Dissertations / Theses: 'Southeast Queensland'

1

Smith, Annette Deborah (Tam). "Archaeological spatial variability on Bribie Island, Southeast Queensland /." St. Lucia, Qld, 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17698.pdf.

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2

Gustafson, Johann A. "Hammerhead sharks (Sphyrnidae) of southeast Queensland: habitat and movements." Thesis, Griffith University, 2020. http://hdl.handle.net/10072/397639.

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Hammerhead sharks (Sphyrnidae) are iconic and charismatic species that have received little attention until more recently, resulting in knowledge gaps about life histories, habitats, behaviours and migratory drivers, mostly in the southern hemisphere such as Australian waters. Globally, shark populations are declining as many species extinction risk has increased under the threat of fishing and habitat degradation. Hammerhead shark (Sphyrnidae) populations are highly susceptible to human-induced pressure such as long lines and are currently undergoing severe declines, especially in Australia. Recently, hammerhead sharks have been added to the International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species, with scalloped hammerhead listed as critically endangered. Therefore, further information is needed to address the current shortfalls regarding hammerheads in Australia, for the management and conservation of these species. Earlier research using catch data from the Queensland Shark Control Program (QSCP) showed a decline in numbers of caught hammerhead sharks since the start of the program in 1960. A review of the literature (CHAPTER 1) revealed that hammerhead sharks were understudied in Australia, with information shortfalls on movement, resource use, nursery areas and habitat use. The general aim of this thesis was to provide a better understanding of the movement, distribution, habitat use and resource use of scalloped hammerhead shark (Sphyrna lewini) in Queensland, Australia to improve conservation and management strategies. I used multiple methodologies to determine (i) the distribution of suitable habitat for juvenile scalloped hammerhead sharks and the percentage of overlap with marine protected areas (CHAPTER 2); (ii) fine-scale movement of juvenile scalloped hammerheads within these habitats and determine behavioural states using high-resolution acoustic tracking (CHAPTER 3); (iii) thermal tolerance range “thermal niche” of hammerhead shark using historical catch records from the QSCP (CHAPTER 4); and (iv) resource overlap between hammerhead sharks species and with other co-existing large sharks using carbon and nitrogen stable isotopes (CHAPTER 5). This allowed me to build a solid baseline framework of the ecology of scalloped hammerhead sharks in Queensland. The species distribution model identified 10,082.87 km2 of suitable habitat characterised by low current velocities (< 0.5 m-s), warm sea surface temperatures (> 20°C), estuarine/oceanic salinities (25-35 PSU) and shallow bathymetries (< 20 m). Suitable habitats occurred in coastal areas within wetland and seagrass habitats. Highly suitable areas accounted for 1,784.33 km2 of the total distribution and ii occurred around highly developed areas, such as Moreton Bay, Hervey Bay, Townsville and Cairns. Coastal beach areas of the Gold Coast were also uncovered as highly suitable habitats and may be due to close proximity of the Gold Coast seaway and Tweed River connections to more sheltered estuarine habitats. The majority of the predicted suitable distribution occurred within the lower protection multi-use zones (6,291.20 km2) and outside marine protected areas (3,791.67 km2); where no-take zones protected only 11 % and 8.56 % of high and medium modelled suitable habitats. Within these habitats, continuous tracking of two juvenile scalloped hammerhead sharks uncovered highly active diving behaviours where both sharks continuously dove from water surface to the bay floor over 12- and 3-hour tracks. Two diving patterns were observed in both sharks and described as A-type: one long dive with multiple small dives at depth, and B-type dives: one long dive without extra dives at depth. The two-state behavioural model uncovered low activity (forage) and high activity (direction) states, which were influenced by distance to seagrass and coral habitats as well as habitat depth. Quantile regression modelling determined catches of hammerhead sharks in relation to changes in seas surface temperatures changed with latitude along the Queensland coast. Scalloped hammerhead catches in the southern areas were most likely to occur between 20℃ - 25℃ and likely to occur throughout the year in the northern areas, as sea surface temperatures remained above 22℃. Co-existing bull (Carcharias leucas) and tiger (Galeocerdo cuvier) sharks also occurred throughout this thermal range while white shark (Carcharodon carcharias) only occurred below 23℃. Stable isotope analysis revealed scalloped and great hammerhead sharks overlapped 69% in isotopic space and with several large shark species. Both hammerhead species undertook a seasonal dietary shift, and scalloped hammerheads showed a wider δ13C and lower δ15N than the more specialised great hammerhead. Tiger sharks feed at a lower trophic level overlapping mostly with both hammerhead sharks. White and bull sharks competed with hammerhead sharks at higher δ15N. Overall, results from my research make original contributions to the knowledge of hammerhead sharks by identifying previously unreported distributions of suitable juvenile habitats of the scalloped hammerhead, which occurred in developed areas and within multi-use protection zones. Additionally, the research described previously unreported diving patterns and state-switching of juvenile hammerhead sharks within highly developed areas, highlighting the importance of wetland and estuarine habitats for shark conservation. Furthermore, the research showed high overlap in resource use between two endangered hammerhead species with several large predatory shark species. In iii summary, this thesis highlights the relevance of movement and habitat use information in the conservation and management of endangered iconic shark species
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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3

Mackay, Stephen John. "Drivers of Macrophyte Assemblage Structure in Southeast Queensland Streams." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/367431.

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Recent drought and population growth along the east Australian coastline, combined with water quality issues and degradation of rivers of national significance, have focused attention on the importance of sustainable water resource use and maintenance of the ecological integrity of riverine ecosystems. Central to the development of stream management practices that minimise or ameliorate anthropogenic degradation of riverine ecosystems is an understanding of the principal drivers of ecosystem structure and function. This thesis investigates the principal drivers of submersed macrophyte assemblage structure in streams of southeast Queensland, Australia. Fundamental to this thesis is the development and testing of a conceptual model of macrophyte assemblage structure in streams with disturbance (hydrology and hydraulics) and resource availability (nitrogen, phosphorus, carbon, light) as the principal axes of the model. The suitability of the conceptual model as a framework to describe the key drivers of macrophyte assemblage structure within the study area was explored by testing hypotheses of macrophyte assemblage structure at various spatial scales across disturbance and resource availability gradients. In particular, it was hypothesised that assemblage structure could be described in terms of appropriate measures of disturbance and resource availability; that extremes of disturbance (e.g. flooding) and resource availability (e.g. high shade) would limit macrophyte growth; and that species richness would vary according to the intermediate disturbance hypothesis. Furthermore, it was expected that flow regime changes resulting from flow regulation would have predictable impacts on macrophyte assemblage structure, in line with these hypotheses. In general the results of this thesis supported hypotheses based on the conceptual model. Spatial and temporal patterns in macrophyte assemblage structure were associated with hydrologic-hydraulic and resource availability gradients. These patterns were shown to be consistent across a variety of spatial scales, but were tighter at the transect and hydraulic unit (riffle, run, pool) scales. The key descriptors of the disturbance axis of the conceptual model were bankfull shear stress, substrate stability, the coefficient of variation of mean daily discharge, days since last flood and the number of floods in the 12 months prior to sampling. Riparian canopy cover and alkalinity were identified as the key descriptors of the resource availability axis. However, geomorphological attributes such as bankfull depth and channel orientation were also important in structuring macrophyte assemblages. From the conceptual model it was predicted that flow regulation by large dams would result in increased macrophyte abundance due to reduced disturbance frequency and magnitude. Further, it was predicted that reduced temporal hydrologic variability in sites with regulated flows would produce relatively stable macrophyte assemblages as disturbance frequency (i.e. the frequency of biomass loss) should be minimal compared with an unregulated stream of similar morphology and water quality. These predictions were tested in two ways. Firstly, spatial patterns in assemblage structure were compared between regulated and unregulated sites. Flow regulation had no effect on species richness but macrophyte cover was higher than expected in regulated sites compared to macrophyte cover in unregulated reference sites. The extent of increase in macrophyte cover was dependent upon site location in the catchment, as hypothesised in the Serial Discontinuity Concept, and local (site-specific) characteristics. In the lower Brisbane River, the increase in macrophyte cover was relatively small as large macrophyte beds were natural features of this lowland river with limited riparian shading. In Yabba Creek, a mid-catchment tributary, the increase in macrophyte cover was relatively high, taking the form of extensive macrophyte beds which were uncommon in comparable (unregulated) streams characterised by high riparian canopy cover. Secondly, the effect of flow regulation on temporal variability in macrophyte assemblage structure was examined over a 12 month period in a regulated stream (Yabba Creek) and an adjacent unregulated stream (Amamoor Creek). The magnitude of temporal environmental variability was similar for both creeks. Macrophyte assemblage structure was found to be highly variable in Amamoor Creek, and comparatively stable in Yabba Creek, in accordance with conceptual model predictions. Again it was found that local habitat conditions in each waterway (particularly riparian shading) had an overriding influence on the response of submersed macrophytes to hydrologic variability and flow regulation. The effects of riparian shading on macrophyte assemblages were investigated further by examining the influence of riparian canopy cover and light availability on the growth of five aquatic macrophyte species in a stream rehabilitation site. This site was located in a second order headwater stream with a degraded riparian zone where unshaded parts of the site were infested with submersed and emergent macrophytes. Changes in assemblage structure were monitored over a two year period and related to changes in riparian canopy cover resulting from the regrowth of native riparian tubestock. Reductions in macrophyte abundance and changes in species composition were predicted from the conceptual model as riparian shade increased due to vegetation regrowth. The results are discussed in light of hypotheses derived from the conceptual model, particularly with respect to the effects of interactions between flow regulation and resource limitations on macrophyte assemblage structure. The results of this thesis show that the conceptual model is a valid representation of the physical habitat template occupied by submersed macrophytes in the study area, and is also likely to be valid for lotic ecosystems in other bioregions, provided that herbivory is not a major (alternative) source of disturbance. However, the contribution of hydrology as the principal direct driver of macrophyte assemblage structure is questioned. This thesis has shown that local (site-specific) conditions, including riparian canopy cover and substrate stability, are probably more important drivers of macrophyte assemblage structure per se than hydrology itself. Local habitat conditions such as bed stability and substrate composition determine how features of the flow regime, such as discharge magnitude, influence macrophyte assemblage structure. Management strategies that focus solely on manipulating the hydrologic regime (e.g. by provision of environmental flows) may not fully accommodate the habitat template for submersed macrophytes in lotic ecosystems.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
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4

Chern, Peter Kyaw Zaw Naing. "Patterns of coal sedimentation in the Ipswich Basin Southeast Queensland." Thesis, Queensland University of Technology, 2004. https://eprints.qut.edu.au/15924/1/Peter_Chern_Thesis.pdf.

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The intermontane Ipswich Basin, which is situated 30km south-west of Brisbane, contains coal measures formed in the Late Triassic Epoch following a barren non-depositional period. Coal, tuff, and basalt were deposited along with fluvial dominated sediments. The Ipswich Coal Measures mark the resumption of deposition in eastern Australia after the coal hiatus associated with a series of intense tectonic activity in Gondwanaland during the Permo-Triassic interval. A transtensional tectonic movement at the end of the Middle Triassic deformed the Toogalawah Group before extension led to the formation of the Carnian Ipswich Coal Measures in the east. The Ipswich Coal Measures comprise the Brassall and Kholo Subgroups. The Blackstone Formation, which forms the upper unit of the Brassall Subgroup, contains seven major coal seams. The lower unit of the Brassall Subgroup, the Tivoli Formation, consists of sixteen stratigraphically significant coal seams. The typical thickness of the Blackstone Formation is 240m and the Tivoli Formation is about 500m. The coal seams of the Ipswich Basin differ considerably from those of other continental Triassic basins. However, the coal geology has previously attracted little academic attention and the remaining exposures of the Ipswich coalfield are rapidly disappearing now that mining has ceased. The primary aim of this project was to study the patterns of coal sedimentation and the response of coal seam characteristics to changing depositional environments. The coal accumulated as a peat-mire in an alluvial plain with meandering channel systems. Two types of peat-mire expansion occurred in the basin. Peat-mire aggradation, which is a replacement of water body by the peatmire, was initiated by tectonic subsidence. This type of peat-mire expansion is known as terrestrialisation. It formed thick but laterally limited coal seams in the basin. Whereas, peat-mire progradation was related to paludification and produced widespread coal accumulation in the basin. The coal seams were separated into three main groups based on the mean seam thickness and aerial distribution of one-meter and four-meter thickness contour intervals. Group 1 seams within the one-meter thickness interval are up to 15,000m2 in area, and seams within the four-meter interval have an aerial extent of up to 10,000m2. Group 1A contains the oldest seam with numerous intraseam clastic bands and shows a very high thickness to area ratio, which indicates high subsidence rates. Group 1B seams have moderately high thickness to area ratios. The lower clastic influx and slower subsidence rates favoured peat-mire aggradation. The Group 1A seam is relatively more widespread in aerial extent than seams from Group 1B. Group 1C seams have low mean thicknesses and small areas, suggesting short-lived peat-mires as a result of high clastic influx. Group 2 seams arebetween 15,000 and 35,000m2 in area within the one-meter interval, and between 5,000 and 10,000m2 within the four-meter interval. They have moderately high area to thickness ratios, indicating that peat-mire expansion occurred due to progressively shallower accommodation and a rising groundwater table. Group 3 seams, which have aerial extents from 35,000 to 45,000m2 within the one-meter thickness contour interval and from 10,000 to 25,000m2 within the four-meter interval, show high aerial extent to thickness ratios. They were deposited in quiet depositional environments that favoured prolonged existence of peat-mires. Group 3 seams are all relatively young whereas most Group 1 seams are relatively old seams. All the major fault systems, F1, F2 and F3, trend northwest-southeast. Apart from the West Ipswich Fault (F3), the F1 and F2 systems are broad Palaeozoic basement structures and thus they may not have had a direct influence on the formation of the much younger coal measures. However, the sedimentation patterns appear to relate to these major fault systems. Depocentres of earlier seams in the Tivoli Formation were restricted to the northern part of the basin, marked by the F1 system. A major depocentre shift occurred before the end of the deposition of the Tivoli Formation as a result of subsidence in the south that conformed to the F2 system configuration. The Blackstone Formation depocentres shifted to the east (Depocentre 1) and west (Depocentre 2) simultaneously. This depocentre shift was associated with the flexural subsidence produced by the rejuvenation of the West Ipswich Fault. Coal accumulation mainly occurred in Depocentre 1. Two types of seam splitting occurred in the Ipswich Basin. Sedimentary splitting or autosedimentation was produced by frequent influx of clastic sediments. The fluvial dominant depositional environments created the random distribution of small seam splits. However, the coincidence of seam splits and depocentres found in some of the seams suggests tectonic splitting. Furthermore, the progressive splitting pattern, which displays seam splits overlapping, was associated with continued basin subsidence. The tectonic splitting pattern is more dominant in the Ipswich Basin. Alternating bright bands shown in the brightness profiles are a result of oscillating water cover in the peat-mire. Moderate groundwater level, which was maintained during the development of the peat, reduced the possibility of salinisation and drowning of the peat swamp. On the other hand, a slow continuous rise of the groundwater table, that kept pace with the vertical growth of peat, prevented excessive oxidation of peat. Ipswich coal is bright due to its high vitrinite content. The cutinite content is also high because the dominant flora was pteridosperms of Dicroidium assemblage containing waxy and thick cuticles. Petrographic study revealed that the depositional environment was telmatic with bog forest formed under ombrotrophic to mesotrophic hydrological conditions. The high preservation of woody or structured macerals such as telovitrinite and semifusinite indicates that coal is autochthonous. The high mineral matter content in coal is possibly due to the frequent influx of clastic and volcanic sediments. The Ipswich Basin is part of a much larger Triassic basin extending to Nymboida in New South Wales. Little is known of the coal as it lacks exposures. It is apparently thin to absent except in places like Ipswich and Nymboida. This study suggests that the dominant control on depocentres of thick coal at Ipswich has been the tectonism. Fluvial incursions and volcanism were superimposed on this.

