia." 2007. http://repository.unimelb.edu.au/10187/7112.

Full text
Abstract:
Aboriginal arts practices in the southeast of Australia have, since the early years of colonisation, been rarely considered within the realm of authentic Aboriginal arts practices. Such attitudes were a reflection of the colonial encounter and associated attempts to assimilate the Aboriginal population with the White. This thesis explores Aboriginal arts practices and asserts that there has always been Aboriginal art in the southeast and that, despite the overwhelming effects of colonisation, the work of Aboriginal artists provides a distinct and definite counter-history to that endorsed by the dominant culture. Using published historical and contemporary accounts and recent interviews from Aboriginal artists and arts workers, this thesis investigates the continuation of the knowledge and practice of southeast Australian Aboriginal art and its connection to culture, identity and wellbeing. It explores the corresponding adaptations and changes to these practices as Aboriginal people contended with the ever-expanding European occupation of the region from 1834 onwards.
This project adopted a collaborative research methodology, where members of the Aboriginal arts community were consulted throughout the project in order to develop a study which had meaning and value for them. The collaborative approach combined an analysis of historical data along with the stories collected from participants. By privileging the Aboriginal voice as legitimate primary source material, alternative ways of exploring the history of Aboriginal art were possible. Although the story of Aboriginal art in the southeast is also one of tensions and paradoxes, where changes in arts practices frequently positioned art, like the people themselves, outside the domain of the ‘real’, the findings of this project emphasise that arts practices assist people with connecting and in some cases reconnecting with their communities. Aboriginal art in the southeast is an assertion of identity and wellbeing and reflects the dynamic nature of Aboriginal culture in southeast Australia.
APA, Harvard, Vancouver, ISO, and other styles
41

Henwood, Murray James. "Biosystematic aspects of Polyscias J.R.& G.Forst. in Malesia and Australia." Phd thesis, 1988. http://hdl.handle.net/1885/142180.

Full text
APA, Harvard, Vancouver, ISO, and other styles
42

Berananda, Usana. "Australia's involvement in the Cambodian peace settlement : the Red Book initiative." Thesis, 1995. http://hdl.handle.net/1885/145650.

Full text
APA, Harvard, Vancouver, ISO, and other styles
43

Nelson, Emma Jane. "Present-day stress in Central and Southeast Australian sedimentary basins." 2007. http://hdl.handle.net/2440/45071.

Full text
Abstract:
This thesis consists of six published papers. The present-day stress tensor has been determined using petroleum well data in the Gippsland and Otway Basins in Southeast Australia (Papers 1 and 4) and the Cooper Basin in Central Australia (Paper 5). In the Gippsland Basin, the present-day stress regime is transitional between one of reverse and strike-slip faulting and the maximum horizontal stress (SHmax) is oriented ~139°N. The present-day stress regime in the Victorian sector of the Otway Basin is also transitional between one of reverse and strike-slip faulting and SHmax is oriented ~135°N. Horizontal stresses are lower in the South Australian sector of the Otway Basin where the stress regime is one of strike-slip faulting and SHmax is oriented ~124°N. The orientations of SHmax in Southeast Australia are consistent with focal mechanism solutions, neotectonic structures and modelling of plate-boundary forces (Paper 4). Closure pressures from mini-frac injection tests are commonly used to determine the minimum horizontal stress (Shmin) magnitude. However, in high stress basins such as the Cooper and Gippsland Basins, these pressures may not reliably yield Shmin (Papers 2 and 5). In the Cooper Basin, high closure pressures (>18 MPa/km) were observed in tests where pressure-declines indicated complex hydraulic fracture growth. Closure pressures in these injections are unlikely to be representative of Shmin. They are believed to reflect the normal stress incident on pre-existing planes of weakness that are exploited by hydraulic fluid during the mini-frac injection (Paper 5). Sub-horizontal fabrics that are open at the wellbore wall were observed on image logs in the Cooper and Gippsland Basins (Papers 2 and 5). This fabric is believed to be at least partially responsible for the complex growth of hydraulic fractures observed in the Cooper Basin. The occurrence of these sub-horizontal fabrics and knowledge of rock strength have been used to constrain the magnitudes of SHmax and Shmin independently of mini-frac injections in the Cooper and Gippsland Basins (Papers 2 and 5). The present-day stress tensor is often quoted as a single gradient at a sedimentary basinor petroleum field-scale. Image logs and mini-frac data from Central and Southeast Australia indicate significant stress differences between stratigraphic units (Papers 3 and 5). Finite element modelling of the stress distribution between interbedded sands and shales in the Gippsland Basin indicates that stress is ‘partitioned’ to ‘hard’ lithological units in high stress areas. This accounts for the observation that borehole breakout only occurs in hard, cemented sandstones in the Gippsland Basin (Paper 3). A generic ‘mechanical stratigraphy’ derived from knowledge of wellbore failure (from image logs), rock strength and rock properties in individual rock units in the Cooper Basin allows an approximation of the present-day stress-state to be made directly from image-logs for individual rock units prior to mini-frac injection (Paper 6). This is important for predicting and understanding hydraulic fracture growth and containment. When considered together, the papers comprising this thesis provide significant new data on the orientation and magnitude of present-day stresses in Central and Southeast Australia. They also provide insight into the tectonic origin of those stresses and their distribution within sedimentary basins. In particular the papers develop and use new methods for constraining the present-day stress in regions of high tectonic stress. They also discuss implications for problems in petroleum development including wellbore stability and hydraulic fracturing.
http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1283781
Thesis(Ph.D.) -- Australian School of Petroleum, 2007
APA, Harvard, Vancouver, ISO, and other styles
44