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5

Chern, Peter Kyaw Zaw Naing. "Patterns of Coal Sedimentation in the Ipswich Basin Southeast Queensland." Queensland University of Technology, 2004. http://eprints.qut.edu.au/15924/.

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The intermontane Ipswich Basin, which is situated 30km south-west of Brisbane, contains coal measures formed in the Late Triassic Epoch following a barren non-depositional period. Coal, tuff, and basalt were deposited along with fluvial dominated sediments. The Ipswich Coal Measures mark the resumption of deposition in eastern Australia after the coal hiatus associated with a series of intense tectonic activity in Gondwanaland during the Permo-Triassic interval. A transtensional tectonic movement at the end of the Middle Triassic deformed the Toogalawah Group before extension led to the formation of the Carnian Ipswich Coal Measures in the east. The Ipswich Coal Measures comprise the Brassall and Kholo Subgroups. The Blackstone Formation, which forms the upper unit of the Brassall Subgroup, contains seven major coal seams. The lower unit of the Brassall Subgroup, the Tivoli Formation, consists of sixteen stratigraphically significant coal seams. The typical thickness of the Blackstone Formation is 240m and the Tivoli Formation is about 500m. The coal seams of the Ipswich Basin differ considerably from those of other continental Triassic basins. However, the coal geology has previously attracted little academic attention and the remaining exposures of the Ipswich coalfield are rapidly disappearing now that mining has ceased. The primary aim of this project was to study the patterns of coal sedimentation and the response of coal seam characteristics to changing depositional environments. The coal accumulated as a peat-mire in an alluvial plain with meandering channel systems. Two types of peat-mire expansion occurred in the basin. Peat-mire aggradation, which is a replacement of water body by the peatmire, was initiated by tectonic subsidence. This type of peat-mire expansion is known as terrestrialisation. It formed thick but laterally limited coal seams in the basin. Whereas, peat-mire progradation was related to paludification and produced widespread coal accumulation in the basin. The coal seams were separated into three main groups based on the mean seam thickness and aerial distribution of one-meter and four-meter thickness contour intervals. Group 1 seams within the one-meter thickness interval are up to 15,000m2 in area, and seams within the four-meter interval have an aerial extent of up to 10,000m2. Group 1A contains the oldest seam with numerous intraseam clastic bands and shows a very high thickness to area ratio, which indicates high subsidence rates. Group 1B seams have moderately high thickness to area ratios. The lower clastic influx and slower subsidence rates favoured peat-mire aggradation. The Group 1A seam is relatively more widespread in aerial extent than seams from Group 1B. Group 1C seams have low mean thicknesses and small areas, suggesting short-lived peat-mires as a result of high clastic influx. Group 2 seams arebetween 15,000 and 35,000m2 in area within the one-meter interval, and between 5,000 and 10,000m2 within the four-meter interval. They have moderately high area to thickness ratios, indicating that peat-mire expansion occurred due to progressively shallower accommodation and a rising groundwater table. Group 3 seams, which have aerial extents from 35,000 to 45,000m2 within the one-meter thickness contour interval and from 10,000 to 25,000m2 within the four-meter interval, show high aerial extent to thickness ratios. They were deposited in quiet depositional environments that favoured prolonged existence of peat-mires. Group 3 seams are all relatively young whereas most Group 1 seams are relatively old seams. All the major fault systems, F1, F2 and F3, trend northwest-southeast. Apart from the West Ipswich Fault (F3), the F1 and F2 systems are broad Palaeozoic basement structures and thus they may not have had a direct influence on the formation of the much younger coal measures. However, the sedimentation patterns appear to relate to these major fault systems. Depocentres of earlier seams in the Tivoli Formation were restricted to the northern part of the basin, marked by the F1 system. A major depocentre shift occurred before the end of the deposition of the Tivoli Formation as a result of subsidence in the south that conformed to the F2 system configuration. The Blackstone Formation depocentres shifted to the east (Depocentre 1) and west (Depocentre 2) simultaneously. This depocentre shift was associated with the flexural subsidence produced by the rejuvenation of the West Ipswich Fault. Coal accumulation mainly occurred in Depocentre 1. Two types of seam splitting occurred in the Ipswich Basin. Sedimentary splitting or autosedimentation was produced by frequent influx of clastic sediments. The fluvial dominant depositional environments created the random distribution of small seam splits. However, the coincidence of seam splits and depocentres found in some of the seams suggests tectonic splitting. Furthermore, the progressive splitting pattern, which displays seam splits overlapping, was associated with continued basin subsidence. The tectonic splitting pattern is more dominant in the Ipswich Basin. Alternating bright bands shown in the brightness profiles are a result of oscillating water cover in the peat-mire. Moderate groundwater level, which was maintained during the development of the peat, reduced the possibility of salinisation and drowning of the peat swamp. On the other hand, a slow continuous rise of the groundwater table, that kept pace with the vertical growth of peat, prevented excessive oxidation of peat. Ipswich coal is bright due to its high vitrinite content. The cutinite content is also high because the dominant flora was pteridosperms of Dicroidium assemblage containing waxy and thick cuticles. Petrographic study revealed that the depositional environment was telmatic with bog forest formed under ombrotrophic to mesotrophic hydrological conditions. The high preservation of woody or structured macerals such as telovitrinite and semifusinite indicates that coal is autochthonous. The high mineral matter content in coal is possibly due to the frequent influx of clastic and volcanic sediments. The Ipswich Basin is part of a much larger Triassic basin extending to Nymboida in New South Wales. Little is known of the coal as it lacks exposures. It is apparently thin to absent except in places like Ipswich and Nymboida. This study suggests that the dominant control on depocentres of thick coal at Ipswich has been the tectonism. Fluvial incursions and volcanism were superimposed on this.

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6

Morrison, Fiona Clare, and n/a. "Altitudinal Variation in the Life History of Anurans in Southeast Queensland." Griffith University. School of Environmental and Applied Science, 2002. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20031125.120847.

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Global declines and disappearances of amphibians from high altitude, pristine habitats have been reported in recent years. To date the cause of many of these declines and/or disappearances has not been identified. Although it is well documented that life history characteristics of temperate amphibians are influenced by altitude (due to systematic variation of temperature with altitude), little work has been carried out on the effects of altitude on Australian anurans. This lack of ecological data is a major impediment to identifying the causal factors responsible for amphibian declines. Due to differences in life history characteristics, high altitude populations may be less resilient than their lowland counterparts and subsequently may be more vulnerable to extinction. Consequently, the main aim of this study was to determine whether altitude influenced life history characteristics and ultimately population resilience of anurans in the southeast Queensland region. Six anuran species; Litoria chloris, L. lesueuri, L. pearsoniana (Anura: Hylidae), Mixophyes fasciolatus, M. fleayi and M. iteratus (Anura: Myobatrachidae) were studied over three field seasons (1997-1999) in 18 sites of varying altitude (100-950m) in the southeast Queensland region. The life history characteristics examined were: activity and breeding season length, fecundity and egg size, number of clutches produced per season, tadpole growth and development rates, longevity, age at maturity, reproductive life span, average lifetime fecundity, survival and recapture rates. The data were collected using a combination of field-based surveys (body sizes, clutch sizes, and survival and recapture rates), museum specimen dissections (clutch and egg sizes), reciprocal transplant field experiments (tadpole growth and development rates) and skeletochronology (longevity, age at maturity, reproductive lifespan and average lifetime fecundity). On average, high altitude populations of all species had shorter breeding and activity seasons than low altitude populations (up to 10 weeks less in some cases). The magnitude of the difference in breeding season length varied among years depending on the average temperature and rainfall for the year; i.e. differences appeared greater in warmer and wetter years. Within a population males had longer breeding and activity seasons than females. Although breeding season length varied with altitude, the number of nights that individuals were active within the breeding season did not vary; i.e. low altitude populations were not active for more nights despite having a longer breeding season. This result was attributed to the absence of a relationship between individual activity and environmental variables (air temperature, rainfall, etc.) in many of the populations. Generally, intraspecific clutch size did not vary significantly with altitude. This result was due to the absence of a significant relationship between female body size and altitude (as clutch size is proportional to female body size). Egg size also did not vary with altitude however, suggesting egg size may be canalized (i.e. fixed) in these species. Results also suggest that females of these species only produce one clutch of eggs per season. Interspecific differences in reproductive characteristics largely reflected differences in reproductive mode, larval habitat and female body size. Altitude negatively influenced growth and development rates in L. chloris and development rates in L. pearsoniana. Tadpoles raised at high altitudes were also generally larger at each Gosner Development Stage in both species. The results of the reciprocal transplant experiments suggested that most of the variation in growth and development rates was due to environmental factors (water temperature) rather than genetic or maternal factors. Altitude or genetic factors did not significantly affect tadpole survival in either species. The results suggest that tadpoles occurring at high altitudes take longer to reach metamorphosis and do so at a larger size than their lowland counterparts. With the exception of L. lesueuri, skeletochronology was suitable for age estimation in the study species. Altitude had a significant effect on the age at maturity or longevity in some of the species, however there were trends toward older individuals and older ages at maturity in high altitude populations for the remaining species. Females were generally older than males for all species and in the case of longer-lived species (i.e. Mixophyes spp.) also tended to be older when breeding for the first time. The large overlap of body sizes of individuals of different ages demonstrates that body size is a poor indicator of age in these species. This is the first study to estimate average lifetime fecundity for more than one amphibian species and/or population. The results suggest that the absence of significant altitudinal variation in the average lifetime fecundity of different populations is due to tradeoffs made by females (current reproduction vs. survival). There was no significant altitudinal variation in annual survival and recapture rates in any of the species, and generally there was no difference in the survival and recapture rates of males and females in each population. Within a year, monthly survival and recapture rates were more variable at low than high altitudes and this was attributed to the longer breeding season of low altitude populations. The results did not support previous studies that suggested there was a size bias in survival and recapture rates. The shorter breeding seasons, slower growth and development rates, older age at maturity and greater longevity found in the high altitude study populations will result in increased generation time in those populations. In turn, increased generation time can cause high altitude populations to be less resilient (i.e. population takes longer to return to equilibrium after a disturbance away from equilibrium) (Pimm et al. 1988, Pimm 1991) and ultimately more vulnerable or prone to extinction or decline. The majority of unexplained global amphibian declines have occurred at high altitudes in tropical and subtropical areas. These latitudinal patterns may be explained by the narrow range of environmental tolerances exhibited by tropical organisms resulting in mountains being effectively higher in the tropics. Consequently, high altitude tropical species are likely to be even more vulnerable than temperate species occurring at similar altitudes. Further work on the effects of geographic variation, especially interactions between altitude and latitude are needed to evaluate the hypotheses for the causes of these declines and disappearances.

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7

Parker, Nathaniel Ryan. "Assessing the effectiveness of water sensitive urban design in Southeast Queensland." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/34119/1/Nathaniel_Parker_Thesis.pdf.

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Water Sensitive Urban Design (WSUD) systems have the potential mitigate the hydrologic disturbance and water quality concerns associated with stormwater runoff from urban development. In the last few years WSUD has been strongly promoted in South East Queensland (SEQ) and new developments are now required to use WSUD systems to manage stormwater runoff. However, there has been limited field evaluation of WSUD systems in SEQ and consequently knowledge of their effectiveness in the field, under storm events, is limited. The objective of this research project was to assess the effectiveness of WSUD systems installed in a residential development, under real storm events. To achieve this objective, a constructed wetland, bioretention swale and a bioretention basin were evaluated for their ability to improve the hydrologic and water quality characteristics of stormwater runoff from urban development. The monitoring focused on storm events, with sophisticated event monitoring stations measuring the inflow and outflow from WSUD systems. Data analysis undertaken confirmed that the constructed wetland, bioretention basin and bioretention swale improved the hydrologic characteristics by reducing peak flow. The bioretention systems, particularly the bioretention basin also reduced the runoff volume and frequency of flow, meeting key objectives of current urban stormwater management. The pollutant loads were reduced by the WSUD systems to above or just below the regional guidelines, showing significant reductions to TSS (70-85%), TN (40-50%) and TP (50%). The load reduction of NOx and PO4 3- by the bioretention basin was poor (<20%), whilst the constructed wetland effectively reduced the load of these pollutants in the outflow by approximately 90%. The primary reason for the load reduction in the wetland was due to a reduction in concentration in the outflow, showing efficient treatment of stormwater by the system. In contrast, the concentration of key pollutants exiting the bioretention basin were higher than the inflow. However, as the volume of stormwater exiting the bioretention basin was significantly lower than the inflow, a load reduction was still achieved. Calibrated MUSIC modelling showed that the bioretention basin, and in particular, the constructed wetland were undersized, with 34% and 62% of stormwater bypassing the treatment zones in the devices. Over the long term, a large proportion of runoff would not receive treatment, considerably reducing the effectiveness of the WSUD systems.

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8

Morrison, Fiona Clare. "Altitudinal Variation in the Life History of Anurans in Southeast Queensland." Thesis, Griffith University, 2002. http://hdl.handle.net/10072/366730.

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Abstract:

Global declines and disappearances of amphibians from high altitude, pristine habitats have been reported in recent years. To date the cause of many of these declines and/or disappearances has not been identified. Although it is well documented that life history characteristics of temperate amphibians are influenced by altitude (due to systematic variation of temperature with altitude), little work has been carried out on the effects of altitude on Australian anurans. This lack of ecological data is a major impediment to identifying the causal factors responsible for amphibian declines. Due to differences in life history characteristics, high altitude populations may be less resilient than their lowland counterparts and subsequently may be more vulnerable to extinction. Consequently, the main aim of this study was to determine whether altitude influenced life history characteristics and ultimately population resilience of anurans in the southeast Queensland region. Six anuran species; Litoria chloris, L. lesueuri, L. pearsoniana (Anura: Hylidae), Mixophyes fasciolatus, M. fleayi and M. iteratus (Anura: Myobatrachidae) were studied over three field seasons (1997-1999) in 18 sites of varying altitude (100-950m) in the southeast Queensland region. The life history characteristics examined were: activity and breeding season length, fecundity and egg size, number of clutches produced per season, tadpole growth and development rates, longevity, age at maturity, reproductive life span, average lifetime fecundity, survival and recapture rates. The data were collected using a combination of field-based surveys (body sizes, clutch sizes, and survival and recapture rates), museum specimen dissections (clutch and egg sizes), reciprocal transplant field experiments (tadpole growth and development rates) and skeletochronology (longevity, age at maturity, reproductive lifespan and average lifetime fecundity). On average, high altitude populations of all species had shorter breeding and activity seasons than low altitude populations (up to 10 weeks less in some cases). The magnitude of the difference in breeding season length varied among years depending on the average temperature and rainfall for the year; i.e. differences appeared greater in warmer and wetter years. Within a population males had longer breeding and activity seasons than females. Although breeding season length varied with altitude, the number of nights that individuals were active within the breeding season did not vary; i.e. low altitude populations were not active for more nights despite having a longer breeding season. This result was attributed to the absence of a relationship between individual activity and environmental variables (air temperature, rainfall, etc.) in many of the populations. Generally, intraspecific clutch size did not vary significantly with altitude. This result was due to the absence of a significant relationship between female body size and altitude (as clutch size is proportional to female body size). Egg size also did not vary with altitude however, suggesting egg size may be canalized (i.e. fixed) in these species. Results also suggest that females of these species only produce one clutch of eggs per season. Interspecific differences in reproductive characteristics largely reflected differences in reproductive mode, larval habitat and female body size. Altitude negatively influenced growth and development rates in L. chloris and development rates in L. pearsoniana. Tadpoles raised at high altitudes were also generally larger at each Gosner Development Stage in both species. The results of the reciprocal transplant experiments suggested that most of the variation in growth and development rates was due to environmental factors (water temperature) rather than genetic or maternal factors. Altitude or genetic factors did not significantly affect tadpole survival in either species. The results suggest that tadpoles occurring at high altitudes take longer to reach metamorphosis and do so at a larger size than their lowland counterparts. With the exception of L. lesueuri, skeletochronology was suitable for age estimation in the study species. Altitude had a significant effect on the age at maturity or longevity in some of the species, however there were trends toward older individuals and older ages at maturity in high altitude populations for the remaining species. Females were generally older than males for all species and in the case of longer-lived species (i.e. Mixophyes spp.) also tended to be older when breeding for the first time. The large overlap of body sizes of individuals of different ages demonstrates that body size is a poor indicator of age in these species. This is the first study to estimate average lifetime fecundity for more than one amphibian species and/or population. The results suggest that the absence of significant altitudinal variation in the average lifetime fecundity of different populations is due to tradeoffs made by females (current reproduction vs. survival). There was no significant altitudinal variation in annual survival and recapture rates in any of the species, and generally there was no difference in the survival and recapture rates of males and females in each population. Within a year, monthly survival and recapture rates were more variable at low than high altitudes and this was attributed to the longer breeding season of low altitude populations. The results did not support previous studies that suggested there was a size bias in survival and recapture rates. The shorter breeding seasons, slower growth and development rates, older age at maturity and greater longevity found in the high altitude study populations will result in increased generation time in those populations. In turn, increased generation time can cause high altitude populations to be less resilient (i.e. population takes longer to return to equilibrium after a disturbance away from equilibrium) (Pimm et al. 1988, Pimm 1991) and ultimately more vulnerable or prone to extinction or decline. The majority of unexplained global amphibian declines have occurred at high altitudes in tropical and subtropical areas. These latitudinal patterns may be explained by the narrow range of environmental tolerances exhibited by tropical organisms resulting in mountains being effectively “higher” in the tropics. Consequently, high altitude tropical species are likely to be even more vulnerable than temperate species occurring at similar altitudes. Further work on the effects of geographic variation, especially interactions between altitude and latitude are needed to evaluate the hypotheses for the causes of these declines and disappearances.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental and Applied Science
Science, Environment, Engineering and Technology
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9

Mohd, Abdullah Maizah. "Ecological Studies of the Mangrove-Associated Meiofauna in Southeast Queensland, Australia." Thesis, Griffith University, 2016. http://hdl.handle.net/10072/367507.

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Abstract:

Meiofauna are ubiquitous but poorly-studied components of soft-bottom marine communities around the world, including mangroves. However, information on the ecological role of the meiofauna in subtropical intertidal habitats is scarce compared to knowledge of the benthic macrofauna. The dynamic environmental conditions and heterogeneous sediments of mangroves present challenges to understanding the structure of mangrove meiofaunal assemblages at various spatial and temporal scales. This study was designed to elucidate the ecological role of the meiofauna in mangroves by studying their three main ecological elements: 1) assemblages structure; 2) top-down interaction with macrofauna; and 3) bottom-up interaction in terms of nutrient utilisation. Firstly, how meiofaunal assemblage respond to estuarine sediment conditions was described by analysing the assemblages associated with different mangrove species (Avicennia marina, Rhizophora stylosa and Aegiceras corniculatum) at three locations in sub-tropical Southeast Queensland, Australia. Secondly, the significance and nature of top-down control on the density of meiofauna based on their interactions with deposit- feeding crabs was investigated in a mangrove and the adjoining sandflat.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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10

Felemban, Ohood Othman. "Infection Prevention and Control Programs in Community-Based Home Visiting Nursing in Southeast Queensland, Australia: A Case Study." Thesis, Griffith University, 2015. http://hdl.handle.net/10072/367412.

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Abstract:

In Australia, healthcare settings are required to obtain and maintain formal accreditation by the Australian Council on Health Care Standards. One area of this accreditation is infection prevention and control. In addition to accreditation, healthcare settings are required to appoint an infection control professional to coordinate the local infection control programs. In addition to these requirements, healthcare settings in Queensland are required by law to implement an infection control management plan and take reasonable precautions to minimise the risk of Healthcare-Associated Infections [HAIs] through the identification of the infection risks and measures to be taken to prevent or minimise these risks. Such efforts must be consistent with relevant national infection control guidelines for healthcare settings. The National Health and Medical Research Council [NHMRC] published the Australian Guidelines for the Prevention and Control of Infection in Healthcare in which they established six key elements of a successful infection prevention and control program. The NHMRC guidelines are considered to be fundamental because they are based on the best available evidence and address the critical aspects of infection prevention and control in healthcare settings. The NHMRC guidelines are hospital-based. Donabedian’s theory was used as a conceptual structure for this study. The structure, processes and outcome strategies of infection prevention and control programs in CBHVN was explored in each organisation. The findings reveal that infection prevention and control programs were informally structured in CBHVN
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Nursing and Midwifery
Griffith Health
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11

Buck, Adrian. "The Mt. Marcella volcanics : middle Triassic convergent margin volcanism in Southeast Queensland." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/20171/1/Adrian_Buck_Thesis.pdf.

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Abstract:

Triassic igneous rocks in southeast Queensland show a number of subduction related geochemical characteristics. Extensive calc-alkalic granitoids chains characterise the region and define the ancient arc setting. Despite good evidence that an arc was present, Triassic volcanic rocks are relatively sparse in southeast Queensland. The Mt Marcella Volcanics, of the northern Esk Trough are a previously poorly understood piece of the Middle Triassic convergent margin of southeast Queensland. A three stage model is proposed for the eruptive development of the Middle Triassic (245- 230Ma) volcanic succession that involves; 1) The Middle Triassic basalt, comprising coalesced lava flows covering as much as 500km2 with an estimated eruptive volume in the order of 50km3. 2) The Penwhaupell Volcanic Centre, a concentration of inter-bedded lavas and pyroclastic rocks dominated by dacite that forms a volcanic pile exceeding 2km stratigraphic thickness and representing an eruptive volume of approximately 48km3. 3) The Ettiewyn Caldera, representing the catastrophic culmination of the Mt Marcella Volcanics event, with a sequence of caldera out-flow and in-fill andesite ignimbrites and post-caldera lavas with a total eruptive volume in the order of 130km3. The “Penwhaupell Volcanic Centre” and the “Ettiewyn Caldera” are two new sub-divisions and the proposed names, for the lower and upper sequences of the previously undifferentiated Mt Marcella Volcanics. The Mt Marcella Volcanics magma compositions show cogenetic characteristics that define three evolutionary pathways; 1) a mildly alkali series, from basaltic-andesite to trachy-dacite related through fractionation dominated by plagioclase and clinopyroxene 2) an amphibole series, basaltic-andesite to hornblende dacite through fractionation dominated by plagioclase and hornblende under hydrous conditions, and 3) a pyroxene series, from basaltic-andesite to pyroxene andesite through fractionation dominated by plagioclase and pyroxene. Quantitative petrogenetic models generally support the proposed fractional crystallisation pathway, however weaknesses are acknowledged, with good results for the major elements and REE off-set by generally poor results for the LILE. Despite the inconclusive trace element results for the modelled fractionation, strong geochemical similarities and cogenetic relationships have been established. A typical arc-like geochemical signature including a pronounced Nb depletion characterises the Mt Marcella Volcanics. However, the geochemical character within the Middle Triassic volcanic succession reveals an unusual transition from an OIB character of the Middle Triassic basalts, to the Andean arc character of later Mt Marcella Volcanics. The implications of this could have profound impact on our understanding of how southeast Queensland’s Triassic tectonic setting operated by providing support for hotspot activity rather than subduction-driven activity.

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12

Buck, Adrian. "The Mt. Marcella volcanics : middle Triassic convergent margin volcanism in Southeast Queensland." Queensland University of Technology, 2008. http://eprints.qut.edu.au/20171/.

Full text

Abstract:

Triassic igneous rocks in southeast Queensland show a number of subduction related geochemical characteristics. Extensive calc-alkalic granitoids chains characterise the region and define the ancient arc setting. Despite good evidence that an arc was present, Triassic volcanic rocks are relatively sparse in southeast Queensland. The Mt Marcella Volcanics, of the northern Esk Trough are a previously poorly understood piece of the Middle Triassic convergent margin of southeast Queensland. A three stage model is proposed for the eruptive development of the Middle Triassic (245- 230Ma) volcanic succession that involves; 1) The Middle Triassic basalt, comprising coalesced lava flows covering as much as 500km2 with an estimated eruptive volume in the order of 50km3. 2) The Penwhaupell Volcanic Centre, a concentration of inter-bedded lavas and pyroclastic rocks dominated by dacite that forms a volcanic pile exceeding 2km stratigraphic thickness and representing an eruptive volume of approximately 48km3. 3) The Ettiewyn Caldera, representing the catastrophic culmination of the Mt Marcella Volcanics event, with a sequence of caldera out-flow and in-fill andesite ignimbrites and post-caldera lavas with a total eruptive volume in the order of 130km3. The “Penwhaupell Volcanic Centre” and the “Ettiewyn Caldera” are two new sub-divisions and the proposed names, for the lower and upper sequences of the previously undifferentiated Mt Marcella Volcanics. The Mt Marcella Volcanics magma compositions show cogenetic characteristics that define three evolutionary pathways; 1) a mildly alkali series, from basaltic-andesite to trachy-dacite related through fractionation dominated by plagioclase and clinopyroxene 2) an amphibole series, basaltic-andesite to hornblende dacite through fractionation dominated by plagioclase and hornblende under hydrous conditions, and 3) a pyroxene series, from basaltic-andesite to pyroxene andesite through fractionation dominated by plagioclase and pyroxene. Quantitative petrogenetic models generally support the proposed fractional crystallisation pathway, however weaknesses are acknowledged, with good results for the major elements and REE off-set by generally poor results for the LILE. Despite the inconclusive trace element results for the modelled fractionation, strong geochemical similarities and cogenetic relationships have been established. A typical arc-like geochemical signature including a pronounced Nb depletion characterises the Mt Marcella Volcanics. However, the geochemical character within the Middle Triassic volcanic succession reveals an unusual transition from an OIB character of the Middle Triassic basalts, to the Andean arc character of later Mt Marcella Volcanics. The implications of this could have profound impact on our understanding of how southeast Queensland’s Triassic tectonic setting operated by providing support for hotspot activity rather than subduction-driven activity.

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13

Campbell, Lorraine M. "Basin analysis and tectonic evolution of the Esk Trough in southeast Queensland /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18382.pdf.

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14

Jackson, Joanne M. "Hydrogeology and groundwater flow model, central catchment of Bribie Island, Southeast Queensland." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/18347/1/Joanne_M._Jackson_Thesis.pdf.

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Abstract:

Bribie Island is a large, heterogeneous, sand barrier island that contains groundwater aquifers of commercial and environmental significance. Population growth has resulted in expanding residential developments and consequently increased demand for water. Caboolture Shire Council (CSC) has proposed to increase groundwater extraction by a new borefield. Two aquifers exist within the Quaternary sandmass which are separated by an indurated sand layer that is ubiquitous in the area. A shallow aquifer occurs in the surficial, clean sands and is perched on the indurated sands. Water levels in the shallow water table aquifer follow the topography and groundwater occurs under unconfined conditions in this system. A basal aquifer occurs beneath the indurated sands, which act as a semi-confining layer in the island system. The potentiometric surface of the basal aquifer occurs as a gentle groundwater mound. The shallow groundwater system supports water-dependent ecosystems including wetlands, native woodlands and commercial pine plantations. Excessive groundwater extraction could lower the water table in the shallow aquifer to below the root depth of vegetation on the island. Groundwater discharge along the coastline is essential to maintain the position of the saline water - fresh groundwater boundary in this island aquifer system. Any activity that changes the volume of fresh water discharge or lowers the water table or potentiometric surface below sea level will result in a consequent change in the saline water – freshwater interface and could lead to saline water intrusion. Groundwater level data was compared with the residual rainfall mass curve (RRMC) on hydrographs, which revealed that the major trends in groundwater levels are related to rainfall. Bribie Island has a sub-tropical climate, with a mean annual rainfall of around 1358mm/year (Bongaree station). Mean annual pan evaporation is around 1679mm/year and estimates of the potential evapotranspiration rates range from 1003 to 1293mm/year. Flows from creeks, the central swale and groundwater discharged from the area have the potential to affect water quality within the tidal estuary, Pumicestone Passage. Groundwater within the island aquifer system is fresh with electrical conductivity ranging from 61 to 1018ìS/cm while water near the coast, canals or tidal creeks is brackish to saline (1596 to 34800ìS/cm). Measurements of pH show that all groundwater is acidic to slightly acidic (3.3-6.6), the lower values are attributed to the breakdown of plant material into organic acids. Groundwater is dominated by Na-Cl type water, which is expected in a coastal island environment with Na-Cl rainfall. Some groundwater samples possess higher concentrations of calcium and bicarbonate ions, which could be due to chemical interactions with buried shell beds while water is infiltrating to depth and due to the longer residence times of groundwater in the basal aquifer. A steady-state, sub-regional groundwater flow model was developed using the Visual MODFLOW computer package. The 4 layer, flow model simulated the existing hydrogeological system and the dominant groundwater processes controlling groundwater flow. The numerical model was calibrated against existing data and returned reasonable estimates of groundwater levels and hydraulic parameters. The model illustrated that: .. The primary source of groundwater recharge is infiltration of rainfall for the upper, perched aquifer (Layer 1). Recharge for the lower sand layers is via vertical leakage from the upper, perched aquifer, through the indurated sands (Layers 2 and 3) to the semi-confined, basal aquifer (Layer 4). .. The dominant drainage processes on Bribie Island are evapotranspiration (15070m3/day) and groundwater seepage from the coast, canals and tidal creeks (9512m3/day). Analytical calculations using Darcy’s Law estimated that approximately 8000m3/day of groundwater discharges from central Bribie Island, approximately 16% less than the model. .. As groundwater flows preferentially toward the steepest hydraulic gradient, the main direction of horizontal groundwater flow is expected to be along an eastwest axis, towards either the central swale or the coastline. The central swale was found to act as a groundwater sink in the project area.