Nelson, Emma Jane. "Present-day stress in Central and Southeast Australian sedimentary basins." Thesis, 2007. http://hdl.handle.net/2440/45071.

Full text
Abstract:
This thesis consists of six published papers. The present-day stress tensor has been determined using petroleum well data in the Gippsland and Otway Basins in Southeast Australia (Papers 1 and 4) and the Cooper Basin in Central Australia (Paper 5). In the Gippsland Basin, the present-day stress regime is transitional between one of reverse and strike-slip faulting and the maximum horizontal stress (SHmax) is oriented ~139°N. The present-day stress regime in the Victorian sector of the Otway Basin is also transitional between one of reverse and strike-slip faulting and SHmax is oriented ~135°N. Horizontal stresses are lower in the South Australian sector of the Otway Basin where the stress regime is one of strike-slip faulting and SHmax is oriented ~124°N. The orientations of SHmax in Southeast Australia are consistent with focal mechanism solutions, neotectonic structures and modelling of plate-boundary forces (Paper 4). Closure pressures from mini-frac injection tests are commonly used to determine the minimum horizontal stress (Shmin) magnitude. However, in high stress basins such as the Cooper and Gippsland Basins, these pressures may not reliably yield Shmin (Papers 2 and 5). In the Cooper Basin, high closure pressures (>18 MPa/km) were observed in tests where pressure-declines indicated complex hydraulic fracture growth. Closure pressures in these injections are unlikely to be representative of Shmin. They are believed to reflect the normal stress incident on pre-existing planes of weakness that are exploited by hydraulic fluid during the mini-frac injection (Paper 5). Sub-horizontal fabrics that are open at the wellbore wall were observed on image logs in the Cooper and Gippsland Basins (Papers 2 and 5). This fabric is believed to be at least partially responsible for the complex growth of hydraulic fractures observed in the Cooper Basin. The occurrence of these sub-horizontal fabrics and knowledge of rock strength have been used to constrain the magnitudes of SHmax and Shmin independently of mini-frac injections in the Cooper and Gippsland Basins (Papers 2 and 5). The present-day stress tensor is often quoted as a single gradient at a sedimentary basinor petroleum field-scale. Image logs and mini-frac data from Central and Southeast Australia indicate significant stress differences between stratigraphic units (Papers 3 and 5). Finite element modelling of the stress distribution between interbedded sands and shales in the Gippsland Basin indicates that stress is ‘partitioned’ to ‘hard’ lithological units in high stress areas. This accounts for the observation that borehole breakout only occurs in hard, cemented sandstones in the Gippsland Basin (Paper 3). A generic ‘mechanical stratigraphy’ derived from knowledge of wellbore failure (from image logs), rock strength and rock properties in individual rock units in the Cooper Basin allows an approximation of the present-day stress-state to be made directly from image-logs for individual rock units prior to mini-frac injection (Paper 6). This is important for predicting and understanding hydraulic fracture growth and containment. When considered together, the papers comprising this thesis provide significant new data on the orientation and magnitude of present-day stresses in Central and Southeast Australia. They also provide insight into the tectonic origin of those stresses and their distribution within sedimentary basins. In particular the papers develop and use new methods for constraining the present-day stress in regions of high tectonic stress. They also discuss implications for problems in petroleum development including wellbore stability and hydraulic fracturing.
Thesis(Ph.D.) -- Australian School of Petroleum, 2007
APA, Harvard, Vancouver, ISO, and other styles
45

Capili, Jose Wendell P. "Migrations and mediations : the emergence of Southeast Asian diaspora writers in Australia, 1972-2006." Phd thesis, 2007. http://hdl.handle.net/1885/150957.

Full text
APA, Harvard, Vancouver, ISO, and other styles
46

Okamoto, Jiro. "Australia's foreign economic policy and ASEAN." Phd thesis, 2006. http://hdl.handle.net/1885/149958.