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15

Jackson, Joanne M. "Hydrogeology and groundwater flow model, central catchment of Bribie Island, Southeast Queensland." Queensland University of Technology, 2007. http://eprints.qut.edu.au/18347/.

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Abstract:

Bribie Island is a large, heterogeneous, sand barrier island that contains groundwater aquifers of commercial and environmental significance. Population growth has resulted in expanding residential developments and consequently increased demand for water. Caboolture Shire Council (CSC) has proposed to increase groundwater extraction by a new borefield. Two aquifers exist within the Quaternary sandmass which are separated by an indurated sand layer that is ubiquitous in the area. A shallow aquifer occurs in the surficial, clean sands and is perched on the indurated sands. Water levels in the shallow water table aquifer follow the topography and groundwater occurs under unconfined conditions in this system. A basal aquifer occurs beneath the indurated sands, which act as a semi-confining layer in the island system. The potentiometric surface of the basal aquifer occurs as a gentle groundwater mound. The shallow groundwater system supports water-dependent ecosystems including wetlands, native woodlands and commercial pine plantations. Excessive groundwater extraction could lower the water table in the shallow aquifer to below the root depth of vegetation on the island. Groundwater discharge along the coastline is essential to maintain the position of the saline water - fresh groundwater boundary in this island aquifer system. Any activity that changes the volume of fresh water discharge or lowers the water table or potentiometric surface below sea level will result in a consequent change in the saline water – freshwater interface and could lead to saline water intrusion. Groundwater level data was compared with the residual rainfall mass curve (RRMC) on hydrographs, which revealed that the major trends in groundwater levels are related to rainfall. Bribie Island has a sub-tropical climate, with a mean annual rainfall of around 1358mm/year (Bongaree station). Mean annual pan evaporation is around 1679mm/year and estimates of the potential evapotranspiration rates range from 1003 to 1293mm/year. Flows from creeks, the central swale and groundwater discharged from the area have the potential to affect water quality within the tidal estuary, Pumicestone Passage. Groundwater within the island aquifer system is fresh with electrical conductivity ranging from 61 to 1018ìS/cm while water near the coast, canals or tidal creeks is brackish to saline (1596 to 34800ìS/cm). Measurements of pH show that all groundwater is acidic to slightly acidic (3.3-6.6), the lower values are attributed to the breakdown of plant material into organic acids. Groundwater is dominated by Na-Cl type water, which is expected in a coastal island environment with Na-Cl rainfall. Some groundwater samples possess higher concentrations of calcium and bicarbonate ions, which could be due to chemical interactions with buried shell beds while water is infiltrating to depth and due to the longer residence times of groundwater in the basal aquifer. A steady-state, sub-regional groundwater flow model was developed using the Visual MODFLOW computer package. The 4 layer, flow model simulated the existing hydrogeological system and the dominant groundwater processes controlling groundwater flow. The numerical model was calibrated against existing data and returned reasonable estimates of groundwater levels and hydraulic parameters. The model illustrated that: .. The primary source of groundwater recharge is infiltration of rainfall for the upper, perched aquifer (Layer 1). Recharge for the lower sand layers is via vertical leakage from the upper, perched aquifer, through the indurated sands (Layers 2 and 3) to the semi-confined, basal aquifer (Layer 4). .. The dominant drainage processes on Bribie Island are evapotranspiration (15070m3/day) and groundwater seepage from the coast, canals and tidal creeks (9512m3/day). Analytical calculations using Darcy’s Law estimated that approximately 8000m3/day of groundwater discharges from central Bribie Island, approximately 16% less than the model. .. As groundwater flows preferentially toward the steepest hydraulic gradient, the main direction of horizontal groundwater flow is expected to be along an eastwest axis, towards either the central swale or the coastline. The central swale was found to act as a groundwater sink in the project area.

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16

Hansen, James W. L. "The petrology, geochemistry and petrogenesis of the Goomboorian intrusive complex, southeast Queensland." Thesis, Queensland University of Technology, 1997.

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17

Kelly, Gregory. "Development of a Sustainability Index for Local Roads in Southeast Queensland, Australia." Thesis, Griffith University, 2022. http://hdl.handle.net/10072/415807.

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Abstract:

A high-quality transportation system is a necessity in a modern economy. The road network is a common, and perhaps the most significant, component of a transportation system and an essential part of all modern economies. Road systems are developed to enable the safe movement of passenger vehicles and freight at reasonable speed. Meeting this objective is essential for an efficient economy. A functional road network is not only an important part of the transportation system but also an expensive investment. Good policy requires that infrastructure investment should provide a return on the investment. This investment warrants judicious management to ensure the infrastructure is maintained in a cost-effective manner. This study proposed and developed the concept of a new Sustainability Index for Roads (SIR) using the three pillars of sustainability namely, economic, social and environmental. The reasons for implementing an index solely for roads are: to minimise the cost of road rehabilitation (has a high ongoing cost) (economic); involve the community (has little knowledge to make informed decisions) (social); and, to reduce the environmental impact of annual road rehabilitation programs across Australia (environmental). This SIR provides an alternative approach to determine the optimal future target Pavement Condition Index (PCI) for a local government authority (LGA). The newly developed SIR includes a community consultation option to make a more informed decision when choosing a future target PCI. This decision involves balancing the community’s expectations (social pillar) regarding the annual road rehabilitation budget (economic pillar) with particular reference to the return on investment (ROI) for their annual road budget and both the financial and environmental costs (environmental pillar) of the different pavement design options for the rehabilitation of roads. This study also produced a new tool for estimating the Return on Investment for the local government that provided their data for this study, for the rehabilitation of their road network. The study also provided a transparent low-cost method, to engage community representatives to consider what the community was willing to fund, using the ROI as above. The study also investigated the two most common road rehabilitation design types that incur different environmental impacts, from the local government works program. The study demonstrated that there is a difference in the environmental harm caused by the different road rehabilitation designs and that this difference can be shown in terms of costs to be incurred. The SIR developed in this study equips the community with the knowledge to make informed decisions about the pavement condition and environmental harm they are willing to fund, paving the way for better road management by the relevant authority. The SIR is the community’s chosen Pavement Condition Index (PCI) after consideration the new ROI curve (Future PCI Versus annual Budgets) relative to the achieved PCI is an alternative road network specific measure of asset sustainability to the current Queensland ASR.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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18

Besar, Sa'aid Hafizah. "The Adoption of Health Technology Assessment (HTA) in Selected Southeast Queensland Hospitals." Thesis, Griffith University, 2014. http://hdl.handle.net/10072/367692.

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Abstract:

New health technologies are undoubtedly one of the most significant contributors in improving health and quality of life. Nonetheless, they also create challenges in ensuring they provide value for money and that they are safe and effective. In order to address these issues, health technology assessment (HTA) processes have been developed. Today, HTA has become an essential tool for making decisions about choosing and introducing new health technologies. However, concern has been expressed about HTA dissemination and use by decision makers especially at the institutional level. There is little published research to date from the HTA users’ point of view in this area of concern. Thus, this study aims to investigate the effectiveness of the dissemination of HTA products at the institutional level using the diffusion of innovation theory supplemented by the promoting action on research implementation in health services (PARIHS) framework as the research conceptual framework in order to determine the major determinants. These determinants include the decision making processes for introducing new health technologies, and the organisational and individual factors that contribute to the adoption processes in hospitals.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Public Health
Griffith Health
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19

Sharma, Suman. "Population Structure and Phylogeography of Four Freshwater Species in Southeast Queensland, Australia." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/365400.

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Freshwater species are expected to show higher levels of genetic structuring than those inhabiting estuarine or marine environments because it is difficult for freshwater species to move between river systems. However, freshwater species that exhibit some tolerance to salt water may be capable of marine dispersal and therefore may show lower levels of genetic structuring. The species that are restricted to freshwater are likely to have genetic structures that reflect the history of those drainages. Various studies have attempted to use genetic data to infer past geomorphological changes. For example, stream rearrangements were thought to have influenced the distribution of genetic diversity in the purple spotted Gudgeon, Morgunda morgunda (Hurwood and Hughes, 1998). The main aim of this study was to resolve the relative significance of contemporary and historical events in structuring populations of freshwater species in southeast Queensland river systems. The study revolved around four freshwater species namely the ornate rainbow fish Rhadinocentrus ornatus, the empire gudgeon Hypseleotris compressa, the endemic freshwater shrimp Macrobrachium australiense and freshwater shrimp Macrobrachium tolmerum, and examined patterns of genetic variation using allozyme and mtDNA analysis and also previously established hypotheses of biogeographic association among these regions was tested. It was hypothesized that R. ornatus and M. australiense, which are restricted to freshwater, would display genetic structure similar to the species which had already been examined i.e., would show similarities among streams along the Sunshine Coast region only (Hughes et al., 1999), because these creeks were thought to have had a confluence before they reached the sea, during the last 10, 000 BP. The results for R. ornatus and M. australiense, were different from expectations, In contrast to earlier studies, there was evidence of restricted gene flow among sites within the Sunshine Coast region based on highly significant FST values. This was a surprising finding but suggested that gene flow among subpopulations is extremely limited in these two species in both past and present times. The high levels of genetic structure in R. ornatus and M. australiense suggest that they may have different dispersal behaviour from the previously studied species Oxleyan Pygmy Perch (Nannoperca oxleyana) (Hughes et al., 1998), even though they inhabit the same environment. The apparent difference between these two obligate freshwater species and Oxleyan Pygmy Perch (N. oxleyana) studies may be because R. ornatus and M. australiense may not have moved between adjacent streams even though they shared a confluence. Other reasons could be that they may also be more sensitive to elevated salinities than Oxleyan Pygmy Perch (N. oxleyana). These elevated salinities would have occurred at the lower reaches of the streams and thus could have restricted dispersal from one creek to the other for these two obligate freshwater species (R. ornatus and M. australiense). It was hypothesized that H. compressa and M. tolmerum would show lower levels of genetic structure than R. ornatus and M. australiense throughout the study areas because they can tolerate some marine conditions (Chapter 3 & 4). Genetic data for H. compressa supported this hypothesis, indicating that subpopulations of this species had low levels of mtDNA genetic differentiation, with many recently derived haplotypes which were widespread along the southeast Queensland coast. This suggested that there was existing gene flow among and between regions or recent demographic change in the populations sampled. On the other hand, genetic data on M. tolmerum did not support this hypothesis completely, because although allozyme analysis suggested gene flow between regions, mtDNA data suggested that gene flow was limited. The study demonstrated the importance of current and past events in shaping the genetic population structure of freshwater species of southeast Queensland river systems. The species that were thought to tolerate brackish water showed higher levels of connectivity among rivers than those that were restricted to freshwater, although M. tolmerum showed lower levels of connectivity than predicted. For R. ornatus and M. australiense, both contemporary and historical movements are extremely limited across the region. To conclude, the present study showed that R. ornatus and M. australiense have a genetic structure typical of freshwater species. On the other hand, H. compressa had a genetic structure more typical of estuarine or marine species, while M. tolmerum, had a pattern intermediate between freshwater and estuarine species.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental Studies
Science, Environment, Engineering and Technology
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20

Harbison, John Edwin. "Groundwater chemistry and hydrological processes within a Quaternary coastal plain: Pimpama, Southeast Queensland." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16647/1/John%20Harbison%20Thesis.pdf.

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The Pimpama estuarine plain in subtropical southeast Queensland is comprised of Quaternary sediments infilling older bedrock. These multilayered unconsolidated sediments have various depositional origins, and are highly heterogeneous. The plain is low-lying and the surface drainage is controlled by flood mitigation measures including tidal gates and channelised streams. The control of surface drainage potentially affects the shallow water table. This modification of hydrology has implications for future viability of agriculture and also the environmental health of waterways. Increased landscape modification and water management is likely in the coming years. The combination of sediment heterogeneity, low hydraulic gradients, and artificial drainage modification result in the plain being hydrogeologically complex. In order to understand hydrologic processes in this setting, a multi-disciplinary research programme was conducted which included a drilling program, overland electromagnetic induction and other geophysical surveys (downhole gamma log, electromagnetic induction and magnetic susceptibility) to initially establish the geologic framework. These surveys were followed by hydrogeochemical testing which includes for major and minor ions and also stable isotopes, and mineralogical analysis of drillhole material. Underlying basement rock occurs at up to 60 m depth. Unconsolidated gravel and sand deposits occur within incised paleo-valleys and are overlain by predominantly low-permeability fluvial sandy clays and estuarine and lagoonal muds. Fine-grained delta sands occur in the top 15 m of the sub-surface. Within the unconsolidated sediments, hydrodynamic trends clearly discriminated between upper unconfined and lower semi-confined aquifer systems. A comparison of surface water and shallow groundwater levels indicate limited interaction of groundwater and surface water. Hydrogeochemical analysis effectively distinguished between groundwater bodies, and also distinguished saline groundwater from seawater. Trends in major ion chemistry in the semi-confined system (particularly Na/Cl and Ca/Cl ratios) showed ion exchange accompanying saline intrusion. However, due to factors such as mineral dissolution, major ion chemistry does not clearly identify solute flux trends in the shallow aquifer system. Water stable isotope analysis (δ18O and δ2H) indicated the provenance of fresh and saline groundwater and also the relative importance of the principal hydrologic processes, i.e. evaporation and water uptake by plants. Groundwater exhibited a wide range in salinity, from very fresh to hypersaline. The formation of hypersaline groundwater was attributed largely to uptake of water by mangrove forests. Since mangrove forests were more extensive at the time of the Holocene maximum sea level (approximately 6,000 years ago) than at present, some of this groundwater may represent relict salinity from this earlier time. The relationship of relict salinity to low permeability sediments, particularly at intermediate depths, and their depositional history was examined. Vertical salinity gradients and hydrogeochemistry within these sediments varied according to position within the plain, suggesting deposition under various hydrological and sea level regimes. A preliminary investigation using analysis of stable sulfate isotopes (δ34S and δ18OSO4) was made. This study shows substantial potential for the application of this technique for quantification of solute flux and sulfur chemical transformations within settings such as this coastal plain. To establish shallow groundwater flow processes, a MODFLOW-based numerical model was used to inversely estimate aquifer parameters under various recharge scenarios. The model was designed to examine the relative importance of evapotranspiration and discharge to surface waters. However, largely due to the complexity of the drainage network and non-uniform surface water flows, the quantification of surface water- groundwater interaction by consideration of hydrodynamics is problematic. Therefore, the chemistry of groundwater and surface water was compared. While the estimated contribution of rainfall to groundwater level fluctuations was significant (46%), high evapotranspiration rates reduced net recharge and it was concluded that baseflow to drains and creeks during dry periods was insignificant, and groundwater velocities in the shallow aquifer are low. The study illustrates the value of both hydrodynamic and hydrogeochemical analyses in estuarine settings where relict salinity and groundwater-aquifer interactions impact significantly on water quality. Saline groundwater is chemically distinct from theoretical mixtures of seawater and freshwater. The study also demonstrates the value of particular chemical parameters, e.g. Na/Cl and SO4/Cl ratios and stable water isotopes, for identifying hydrologic processes in this setting.

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21

Harbison, John Edwin. "Groundwater chemistry and hydrological processes within a Quaternary coastal plain: Pimpama, Southeast Queensland." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16647/.

Full text

Abstract:

The Pimpama estuarine plain in subtropical southeast Queensland is comprised of Quaternary sediments infilling older bedrock. These multilayered unconsolidated sediments have various depositional origins, and are highly heterogeneous. The plain is low-lying and the surface drainage is controlled by flood mitigation measures including tidal gates and channelised streams. The control of surface drainage potentially affects the shallow water table. This modification of hydrology has implications for future viability of agriculture and also the environmental health of waterways. Increased landscape modification and water management is likely in the coming years. The combination of sediment heterogeneity, low hydraulic gradients, and artificial drainage modification result in the plain being hydrogeologically complex. In order to understand hydrologic processes in this setting, a multi-disciplinary research programme was conducted which included a drilling program, overland electromagnetic induction and other geophysical surveys (downhole gamma log, electromagnetic induction and magnetic susceptibility) to initially establish the geologic framework. These surveys were followed by hydrogeochemical testing which includes for major and minor ions and also stable isotopes, and mineralogical analysis of drillhole material. Underlying basement rock occurs at up to 60 m depth. Unconsolidated gravel and sand deposits occur within incised paleo-valleys and are overlain by predominantly low-permeability fluvial sandy clays and estuarine and lagoonal muds. Fine-grained delta sands occur in the top 15 m of the sub-surface. Within the unconsolidated sediments, hydrodynamic trends clearly discriminated between upper unconfined and lower semi-confined aquifer systems. A comparison of surface water and shallow groundwater levels indicate limited interaction of groundwater and surface water. Hydrogeochemical analysis effectively distinguished between groundwater bodies, and also distinguished saline groundwater from seawater. Trends in major ion chemistry in the semi-confined system (particularly Na/Cl and Ca/Cl ratios) showed ion exchange accompanying saline intrusion. However, due to factors such as mineral dissolution, major ion chemistry does not clearly identify solute flux trends in the shallow aquifer system. Water stable isotope analysis (δ18O and δ2H) indicated the provenance of fresh and saline groundwater and also the relative importance of the principal hydrologic processes, i.e. evaporation and water uptake by plants. Groundwater exhibited a wide range in salinity, from very fresh to hypersaline. The formation of hypersaline groundwater was attributed largely to uptake of water by mangrove forests. Since mangrove forests were more extensive at the time of the Holocene maximum sea level (approximately 6,000 years ago) than at present, some of this groundwater may represent relict salinity from this earlier time. The relationship of relict salinity to low permeability sediments, particularly at intermediate depths, and their depositional history was examined. Vertical salinity gradients and hydrogeochemistry within these sediments varied according to position within the plain, suggesting deposition under various hydrological and sea level regimes. A preliminary investigation using analysis of stable sulfate isotopes (δ34S and δ18OSO4) was made. This study shows substantial potential for the application of this technique for quantification of solute flux and sulfur chemical transformations within settings such as this coastal plain. To establish shallow groundwater flow processes, a MODFLOW-based numerical model was used to inversely estimate aquifer parameters under various recharge scenarios. The model was designed to examine the relative importance of evapotranspiration and discharge to surface waters. However, largely due to the complexity of the drainage network and non-uniform surface water flows, the quantification of surface water- groundwater interaction by consideration of hydrodynamics is problematic. Therefore, the chemistry of groundwater and surface water was compared. While the estimated contribution of rainfall to groundwater level fluctuations was significant (46%), high evapotranspiration rates reduced net recharge and it was concluded that baseflow to drains and creeks during dry periods was insignificant, and groundwater velocities in the shallow aquifer are low. The study illustrates the value of both hydrodynamic and hydrogeochemical analyses in estuarine settings where relict salinity and groundwater-aquifer interactions impact significantly on water quality. Saline groundwater is chemically distinct from theoretical mixtures of seawater and freshwater. The study also demonstrates the value of particular chemical parameters, e.g. Na/Cl and SO4/Cl ratios and stable water isotopes, for identifying hydrologic processes in this setting.

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22

Hodgkinson, Jane Helen. "Geological control of physiography in Southeast Queensland: A multi-scale analysis using GIS." Thesis, Queensland University of Technology, 2009. https://eprints.qut.edu.au/29968/1/Jane_Hodgkinson_Thesis.pdf.

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Abstract:

The study reported here, constitutes a full review of the major geological events that have influenced the morphological development of the southeast Queensland region. Most importantly, it provides evidence that the region’s physiography continues to be geologically ‘active’ and although earthquakes are presently few and of low magnitude, many past events and tectonic regimes continue to be strongly influential over drainage, morphology and topography. Southeast Queensland is typified by highland terrain of metasedimentary and igneous rocks that are parallel and close to younger, lowland coastal terrain. The region is currently situated in a passive margin tectonic setting that is now under compressive stress, although in the past, the region was subject to alternating extensional and compressive regimes. As part of the investigation, the effects of many past geological events upon landscape morphology have been assessed at multiple scales using features such as the location and orientation of drainage channels, topography, faults, fractures, scarps, cleavage, volcanic centres and deposits, and recent earthquake activity. A number of hypotheses for local geological evolution are proposed and discussed. This study has also utilised a geographic information system (GIS) approach that successfully amalgamates the various types and scales of datasets used. A new method of stream ordination has been developed and is used to compare the orientation of channels of similar orders with rock fabric, in a topologically controlled approach that other ordering systems are unable to achieve. Stream pattern analysis has been performed and the results provide evidence that many drainage systems in southeast Queensland are controlled by known geological structures and by past geological events. The results conclude that drainage at a fine scale is controlled by cleavage, joints and faults, and at a broader scale, large river valleys, such as those of the Brisbane River and North Pine River, closely follow the location of faults. These rivers appear to have become entrenched by differential weathering along these planes of weakness. Significantly, stream pattern analysis has also identified some ‘anomalous’ drainage that suggests the orientations of these watercourses are geologically controlled, but by unknown causes. To the north of Brisbane, a ‘coastal drainage divide’ has been recognized and is described here. The divide crosses several lithological units of different age, continues parallel to the coast and prevents drainage from the highlands flowing directly to the coast for its entire length. Diversion of low order streams away from the divide may be evidence that a more recent process may be the driving force. Although there is no conclusive evidence for this at present, it is postulated that the divide may have been generated by uplift or doming associated with mid-Cenozoic volcanism or a blind thrust at depth. Also north of Brisbane, on the D’Aguilar Range, an elevated valley (the ‘Kilcoy Gap’) has been identified that may have once drained towards the coast and now displays reversed drainage that may have resulted from uplift along the coastal drainage divide and of the D’Aguilar blocks. An assessment of the distribution and intensity of recent earthquakes in the region indicates that activity may be associated with ancient faults. However, recent movement on these faults during these events would have been unlikely, given that earthquakes in the region are characteristically of low magnitude. There is, however, evidence that compressive stress is building and being released periodically and ancient faults may be a likely place for this stress to be released. The relationship between ancient fault systems and the Tweed Shield Volcano has also been discussed and it is suggested here that the volcanic activity was associated with renewed faulting on the Great Moreton Fault System during the Cenozoic. The geomorphology and drainage patterns of southeast Queensland have been compared with expected morphological characteristics found at passive and other tectonic settings, both in Australia and globally. Of note are the comparisons with the East Brazilian Highlands, the Gulf of Mexico and the Blue Ridge Escarpment, for example. In conclusion, the results of the study clearly show that, although the region is described as a passive margin, its complex, past geological history and present compressive stress regime provide a more intricate and varied landscape than would be expected along typical passive continental margins. The literature review provides background to the subject and discusses previous work and methods, whilst the findings are presented in three peer-reviewed, published papers. The methods, hypotheses, suggestions and evidence are discussed at length in the final chapter.

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23

Hodgkinson, Jane Helen. "Geological control of physiography in Southeast Queensland : a mult-scale analysis using GIS." Queensland University of Technology, 2009. http://eprints.qut.edu.au/29968/.

Full text

Abstract:

The study reported here, constitutes a full review of the major geological events that have influenced the morphological development of the southeast Queensland region. Most importantly, it provides evidence that the region’s physiography continues to be geologically ‘active’ and although earthquakes are presently few and of low magnitude, many past events and tectonic regimes continue to be strongly influential over drainage, morphology and topography. Southeast Queensland is typified by highland terrain of metasedimentary and igneous rocks that are parallel and close to younger, lowland coastal terrain. The region is currently situated in a passive margin tectonic setting that is now under compressive stress, although in the past, the region was subject to alternating extensional and compressive regimes. As part of the investigation, the effects of many past geological events upon landscape morphology have been assessed at multiple scales using features such as the location and orientation of drainage channels, topography, faults, fractures, scarps, cleavage, volcanic centres and deposits, and recent earthquake activity. A number of hypotheses for local geological evolution are proposed and discussed. This study has also utilised a geographic information system (GIS) approach that successfully amalgamates the various types and scales of datasets used. A new method of stream ordination has been developed and is used to compare the orientation of channels of similar orders with rock fabric, in a topologically controlled approach that other ordering systems are unable to achieve. Stream pattern analysis has been performed and the results provide evidence that many drainage systems in southeast Queensland are controlled by known geological structures and by past geological events. The results conclude that drainage at a fine scale is controlled by cleavage, joints and faults, and at a broader scale, large river valleys, such as those of the Brisbane River and North Pine River, closely follow the location of faults. These rivers appear to have become entrenched by differential weathering along these planes of weakness. Significantly, stream pattern analysis has also identified some ‘anomalous’ drainage that suggests the orientations of these watercourses are geologically controlled, but by unknown causes. To the north of Brisbane, a ‘coastal drainage divide’ has been recognized and is described here. The divide crosses several lithological units of different age, continues parallel to the coast and prevents drainage from the highlands flowing directly to the coast for its entire length. Diversion of low order streams away from the divide may be evidence that a more recent process may be the driving force. Although there is no conclusive evidence for this at present, it is postulated that the divide may have been generated by uplift or doming associated with mid-Cenozoic volcanism or a blind thrust at depth. Also north of Brisbane, on the D’Aguilar Range, an elevated valley (the ‘Kilcoy Gap’) has been identified that may have once drained towards the coast and now displays reversed drainage that may have resulted from uplift along the coastal drainage divide and of the D’Aguilar blocks. An assessment of the distribution and intensity of recent earthquakes in the region indicates that activity may be associated with ancient faults. However, recent movement on these faults during these events would have been unlikely, given that earthquakes in the region are characteristically of low magnitude. There is, however, evidence that compressive stress is building and being released periodically and ancient faults may be a likely place for this stress to be released. The relationship between ancient fault systems and the Tweed Shield Volcano has also been discussed and it is suggested here that the volcanic activity was associated with renewed faulting on the Great Moreton Fault System during the Cenozoic. The geomorphology and drainage patterns of southeast Queensland have been compared with expected morphological characteristics found at passive and other tectonic settings, both in Australia and globally. Of note are the comparisons with the East Brazilian Highlands, the Gulf of Mexico and the Blue Ridge Escarpment, for example. In conclusion, the results of the study clearly show that, although the region is described as a passive margin, its complex, past geological history and present compressive stress regime provide a more intricate and varied landscape than would be expected along typical passive continental margins. The literature review provides background to the subject and discusses previous work and methods, whilst the findings are presented in three peer-reviewed, published papers. The methods, hypotheses, suggestions and evidence are discussed at length in the final chapter.

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24

Stanley, Glenda. "Aspirations of Pacific Island High School Students for University Study in Southeast Queensland." Thesis, Griffith University, 2020. http://hdl.handle.net/10072/397043.

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Abstract:

Although Australia is a nation of great opportunity, this is not always the case for many Pacific high school students from low socio economic status (low-SES) backgrounds in Logan City, Australia. Many Pacific Island young people continue to be under-represented in tertiary education and over-represented in low skilled, low paid employment (Kearney & Glen, 2017; Ravulo, 2015, 2018, 2019; Ravulo, Said, Micsko, & Purchase, 2020). This qualitative study explored the lives and experiences of Pacific high school students that shaped their (a) aspirations for university study, (b) pursuit of these aspirations, and (c) participation at university. Thirty-one students participated in six semi-structured year-level-specific focus groups referred to as talanoa circles. Of this group, eight students participated in semi-structured interviews three years later which provided rich data on their lived experiences that supported, or not, their participation at university. Van Manen’s (1990) phenomenological approach was applied to better understand the essences of participants’ lived experiences. It also examined the relationships and experiences influencing student aspirations, aligned with Bronfenbrenner’s (1995, 2005) bioecological model. The study found that while participants aspired to attend university to fulfil their parents’ migrant dream, their sense of responsibility to the collective group, more specifically their family and community, outweighed their aspirations. This greatly influenced the decisions and pathways young people pursued on completion of high school, many times at the expense of their participation at university. The learnings from this study contribute to the very limited literature on Pacific high school students’ experiences in Australia and adds to the body of knowledge available on the influences of aspiration for Pacific students. It also provides practical contributions for families, schools/universities and government to better support more positive outcomes for Pacific young people.
Thesis (Professional Doctorate)
Doctor of Education (EdD)
School Educ & Professional St
Arts, Education and Law
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25

Stock, Daniel. "The Dynamics of Lantana Camara (L.)Invasion of Subtropical Rainforest in Southeast Queensland." Thesis, Griffith University, 2005. http://hdl.handle.net/10072/366732.