Full text
APA, Harvard, Vancouver, ISO, and other styles
47

Broadbent, Stephen J. "Australia's defence export policy." Master's thesis, 1996. http://hdl.handle.net/1885/145187.

Full text
APA, Harvard, Vancouver, ISO, and other styles
48

Ogden, Ralph Winston. "The impacts of farming and river regulation on billsbongs of the Southeast Murray Basin, Australia." Phd thesis, 1996. http://hdl.handle.net/1885/110241.

Full text
Abstract:
This thesis is an investigation into the effects of farming and river regulation on billabong (floodplain lake) ecology. The study region is in the southeast comer of the Murray-Darling Basin. Billabongs comprise a significant natural freshwater lake system in the one million km2 drainage basin dominated by semi-arid conditions. The region was settled by Europeans in the middle 1800's, and early farming, activities, mainly the running of cattle and sheep, were particularly intense. Extensive timber extraction also occurred at this time. Both these activities have probably declined to a degree since the early 1900's but are practised in the region today. Fertiliser use became widespread in the 1930's. River regulation did not begin in earnest until the construction of the Hume Dam in 1930. In the study region regulation has decreased monthly variation in river flows, mainly by maintaining unnaturally high flows during summer irrigation demand, increased daily flow variability with short-term releases, decreased the frequency of minor flooding, slightly increased flood duration, and decreased sediment loads near weirs. These and other impacts of European settlement on the regional landscape are profound, and may have an effect on billabong limnology. Concepts of disturbance ecology are used as a framework for assessing changes to the biota living in billabongs resulting from European settlement. Two complementary lines of evidence are followed, one physicochemical and one biological, and evidence for the impacts of farming and regulation is sought from both historic and present day patterns of limnology. The limnology of 43 billabongs influenced to varying degrees by farming and regulation were surveyed every 2 months over a 15 month period. The billabongs vary in mean depth from about 0.3 to 4.5 m, and significant fluctuations in depth occur, both seasonally and between wet and drought periods. Natural variation in total nitrogen, total phosphorus, turbidity, and secchi depth billabongs is marked and dominated by temporal factors; mainly fluctuations in depth accompanying seasons and droughts, but also flooding. Significant shorter-term temporal variation is also implied from the data. In contrast, natural variation in pH is minor and salinity is always low. Maximum depth is the only systematic source of natural spatial variation revealed, apart from a slight east-west shift in major ion balance; the main determinants of nutrient limnology and light environment of billabongs found in this study are temporal factors. Since natural variation in physicochemistry is dominated by relatively cyclical factors (seasons and floods), much natural disturbance in billabongs appears to be of the pulse variety, and to be moderately to highly predictable. It is likely the biota have evolved adaptations for this variation. Farming only affects phosphorus and salinity, but the effect on phosphorus is minor in comparison to natural variation, and salinity levels remain low. In contrast, river regulation has important direct effects on billabong depth, which on the decadal scale translates to billabong permanence. The indirect effects of regulation on nutrients and the light environment, from effects on depth, are likely to equal natural variation. However, most of the anthropogenic variation mimics natural variation, and the biota may already possess the adaptations to deal with it (may be 'preadapted'). The pattern of rapid depth fluctuations and summer flooding of low-lying billabongs created by regulation is 'new' to the ecosystem, at least in the current climatic regime, and the biota may not cope as well with this. Based on the skeletal remains of Cladocera in the surface sediments of 41 billabongs, farming and river regulation cause a relatively minor impact on the cladoceran fauna. Farming and regulation both affect some uncommon species, and regulation affects the overall diversity, richness and equitability of assemblages. Farming therefore has less of an effect than regulation, which is consistent with the patterns of physicochemistry observed. However, on the whole, assemblages from farmed and regulated billabongs are not very different from those in billabongs remote from farms and on unregulated river reaches, suggesting that the Cladocera are 'preadapted' to anthropogenic environmental variation by relatively high natural variation in physicochemistry. The above conclusions of no or low impact of farming and regulation on billabongs rely on billabongs remote from farms and on unregulated river reaches being unimpacted by these land use activities. This assumption is tested by examining the historical sedimentary record of billabongs. The historical record of physicochemistry in 8 billabongs was examined. Sedimentation rates are currently about 5 mm per year, but have increased by an order of magnitude since settlement. Based on the stratigraphy of sediment structure, organic matter content, and the atomic ratio Fe:Mn, redox conditions have changed in a minimum of 4 billabongs and a maximum of 6 since settlement. These include billabongs on unregulated river reaches and presently distant from farms. The direction of change is usually towards more oxidising conditions, but it is possible that the interpretation of the direction of changing redox (as distinct from the occurrence of changing redox) has been corrupted by the higher sedimentation rates following settlement. External phosphorus loading has, if anything, declined since settlement, but it is more likely that no change has occurred at all and that the patterns of phosphorus are due to the changing redox conditions. Because redox conditions have changed in billabongs considered as low-impact controls, assessments of impact based on the present day limnology of billabongs may underestimate the effects of farming and river regulation. The historical record of both Cladocera and the extent of macrophyte cover are inferred from the stratigraphy of cladoceran assemblages in the sediments, and the record of siliceous algal productivity is obtained from profiles of loosely bound silica. Aquatic macrophyte abundance in 5 of 7 billabongs examined decreases markedly at settlement, notwithstanding that taphonomic alteration of assemblages increases. The pattern is most pronounced in large, deep billabongs, and absent from small billabongs. The decline in macrophytes appears to have resulted in the demise of a group of closely related Rak or Ephemeroporus species that are codominant before settlement. Otherwise, the regional diversity of Cladocera has changed little with settlement, and possibly even increased from the introduction of exotic species. However, temporal trends in 7 species suggest they will be pushed towards regional extinction in the future. Siliceous algal productivity appears to have decreased in 4 of 7 billabongs with settlement, although the patterns may be an artefact of increasing sedimentation rates. The patterns are most pronounced in small billabongs, and due to their timing an early land use activity is again implicated. The historical data suggest that the aquatic macrophyte flora and associated fauna declined due to an early land use activity related to farming. It is likely that the change in redox occurred due to the decline in macrophytes, which lowered organic matter supply to the profundal zone. Furthermore, the persistence of depressed macrophyte levels, and continuing trends of changing relative abundance of some cladoceran species, suggest that the farming impacts are of the press variety, yet direct farming activity on the floodplain may have decreased this century. The macrophyte-free state may been maintained in large, deep billabongs, in spite of the removal of the disturbance agent, because of the existence of alternative stable states in the aquatic vegetation. Early farming may have caused the large, deep billabongs to switch from natural macrophyte dominance to natural phytoplankton dominance, as has been suggested to occur in shallow lakes in Europe. If so, it is quite likely that the decline of macrophytes in large, deep billabongs is reversible by temporarily lowering water levels in the spring time, and this would greatly benefit billabongs and the greater floodplain ecosystem. Once macrophyte beds are reestablished they should be stable unless further unnatural perturbations occur. If properly designed, attempts to restore macrophytes in billabongs can be used to test the hypothesis of alternative stable states in billabong vegetation, so that such attempts offer an opportunity to meld management and science in one project. This work demonstrates that even in ecosystems with high rates of turnover, events with return times on the order of centuries can have significant impacts on the ecosystem. Assessments of anthropogenic impacts to billabongs that do not include an historical component are likely to provide underestimates of the full impacts. While disturbance concepts appear to explain some of the patterns observed in the biota, other traits of the ecosystem (e.g. alternative stable states in the vegetation) may be required to explain the broad-scale patterns observed.
APA, Harvard, Vancouver, ISO, and other styles
49