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Abstract:

Lantana Lantana camara L. is a highly aggressive exotic environmental weed that is weestablished throughout eastern Australia and is reportedly able to displace native vegetation under a range of conditions. Whether lantana is able to displace native vegetation in the absence of anthropogenic disturbance is subject of some disagreement in the literature. The question remains, however, as to what is the future for the Gold Coast hinterland rainforests in the face of invasion by lantana? This study is mainly directed at addressing the dynamics at the lantana/rainforest interface, especially lantana's capacity to invade and ability to compete with the wetter subtropical rainforests of the MacPherson Ranges of southeast Queensland, where the studies are centered on the Springbrook Plateau and the Springbrook and Lamington National Parks. The aims of this research are to determine: whether lantana can displace rainforest; whether rainforest can reclaim the space lost to lantana; and what are the mechanisms and processes involved. To investigate these questions a conceptual framework was determined where key processes at the rainforest/lantana interface were determined and set in a logical context. A wide variety of possible processes whereby lantana could resist or displace rainforest or forest could resist or replace lantana were identified. The framework questions were addressed by observations made at lantana patches in Springbrook and Lamington National Parks in southeast Queensland. These answers/conclusions indicate that lantana is not invading further into intact rainforest and is seemingly isolated to canopy gaps, suggesting that rainforest is suppressing further expansion of lantana. Even though lantana may not commonly occur thriving in subtropical rainforest, it was determined that the issues/interactions that need to be pursued via experimentation were as follows: (i) how common is lantana in the national parks of southeast Queensland; (ii) what limits lantana expansion (is it physical shading, processes attributable to biological effects, such as allelopathy or a combination of both) and; (iii) what physical/biological conditions suppress lantana health and aggressiveness. Although some previous work has looked at the correlation between lantana density and tree cover in dry rainforest and savanna woodland, there have been no reported studies looking specifically at the quantity and abundance of lantana throughout a forest community. An extensive transect study in subtropical rainforest in southeast Queensland assessed habitat variables and the density of the lantana at numerous points along four transects running through rainforest and other mesic communities. The study was conducted in national parks to ensure that the typical disturbances present were, as much as possible natural rather than anthropogenic. From this study the extent of lantana infestation in particular forest types was determined and forest variables such as canopy density and canopy type were compared with lantana density providing indications of the current extent of infestation and the types of forest especially prone to infestation by this environmental weed. The density of lantana in intact rainforest was low and only slightly more lantana was observed in secondary forest than in primary forest. These differences are however driven by the density of the forest rather then the nature of the forest. Finally, lantana appears to be disturbance-dependent in that there is significantly more lantana in disturbed areas than undisturbed areas of the forest: these differences were attributable to the more open canopies above disturbed sites, rather than the disturbance itself. According to previous work the germination of lantana seeds is significantly reduced in low light conditions, such as occur under intact rainforest. A germination experiment investigated the contributions of shading and canopy type to the germination of lantana seeds. The experiment permitted the separation of shading and species-specific effects and the study of rainforest seeds under lantana. Seeds were bagged and placed under rainforest canopy trees and lantana, above and below the leaf litter for a six-month period or until maximum likely germination was achieved. The amount of germination was compared with the amount of shading, the position relative to leaf litter and the species of canopy they were placed under, to determine the relative contributions of shading, litter cover and canopy species. The results of this study show that native rainforest seeds germinate differently under rainforest canopies than under lantana with most showing a higher level of germination under rainforest canopies. This difference was found to be attributable to both the nature of the canopy (canopy species) and the changing level of shading (canopy openness). For most rainforest species, the difference attributable to the level of shading and nature of the canopy was indicative of greater germination capacity under the rainforest canopy than under lantana. Thus, lantana reduces the germination of natives and therefore, in this manner, reduces the forest's capacity to replace lantana. Lantana seed did not germinate in this study and thus their capacity to out-compete native species is, based on this work, unknown. It appears that the competitive ability of lantana seedlings may gives them the edge over rainforest seedlings when colonising canopy gaps. It is therefore important to examine the survival and growth of lantana seedlings compared to rainforest seedlings and the effect of canopy species and shade levels on lantana seedling survival, growth and thus competitive ability. Lantana and rainforest seedlings were planted under rainforest trees and lantana, and their survival and rate of growth over a period of 24 months compared. The survival and rate of growth was compared with the amount of shading and the species under which the seedlings were planted, to determine the contributions of shading and canopy species to survival and growth. The results of this study suggest that, as a seedling, lantana survival was greater under secondary forest canopies and lantana, than under the primary forest species. The growth of lantana seedlings was significantly different under different forest canopies, but differences in growth were not attributable to the different canopy openness ranges with each canopy species and better explained by the actual canopy species themselves. This suggests that there aren canopy specific differences in seedling growth beyond that explicable by canopy openness. As a canopy, lantana does not appear to suppress the survival and growth of rainforest seedlings and thus as a canopy, lantana may not prevent the establishment of native forest seedlings that were studied here. In the rainforests of southeast Queensland, lantana is able to maintain large and dense patches apparently for long periods, leaving open the question of whether lantana in these forests is able to displace the forest or whether the rainforest displaces lantana. In this study, lantana was observed in a number of different locations in the border ranges between New South Wales and Queensland and there is little evidence of its capacity to displace forests in the absence of additional disturbances. The study here explored the reasons for the apparent inability of lantana to displace forest and focused particularly on the shading of lantana by the forest and the capacity of forest species to grow through patches of lantana. Lantana's inability to successfully expand its patch size, under intact rainforest, appears to be due to two main reasons: (i) the increased level of shade provided by the intact canopy of the rainforest compared to the open canopy of the disturbance; and (ii) the particular nature of (species in) the intact rainforest. The results suggest that lantana has little capacity to adapt to shading, only developing slightly larger leaves, longer petioles and longer thinner internodes in moderate shade. Conversely, there is a marked degradation of most health characteristics when lantana is growing in low light conditions. Where the canopy is denser than 75%, lantana will be unthrifty, probably unable to grow and certainly unable to flower. Therefore, maintaining at least 75% shading should prevent the successful encroachment of lantana and early achievement of this level of canopy density should be aimed at in revegetating disturbed sites. This thesis suggests that lantana does not appear to have the ability to competitively displace rainforest. Conversely reclaiming the land taken over by lantana is very slow. More research is required to fully understand the rainforest's ability to recolonise lantana infestations. Although lantana thrives in the canopy gaps created by disturbances, it appears to be restricted (to these gaps) and seems unable to expand the patch beyond the canopy gap. If rainforest reclamation can be confirmed to take place at such a pace that gaps can be closed in an ecologically reasonable time, little active control of lantana maybe required. If active intervention is desired then control efforts should focus on the physical removal of the lantana from initially, small gaps, accompanied by the planting of fast growing rainforest species that can increase the shade at a disturbed site to prevent the reestablishment of the weed.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental and Applied Science
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26

Oh, Yan-Nam Erwin. "Geotechnical and Ground Improvement Aspects of Motorway Embankments in Soft Clay, Southeast Queensland." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/367085.

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Abstract:

This dissertation is the first Geotechnical Engineering doctoral thesis in Griffith University, and a detail study of the soft clay as encountered in Southeast Queensland is carried out. In the study process, due to the insufficient laboratory equipments and access to Geotechnical softwares, the dissertation has to be presented in a practical format. In addition, laboratory tests were conducted to investigate the application of chemical (cement and lime) treatments. Three case histories (Sunshine Motorway, Port of Brisbane Motorway, and Gold Coast Highway) are presented in this thesis. The main focuses are on the following aspects: i) soil parameters needed in engineering design from laboratory tests and field measurement, ii) the behaviour of constructed embankment on soft ground with and without ground improvement, iii) the performance of ground improvement techniques. The methods which have been employed to achieve the main aims were conventional methods. Laboratory test data and field measurement data, which were utilised for back-analyses and prediction of constructed embankment of soft ground behaviours, were obtained from QDMR. Thick layer of soft sensitive marine clay were found in the studied areas with up to 13m depth. The performance behaviour of constructed embankment on Southeast Queensland soft clay deposit has been evaluated based on the interpretation of test data, the theoretical analyses and conventional methods for settlement, lateral displacement, and excess pore pressure dissipation. Detail study of the estuarine soft clay as encountered in the Sunshine Motorway is carried out. 33 borehole data were examined to delineate the soft clay profile, which is about 10.5m thickness and varies substantially along the longitudinal section of the motorway. The laboratory value of the coefficient of volume decrease ranged from 1 to 5 MN/m2 and the laboratory values of the coefficient of consolidation are in the range of 0.25 to 0.5 m2/year. The Port of Brisbane Motorway embankments are installed with vertical drains and consist of three sections. Embankment A had drains at 3 meter spacing, and Embankments B and C had drains at 1.5 meter spacings. The maximum settlement obtained after 226 days of monitoring is shown. It can be seen that vertical drain treatment significantly increased final settlement. This increase varied from 70 to 80%. It can be concluded from the settlement results that vertical drains would have increased rate of consolidation. A trial embankment was constructed along the Gold Coast Highway. This embankment was divided into three sections, one section contained no ground improvement, and the other two sections had stone columns at 2m spacing and 3m spacing. For embankment with 3m spacing, the maximum settlement was 490 mm. For embankment with 2m spacing, the maximum settlement was 386 mm. For embankment without stone column, the maximum settlement was 522 mm. Based on the laboratory tests, for cement treated samples with 5 percent to 15 percent cement content, the maximum unconfined compressive strength increased from 132 kPa to 370 kPa for 7 days curing period; these values for 28days curing increased from 170 kPa to 405 kPa. For lime treated samples with lime contents from 2 percent to 15 percent, the maximum unconfined compressive strength increases from 47 kPa to 199 kPa (for 7 days curing period). Results indicated that, 2 percent lime has little effect on peak unconfined compressive strength. This thesis summarises some ground improvement techniques used in Southeast Queensland, and demonstrated the applicable of chemical stabilisation. Overall it was concluded that the addition of cement and lime has favourable effects on the strength characteristics of Southeast Queensland soft clays.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
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27

Davies, Sara Ellen. "Legitimising rejection : international refugee law in Southeast Asia /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19072.pdf.

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Phan, Ha Thi Thu. "Mapping of shallow coastal groundwaters, their hydrology and environmental geochemistry : Pumicestone catchment, Southeast Queensland." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/49165/1/Ha_Thi_Thu_Phan_Thesis.pdf.

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Abstract:

Blooms of the toxic cyanobacterium majuscula Lyngbya in the coastal waters of southeast Queensland have caused adverse impacts on both environmental health and human health, and on local economies such as fishing and tourism. A number of studies have confirmed that the main limiting nutrients (“nutrients of concern”) that contribute to these blooms area Fe, DOC, N, P and also pH. This study is conducted to establish the distribution of these parameters in a typical southeast Queensland coastal setting. The study maps the geochemistry of shallow groundwater in the mainland Pumicestone catchment with an emphasis on the nutrients of concern to understand how these nutrients relate to aquifer materials, landuse and anthropogenic activities. The results of the study form a GIS information layer which will be incorporated into a larger GIS model being produced by Queensland Department of Environment and Resource Management (DERM) to support landuse management to avoid/minimize blooms of Lyngbya in Moreton Bay, southeast Queensland, and other similar settings. A total of 38 boreholes were established in the mainland Pumicestone region and four sampling rounds of groundwater carried out in both dry and wet conditions. These groundwater samples were measured in the field for physico-chemical parameters, and in the laboratory analyses for the nutrients of concern, and other major and minor ions. Aquifer materials were confirmed using the Geological Survey of Queensland digital geology map, and geomaterials were assigned to seven categories which are A (sands), B (silts, sandy silts), C (estuarine mud, silts), D (humid soils), E (alluvium), F (sandstone) and G (other bedrock). The results of the water chemistry were examined by use of the software package AquaChem/AqQA, and divided into six groundwater groups, based on groundwater chemical types and location of boreholes. The type of aquifer material and location, and proximity to waterways was found to be important because they affected physico-chemical properties and concentrations of nutrients of concern and dissolved ions. The analytical results showed that iron concentrations of shallow groundwaters were high due to acid sulfate soils, and also mud and silt, but were lower in sand materials. DOC concentrations of these shallow groundwaters in the sand material were high probably due to rapid infiltration. In addition, DOC concentrations in some boreholes were high because they were installed in organic rich wetlands. The pH values of boreholes were from acidic to near neutral; some boreholes with pH values were low (< 4), showing acid sulfate soils in these boreholes. Concentrations of total nitrogen and total phosphorus of groundwaters were generally low, and the main causes of elevated concentrations of total nitrogen and total phosphorus are largely due to animal and human wastes and tend to be found in localized source areas. Comparison of the relative percentage of nitrogen species (NH3/NH4< Org-N, NO3-N and NO2-N) demonstrated that they could be related to sources such as animal waste, residential and agricultural fertilizers, forest and vegetation, mixed residents and farms, and variable setting and vegetation covers. Total concentrations of dissolved ions in sampling round 3 (dry period) were higher than those in sampling round 2 (wet period) due to both evaporation of groundwater in the dry period and the dilution of rainfall in the wet period. This showed that the highest concentrations of nutrients of concern were due to acid sulfate soils, aquifer materials, landuse and anthropogenic activities and were typically in aquifer materials of E (alluvium) and C (estuarine muds) and locations of Burpengary, Caboolture, and Glass Mountain catchments.

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29

Harbison, John E. "The occurrence and chemistry of groundwater on Bribie Island, a large barrier island in Moreton Bay, Southeast Queensland." Thesis, Queensland University of Technology, 1998.

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30

Leishman, Natalie. "Model Sensitivity, Performance and Evaluation Techniques for The Air Pollution Model in Southeast Queensland." Thesis, Queensland University of Technology, 2005. https://eprints.qut.edu.au/16148/1/Natalie_Leishman.pdf.

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One important component for successful air quality modelling is the utilisation of a reliable meteorological simulator. Evaluating the model with respect to its overall performance in predicting natural processes is no easy task. The problem is twofold, firstly there is the availability and suitability of field data with which to compare a model with and secondly there is the method of evaluation. The Air Pollution Model (TAPM), developed by the CSIRO was used to simulate the winds in Southeast Queensland (SEQ). The complex nature of the airshed makes it difficult to compare modelled data with observational data as the observational data may be influenced by local phenomena. Evaluation of the model through the use of standard statistics and monthly and seasonal statistics illustrated that overall the model predicted the annual average wind speeds and temperatures well. Through the use of synoptic clustering, more detail on model performance was gained and it was found that TAPM predicted sea breezes that occurred on high pollution days. The sensitivity of the model to the selection of input parameters such as soil type, land use, vegetation, and rain processes was also investigated.

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31

Leishman, Natalie. "Model Sensitivity, Performance and Evaluation Techniques for The Air Pollution Model in Southeast Queensland." Queensland University of Technology, 2005. http://eprints.qut.edu.au/16148/.

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Abstract:

One important component for successful air quality modelling is the utilisation of a reliable meteorological simulator. Evaluating the model with respect to its overall performance in predicting natural processes is no easy task. The problem is twofold, firstly there is the availability and suitability of field data with which to compare a model with and secondly there is the method of evaluation. The Air Pollution Model (TAPM), developed by the CSIRO was used to simulate the winds in Southeast Queensland (SEQ). The complex nature of the airshed makes it difficult to compare modelled data with observational data as the observational data may be influenced by local phenomena. Evaluation of the model through the use of standard statistics and monthly and seasonal statistics illustrated that overall the model predicted the annual average wind speeds and temperatures well. Through the use of synoptic clustering, more detail on model performance was gained and it was found that TAPM predicted sea breezes that occurred on high pollution days. The sensitivity of the model to the selection of input parameters such as soil type, land use, vegetation, and rain processes was also investigated.

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32

Hodgkinson, Jonathan. "Sedimentary evolution, hydrogeology and geochemistry of a back-barrier sand island : Toorbul, Southeast Queensland." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/16686/1/Jonathan_Hodgkinson_Thesis.pdf.

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Small back-barrier sand islands are poorly known in terms of hydrogeology and have been overlooked in more extensive studies of coastal groundwater systems that include larger barrier island complexes. This study employs a three-fold sequential approach to aquifer characterisation in a back-barrier sand island. A three-dimensional stratigraphic model forms the foundation framework, being derived from a multidisciplinary approach to sedimentary analysis and the construction of a depositional chronology. A conceptual hydrostratigraphic model is formulated based on the translation of sedimentary facies to hydrofacies, combined with density dependent flow calculations and tidal oscillation measurements. Groundwater hydrochemical data and mineral geochemistry are integrated with the resulting hydrogeological model to examine water-rock interaction and solute transport mechanisms. The study area is Toorbul Island, a small back-barrier sand mass of ~5 km2 with a maximum surface elevation of ~3.5 m AHD, located in the Pumicestone Passage of Southeast Queensland. The island hosts a dual aquifer system consisting of an unconfined island freshwater lens, underlain by a semi-confined palaeovalley-fill aquifer. Groundwater in the semi-confined aquifer is hyper-saline, carrying high concentrations of dissolved metals, with iron, in particular, ranging from 40 to < 200 mg l-1. This is of significant interest for both human health and environmental management, because iron is an important nutrient source for toxic algal bacteria such as Lyngbya majuscula. Conceptual modelling demonstrates that iron oxides and hydroxides are the main source of iron in the semi-confined aquifer, with a contribution from ferruginous chlorite dissolution. Aqueous manganese and a proportion of the aqueous iron are derived from the dissolution of manganoan ilmenite. Ferric iron minerals also contribute a significant proportion of dissolved iron in the deeper regions of the unconfined aquifer. Aqueous iron in the shallow unconfined groundwater is limited by iron sulphides, which also regulate acidity and indirectly limit dissolved aluminium concentrations. Groundwater redox state governed by seasonal climatic fluxes is the most significant control on iron-bearing mineral phase stability. Transport of dissolved metals to the surrounding estuary and the adjacent barrier island groundwater system is limited by the rate of ion diffusion across transition zone boundaries. The overall conclusions derived from this research show that back-barrier islands should be evaluated as discrete hydrogeological entities. The stratigraphic complexity that may be apparent within these island landforms should not be underestimated and the model domain should not necessarily be treated as a homogeneous system. This complexity is exemplified by the relationship between the upper and lower aquifers on Toorbul Island and the associated distribution of groundwater compositional heterogeneity. The complex stratigraphy within the sedimentary pile is derived from the presence of a sub-surface palaeovalley and the sedimentary response to changing sea-level over time. Considering the current widespread distribution of estuarine systems, complex hydrogeology as exhibited by Toobul Island, may be common in many small back-barrier island groundwater systems. The aquifer characteristics and their influence on solute transport and delivery can have significant ramifications for the exploitation of the adjacent coastal plain and barrier island aquifers. The potential influence on the latter is of particular concern due to the pressure imposed on potable groundwater supplies by increasing population densities in coastal areas.

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33

Hodgkinson, Jonathan. "Sedimentary evolution, hydrogeology and geochemistry of a back-barrier sand island : Toorbul, Southeast Queensland." Queensland University of Technology, 2008. http://eprints.qut.edu.au/16686/.

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Abstract:

Small back-barrier sand islands are poorly known in terms of hydrogeology and have been overlooked in more extensive studies of coastal groundwater systems that include larger barrier island complexes. This study employs a three-fold sequential approach to aquifer characterisation in a back-barrier sand island. A three-dimensional stratigraphic model forms the foundation framework, being derived from a multidisciplinary approach to sedimentary analysis and the construction of a depositional chronology. A conceptual hydrostratigraphic model is formulated based on the translation of sedimentary facies to hydrofacies, combined with density dependent flow calculations and tidal oscillation measurements. Groundwater hydrochemical data and mineral geochemistry are integrated with the resulting hydrogeological model to examine water-rock interaction and solute transport mechanisms. The study area is Toorbul Island, a small back-barrier sand mass of ~5 km2 with a maximum surface elevation of ~3.5 m AHD, located in the Pumicestone Passage of Southeast Queensland. The island hosts a dual aquifer system consisting of an unconfined island freshwater lens, underlain by a semi-confined palaeovalley-fill aquifer. Groundwater in the semi-confined aquifer is hyper-saline, carrying high concentrations of dissolved metals, with iron, in particular, ranging from 40 to < 200 mg l-1. This is of significant interest for both human health and environmental management, because iron is an important nutrient source for toxic algal bacteria such as Lyngbya majuscula. Conceptual modelling demonstrates that iron oxides and hydroxides are the main source of iron in the semi-confined aquifer, with a contribution from ferruginous chlorite dissolution. Aqueous manganese and a proportion of the aqueous iron are derived from the dissolution of manganoan ilmenite. Ferric iron minerals also contribute a significant proportion of dissolved iron in the deeper regions of the unconfined aquifer. Aqueous iron in the shallow unconfined groundwater is limited by iron sulphides, which also regulate acidity and indirectly limit dissolved aluminium concentrations. Groundwater redox state governed by seasonal climatic fluxes is the most significant control on iron-bearing mineral phase stability. Transport of dissolved metals to the surrounding estuary and the adjacent barrier island groundwater system is limited by the rate of ion diffusion across transition zone boundaries. The overall conclusions derived from this research show that back-barrier islands should be evaluated as discrete hydrogeological entities. The stratigraphic complexity that may be apparent within these island landforms should not be underestimated and the model domain should not necessarily be treated as a homogeneous system. This complexity is exemplified by the relationship between the upper and lower aquifers on Toorbul Island and the associated distribution of groundwater compositional heterogeneity. The complex stratigraphy within the sedimentary pile is derived from the presence of a sub-surface palaeovalley and the sedimentary response to changing sea-level over time. Considering the current widespread distribution of estuarine systems, complex hydrogeology as exhibited by Toobul Island, may be common in many small back-barrier island groundwater systems. The aquifer characteristics and their influence on solute transport and delivery can have significant ramifications for the exploitation of the adjacent coastal plain and barrier island aquifers. The potential influence on the latter is of particular concern due to the pressure imposed on potable groundwater supplies by increasing population densities in coastal areas.

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34

Tutua, Shane Sarere. "Residue Management and Carbon and Nutrient Cycling in Exotic Pine Plantations of Southeast Queensland." Thesis, Griffith University, 2009. http://hdl.handle.net/10072/366298.

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In Southeast Queensland, Australia, future wood production from exotic pines will rely heavily on second-rotation plantations. This increases the importance of sustaining soil fertility through logging or harvest residue retention for soil organic matter (SOM) maintenance in forest plantations. However, a greater understanding of harvest residues and their impact is essential to fully realise the potential of harvest residue management as an integral component of sustainable production forestry. Therefore, this study examined the nature of harvest residues, their decomposition and nutrient release dynamics, and the short- and long-term impacts of the residues on soil carbon (C), nitrogen (N) and phosphorous (P) pools, tree nutrition, growth and productivity in exotic pine plantations of Toolara State forest (26 degrees 00' South, 152 degrees 49' East), Maryborough districy, southeast Queensland.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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35

Spring, Ken. "Groundwater flow model for a large sand mass with heterogeneous media, Bribie island, southeast Queensland." Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16230/1/Ken_Spring_Thesis.pdf.

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On the large sand mass of Bribie Island, the sedimentary evolution related to sea level changes has resulted in marked spatial variations of aquifer properties. The main influence on groundwater behaviour is the induration of layers within the sandy sequences that comprise the island. The degree of induration controls vertical flows between the perched watertable and the underlying semi-confined regional aquifer. To identify heterogeneity within the indurated zone, an analysis of bore hydrographs was undertaken. The analysis shows that separate sections of the hydrological profile across the island display distinct unconfined or confined behaviour depending on the degree of hydrological discontinuity in the sandrock horizon. A two-dimensional (2-D) hydrogeologic conceptual model of Bribie Island is developed for the numerical modelling process. The two-aquifer system separated by the indurated layer ("coffee rock") is incorporated into the groundwater model. The indurated layer is spatially variable in thickness, continuity and permeability. An evaluation of the recharge and drainage parameters is conducted for improvement of model accuracy, using MODFLOW software to solve the quasi three-dimensional (3-D) flow model. The evapotranspiration (ET) parameter is tested due to the important role it has in the water balance of Bribie Island. The groundwater extraction and wastewater infiltration rates are evaluated separately for model input. Average hydraulic conductivities initially used in the numerical model for each aquifer do not match measured heads adequately. During initial model development, pilot point parameterisation of hydraulic conductivities was conducted providing a more complex distribution of the parameter and a better fit to observed water levels. Using spatial interpolation techniques, a gradual and realistic distribution of hydraulic properties is achieved rather than sharp changes between facies-related sedimentary sequences. The resultant visualisation of hydraulic conductivities supports the outcomes of the analysis of water level profiles. The model interprets and adjusts for the effects of the aquifer heterogeneity in respect to the hydraulic conductivity parameter. Areas of unconfined aquifer behaviour correspond to zones of higher hydraulic conductivities and are interpreted as regions of higher permeability due to a lesser degree of induration. Such zones of greater groundwater flow were found in the south of the island, the central swale and the northwest coastline, which act as connections to the basal aquifer enabling preferred recharge to it. Calibration is conducted in respect of the hydraulic conductivity, drainage and ET parameters. The calibration of simulated to observed hydraulic heads (objective function of 2.96 and correlation of 0.993) for the two layers achieved a close fit. The groundwater study demonstrates that both a statistical approach and numerical modelling are important in testing and refining the conceptual model. The modified conceptual model can be used as a basis for the construction of an improved and more reliable numerical model. The integration of geological information and spatial variability of aquifer parameters to produce a quasi three-dimensional model based on a two-aquifer conceptual model is a significant innovation of the modelling approach to Bribie Island. This approach contributes to a clearer understanding of the hydrogeological processes within the island. The investigation has contributed to a better understanding of the effects of broad and finer scale heterogeneities on groundwater dynamics in large sand mass.

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36

Spring, Ken. "Groundwater flow model for a large sand mass with heterogeneous media, Bribie island, southeast Queensland." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16230/.

Full text

Abstract:

On the large sand mass of Bribie Island, the sedimentary evolution related to sea level changes has resulted in marked spatial variations of aquifer properties. The main influence on groundwater behaviour is the induration of layers within the sandy sequences that comprise the island. The degree of induration controls vertical flows between the perched watertable and the underlying semi-confined regional aquifer. To identify heterogeneity within the indurated zone, an analysis of bore hydrographs was undertaken. The analysis shows that separate sections of the hydrological profile across the island display distinct unconfined or confined behaviour depending on the degree of hydrological discontinuity in the sandrock horizon. A two-dimensional (2-D) hydrogeologic conceptual model of Bribie Island is developed for the numerical modelling process. The two-aquifer system separated by the indurated layer ("coffee rock") is incorporated into the groundwater model. The indurated layer is spatially variable in thickness, continuity and permeability. An evaluation of the recharge and drainage parameters is conducted for improvement of model accuracy, using MODFLOW software to solve the quasi three-dimensional (3-D) flow model. The evapotranspiration (ET) parameter is tested due to the important role it has in the water balance of Bribie Island. The groundwater extraction and wastewater infiltration rates are evaluated separately for model input. Average hydraulic conductivities initially used in the numerical model for each aquifer do not match measured heads adequately. During initial model development, pilot point parameterisation of hydraulic conductivities was conducted providing a more complex distribution of the parameter and a better fit to observed water levels. Using spatial interpolation techniques, a gradual and realistic distribution of hydraulic properties is achieved rather than sharp changes between facies-related sedimentary sequences. The resultant visualisation of hydraulic conductivities supports the outcomes of the analysis of water level profiles. The model interprets and adjusts for the effects of the aquifer heterogeneity in respect to the hydraulic conductivity parameter. Areas of unconfined aquifer behaviour correspond to zones of higher hydraulic conductivities and are interpreted as regions of higher permeability due to a lesser degree of induration. Such zones of greater groundwater flow were found in the south of the island, the central swale and the northwest coastline, which act as connections to the basal aquifer enabling preferred recharge to it. Calibration is conducted in respect of the hydraulic conductivity, drainage and ET parameters. The calibration of simulated to observed hydraulic heads (objective function of 2.96 and correlation of 0.993) for the two layers achieved a close fit. The groundwater study demonstrates that both a statistical approach and numerical modelling are important in testing and refining the conceptual model. The modified conceptual model can be used as a basis for the construction of an improved and more reliable numerical model. The integration of geological information and spatial variability of aquifer parameters to produce a quasi three-dimensional model based on a two-aquifer conceptual model is a significant innovation of the modelling approach to Bribie Island. This approach contributes to a clearer understanding of the hydrogeological processes within the island. The investigation has contributed to a better understanding of the effects of broad and finer scale heterogeneities on groundwater dynamics in large sand mass.

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37

Haines, Heather. "The Application of Dendroclimatology to Reconstruct Long-Term Rainfall Records for Subtropical Southeast Queensland, Australia." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/371985.

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In the tropical and subtropical regions of eastern Australia multidecadal periods of floods and droughts have major economic and environmental consequences. Due to the short duration of instrumental rainfall records in this region the temporal pattern of these extreme events is poorly understood. Subtropical Southeast Queensland (SEQ) is one area that frequently experiences floods and droughts and is lacking in both instrumental rainfall records and sources of proxy data. There are old growth forest stands found in National Parks where dendroclimatology, the reconstruction of climate using tree-rings, can be applied. Tree rings have been widely utilized in temperate environments to provide annually-resolved centennial-scale climate information. However, in tropical and subtropical regions dendroclimatology has been underutilized, as many species in these regions are difficult to analyse. These species have short life-spans, poorly preserved timber, and are believed to exhibit numerous ring anomalies making dating of ring series difficult. Due to this, few species have been analysed for relationships between tree growth and climate. Recent reviews of both tropical and Australian dendrochronology have suggested that if a multi-technique approach is applied more species could be found suitable for use in reconstructing climate. This thesis first reviews the dendroclimatological history of Australia evaluating 36 studies across the continent that examined tree and shrub species for growth-climate relationships. This review showed that all four climate zones of Australia; temperate, arid, tropical, and subtropical, contained species that had the potential to provide high-quality, long-term climate reconstructions in areas under represented by instrumental data. Only four climate reconstructions have been developed in Australia. In all of these studies a combination of traditional ring-width measurements and modern analysis techniques allowed for the reconstructions to be developed. Several species located in SEQ had been assessed for growth-climate relationships and were found to grow as a result of rainfall conditions, with trees in the Araucariaceae family demonstrating the most potential. These trees are longer lived than most tropical/subtropical species, are known to put on annual rings, and grow as a result of environmental conditions which led them to be targeted in this thesis. Secondly, to test the spatial patterns of SEQ rainfall the instrumental data network was evaluated with Pearson correlation analysis undertaken on 140 rainfall stations active during 1908 to 2007. Stations are clustered into groups that correlate at r = 0.80, 0.85, and 0.90 levels. The pattern produced indicates that rainfall across SEQ is not uniform with correlated groups being separated by the Great Dividing Range with both coast-inland and north-south separations. To determine the effect this spatial variability has on the spatial applicability of rainfall reconstruction, the 140-year Toona ciliata tree-ring width record developed by Heinrich et al. (2009) is compared with the different rainfall groups and subgroups observed across SEQ. The rainfall reconstruction is found to best represent the spatial subgroups within which it is contained rather than representing the entire regional rainfall network. This suggests that several sites within SEQ need to be targeted to develop rainfall reconstructions for the region. Consequently three spatial distributed sites are targeted within SEQ with cores collected from Araucaria cunninghamii trees in D’Aguilar and Lamington National Parks and Araucaria bidwillii trees in Bunya Mountains National Park. These Araucariaceae cores are assessed for ring anomalies though the application of visual ring dating with false, faint, locally absent, and pinching rings found to be present in both species. However, through the use of bomb-pulse radiocarbon dating of A. cunninghamii samples anomalous rings are identified and annual growth patterns determined. Dendrometers are installed at the Lamington and Bunya Mountains sites to determine the exact growth-climate relationships for these species in SEQ. The amount of growth experienced by these trees is driven by annual rainfall while minimum temperatures are shown to be influencing the start and conclusion of the growth seasons. These results suggest that annual rainfall can be reconstructed from Araucariaceae trees when dating is verified using radiocarbon dating to account for ring anomalies. Two statistically significant rainfall reconstructions developed from A. cunninghamii trees are then presented. The first is a 69-year rainfall reconstruction for Brisbane developed from the D’Aguilar site. The trees at this location are all found to exhibit faint, indeterminate ring boundaries making them unsuitable for traditional visual ring-dating. A new method is presented using x-radiographs and density patterns scanned using an Itrax core scanner to build this reconstruction. Thirty-nine 12mm cores from twenty trees have their ring boundaries identified on the Itrax produced images based on features visible in the radiographs and the density patterns. Bombpulse radiocarbon dating is performed to verify the chronology. Climate response function analysis demonstrates that growth in driven by Austral annual (June-May) rainfall. The second reconstruction is a 164-year record developed from eighteen trees located in Lamington National Park. A field sampling strategy is applied where multiple cores are collected from the upslope, downslope, and across-slope sides of the study trees to help eliminate anomalous ring issues identified as being prevalent in these species. This chronology is then developed using traditional visual ring identification complemented by bomb-pulse radiocarbon dating to verify and correct the ring counts. Climate response function analysis indicates that Austral annual (June-May) rainfall is driving growth in these trees. Comparisons to both a Brisbane rainfall station (located about 100km from the Lamington site) and a station local to Lamington are undertaken with the rainfall signal at the local site more closely related to tree growth. Drought conditions are well represented by this chronology. The El Niño Southern Oscillation is found to be driving rainfall for the Lamington area but only since the 1940s.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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38

Virkki, Diana Angelique. "Faunal and Floral Community Responses to Contemporary Fire Regimes in Eucalypt Forests of Southeast Queensland." Thesis, Griffith University, 2014. http://hdl.handle.net/10072/367338.

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As an ecological process fire plays a global role in structuring ecosystems and their constituent fauna and flora. Fire is also regularly applied as a landscape management tool and altered fire regimes affect global biodiversity. Fire can have a marked influence on vegetation composition and structure with resultant flow on impacts on faunal communities. However, faunal responses to fire are often quite varied and management recommendations of appropriate fire regimes therefore generally include utilising a fire mosaic approach to fire management. This thesis investigates the relationship between variable fire regimes, vegetation composition, condition and structure, and ground-dwelling vertebrate faunal communities. The literature review (Chapter 1) revealed several gaps in current knowledge. This included a lack of detailed knowledge on the effects of variable fire regimes, including repeated management burns and fire mosaics, representative of multiple fire parameters (time since fire, number of fires, fire interval and fire type), on ecosystem biota. This was particularly evident for subtropical ecosystems. To analyse the effects of repeated burns, fire exclusion and wildfire, this study targeted one of the longest running fire experiments in Australia, at Bauple State Forest, where fire treatments have been applied annually since 1952 and triennially since 1973. Additional dry eucalypt forest sites at St Mary and Tiaro State Forests were included that represented variable fire management practices. Detailed fauna trapping surveys and vegetation assessments were completed on 35 plots across eight fire treatments at all three sites. Additionally, a broader scale GIS analysis of fire history was done across the three forests with surveys undertaken at an additional 74 sites allowing a comparison of reptile communities, forest condition and structure among variable fire regimes at multiple scales.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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39

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.

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40

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.

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41

Standage, Sarah. "Changing stories, Developing identities, Transforming education : A narrative, thematic study of cultural identity in refugee-inclusive English classrooms." Thesis, Griffith University, 2015. http://hdl.handle.net/10072/366093.

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This research project explores how English teachers can account for the cultural identities of refugee students and investigates how particular understandings of cultural identity can impact on teaching practice. At its centre, this project is interested in how teachers practise in socially just ways. In Australia and within its major social institutions, debate is continuous over the place and treatment of refugees, however, in terms of education, the schooling of refugee students has not been given enough serious and fine-grained consideration. The empirical study was concerned with how cultural identity was accounted for in the stories told by specific Queensland English teachers and students, and ultimately, how cultural identity mattered in the teaching of refugee-inclusive English classes. The research was conducted at a Southeast Queensland school because it had a high population of refugee students and teachers who were keen to deliberate on their own understandings of cultural identity.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Education and Professional Studies
Arts, Education and Law
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42

Kwik, Jeffrey T. B. "Soft sediment intertidal pools as a habitat for fish and prawns in Moreton Bay, Southeast Queensland /." St. Lucia, Qld, 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17437.pdf.

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43

Renwick, Juanita. "Population structure and genetic diversity of Southeast Queensland populations of the Wallum Froglet, Crinia Tinnula (Tschudi)." Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16181/1/Juanita_Renwick_Thesis.pdf.

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Abstract:

Genetic diversity is a fundamental attribute that contributes to a species evolutionary survival. In recent times, conservation managers have recognized the need to preserve genetic diversity of declining species, and have also acknowledged the utility of genetic markers for describing genetic and ecological relationships within and among populations. Information obtained from genetic studies can be used in conjunction with information on population demography, land use patterns and habitat distribution to develop effective management strategies for the conservation of species in decline. The wallum froglet, Crinia tinnula, is one of Australia's smallest habitat specialist anurans. In recent years there has been a dramatic decrease in population numbers of this species. The habitat to which C.tinnula is endemic ('wallum' habitat) is restricted to low coastal plains along the southeast Queensland and northern New South Wales coastline. As human populations in this region expanded, the coastal areas have undergone significant development and large areas of wallum habitat have been cleared. The effect has been to convert once largely continuous patches of coastal heathland in to a matrix of small habitat patches within an area undergoing rapid urban expansion. This study aimed to document levels and patterns of genetic diversity and to define the population structure of C.tinnula populations within southeast Queensland, with the objective of defining possible conservation management units for this species. Results from 12S and COI mitochondrial markers clearly showed that two distinct evolutionary lineages of C.tinnula are present within southeast Queensland. The high level of divergence between lineages and strict geographic partitioning suggests long term isolation of C.tinnula populations. It is hypothesized that ancestral C.tinnula populations were once confined to wallum habitat refugia during the Pliocene resulting in phylogeographic delineation of 'northern' and 'southern' C.tinnula clades. Populations within each geographic region show evidence of range contraction and expansion, with subsequent restricted gene flow. Levels of genetic diversity appear, largely, to be the product of historical associations rather than contemporary gene flow. A revision of the current systematics of C.tinnula is required to ensure that discrete population groups are recognized as distinct evolutionary lineages and will therefore be protected accordingly.

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44

Renwick, Juanita. "Population structure and genetic diversity of Southeast Queensland populations of the Wallum Froglet, Crinia Tinnula (Tschudi)." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16181/.

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Abstract:

Genetic diversity is a fundamental attribute that contributes to a species evolutionary survival. In recent times, conservation managers have recognized the need to preserve genetic diversity of declining species, and have also acknowledged the utility of genetic markers for describing genetic and ecological relationships within and among populations. Information obtained from genetic studies can be used in conjunction with information on population demography, land use patterns and habitat distribution to develop effective management strategies for the conservation of species in decline. The wallum froglet, Crinia tinnula, is one of Australia's smallest habitat specialist anurans. In recent years there has been a dramatic decrease in population numbers of this species. The habitat to which C.tinnula is endemic ('wallum' habitat) is restricted to low coastal plains along the southeast Queensland and northern New South Wales coastline. As human populations in this region expanded, the coastal areas have undergone significant development and large areas of wallum habitat have been cleared. The effect has been to convert once largely continuous patches of coastal heathland in to a matrix of small habitat patches within an area undergoing rapid urban expansion. This study aimed to document levels and patterns of genetic diversity and to define the population structure of C.tinnula populations within southeast Queensland, with the objective of defining possible conservation management units for this species. Results from 12S and COI mitochondrial markers clearly showed that two distinct evolutionary lineages of C.tinnula are present within southeast Queensland. The high level of divergence between lineages and strict geographic partitioning suggests long term isolation of C.tinnula populations. It is hypothesized that ancestral C.tinnula populations were once confined to wallum habitat refugia during the Pliocene resulting in phylogeographic delineation of 'northern' and 'southern' C.tinnula clades. Populations within each geographic region show evidence of range contraction and expansion, with subsequent restricted gene flow. Levels of genetic diversity appear, largely, to be the product of historical associations rather than contemporary gene flow. A revision of the current systematics of C.tinnula is required to ensure that discrete population groups are recognized as distinct evolutionary lineages and will therefore be protected accordingly.

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45

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.

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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.

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46

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.

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47

Millington, Heidi Kathryn. "Spatial Analysis of the Impacts of Urbanisation on the Health of Ephemeral Streams in Southeast Queensland." Thesis, Griffith University, 2016. http://hdl.handle.net/10072/367358.

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Abstract:

Aquatic ecosystems are vulnerable to threats from human activity. Numerous studies have shown that urban freshwater stream ecosystems are especially vulnerable to the intensity and complexity of stream health stressors associated with activities in the surrounding urban landscape. Scientists, government organisations and local volunteer groups are well aware of the deteriorating health of urban streams and are working towards understanding and managing the sources of stress on stream health. Improving the health of urban streams has the potential to provide local benefits such as biodiversity protection, enhanced ecosystem health, water purification, access to green space, scenic amenity and improved land values. While several important stressors have been identified in the Urban Stream Syndrome (elevated sediments, nutrients and contaminants, increased hydrologic flashiness and altered riparian and biotic assemblages) further research is required on the most important stressors and the mechanisms by which they impact stream health, especially in systems within dry climates where urban streams experience low flow conditions and flashy natural hydrology. Catchment-scale impervious surface has been identified in previous studies as a major driver of altered urban stream hydrology leading to degraded stream health. However, especially in drier climates, other aspects such as water quality and ecological processes associated with longitudinal and lateral connectivity have been identified as potentially more important stressors on urban stream health.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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48

Jiang, Qi. "Soil Carbon and Nitrogen Dynamics in the Riparian Zones of Wyaralong Dam in Southeast Queensland, Australia." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/368186.

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Riparian zones are considered to be dynamic boundaries between terrestrial and aquatic systems, and are of primary importance in maintaining the vitality of landscapes and of surface water bodies. As an important part of the ecosystem, riparian zones are important for ecosystem functions and services, including biodiversity, water quality and recreation. However, riparian areas are often profoundly modiﬁed and degraded, with signiﬁcant losses of ecological signiﬁcance and functioning. The construction of dam is well known to change the local ecological patterns, especially by reducing the magnitude and frequency and changing duration of flood events. Soil moisture plays a key role in determining the vitality and activity of soil microorganisms by controlling water and oxygen availability in the soils, therefore affecting microbial mediated carbon (C) and nitrogen (N) transformations in the riparian areas. Net accumulation of soil organic matter (SOM) in submerged soils often occur compared with those in the aerobic soils, due to the decrease in SOM decomposition. Nitrogen turnover in riparian soils is especially sensitive to soil moisture regimes. Autotrophic nitrification mainly occurs under aerobic conditions; while ammonification and immobilization of ammonium (NH4 ) could happen under both aerobic and anaerobic conditions. Soil N could be lost as nitrous oxide (N2O) through nitrification under aerobic conditions, and through denitrification under anaerobic conditions. Rewetting dry soil always leads to a pulse of respiration and perhaps N mineralisation.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Natural Sciences
Science, Environment, Engineering and Technology
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49

Rudorfer, Vivien Ellen. "Groundwater flow model of the Logan river alluvial aquifer system Josephville, South East Queensland." Thesis, Queensland University of Technology, 2009. https://eprints.qut.edu.au/29322/1/Vivien_Rudorfer_Thesis.pdf.

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Abstract:

The study focuses on an alluvial plain situated within a large meander of the Logan River at Josephville near Beaudesert which supports a factory that processes gelatine. The plant draws water from on site bores, as well as the Logan River, for its production processes and produces approximately 1.5 ML per day (Douglas Partners, 2004) of waste water containing high levels of dissolved ions. At present a series of treatment ponds are used to aerate the waste water reducing the level of organic matter; the water is then used to irrigate grazing land around the site. Within the study the hydrogeology is investigated, a conceptual groundwater model is produced and a numerical groundwater flow model is developed from this. On the site are several bores that access groundwater, plus a network of monitoring bores. Assessment of drilling logs shows the area is formed from a mixture of poorly sorted Quaternary alluvial sediments with a laterally continuous aquifer comprised of coarse sands and fine gravels that is in contact with the river. This aquifer occurs at a depth of between 11 and 15 metres and is overlain by a heterogeneous mixture of silts, sands and clays. The study investigates the degree of interaction between the river and the groundwater within the fluvially derived sediments for reasons of both environmental monitoring and sustainability of the potential local groundwater resource. A conceptual hydrogeological model of the site proposes two hydrostratigraphic units, a basal aquifer of coarse-grained materials overlain by a thick semi-confining unit of finer materials. From this, a two-layer groundwater flow model and hydraulic conductivity distribution was developed based on bore monitoring and rainfall data using MODFLOW (McDonald and Harbaugh, 1988) and PEST (Doherty, 2004) based on GMS 6.5 software (EMSI, 2008). A second model was also considered with the alluvium represented as a single hydrogeological unit. Both models were calibrated to steady state conditions and sensitivity analyses of the parameters has demonstrated that both models are