Kellett, Richard Lawrence. "The two dimensional electric conductivity structure of the Southeast Australian continental margin." Phd thesis, 1989. http://hdl.handle.net/1885/145687.

Full text
APA, Harvard, Vancouver, ISO, and other styles
50

Robertson, K. E. "An electrical resistivity model of the southeast Australian lithosphere and asthenosphere." Thesis, 2012. http://hdl.handle.net/2440/95433.

Full text
Abstract:
This item is only available electronically.
A combination of magnetotelluric and geomagnetic depth sounding data were used to attempt to image the electrical resistivity structure of southeast Australia, to investigate the physical state of the crust and upper mantle. A 3D forward model of southeast Australia comprised of regional sets of broadband and long-period magnetotelluric and geomagnetic depth sounding data, over an area of 440 x 300 km2, was used to map broad-scale lithospheric properties. Model results show an order of magnitude decrease in resistivity from the depleted continental mantle lithosphere of the Delamerian Orogen in the west, to the more conducting oceanic mantle of the Lachlan Orogen in the east. The decrease in resistivity in conjunction with a 0.1 km/s decrease in P-wave velocity at depths of 50-250 km, suggest a change in temperature (_T_200_C) due to lithospheric thinning toward the east as the likely cause, in conjuction with a change in geochemistry and/or hydration. A high resolution two-dimensional inversion using data from 37 new and 39 existing broadband magnetotelluric stations mapped crustal heterogeneity beneath the Delamerian Orogen in much greater detail. Lateral changes in resistivity from 10-10 000 m occur over the space of a few kilometres. Low resistivity (_10 m) regions occur at depths of 10-40 km. Narrow paths of low resistivity extend to the surface, coinciding with locations of crustal faults from seismic interpretations. Movement of mantle up these faults, during periods of extension prior to the Delamerian Orogen, may have produced a carbon-rich, low resistivity lower crust, leaving a resistive upper mantle, depleted of volatiles.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Earth and Environmental Sciences, 2012
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography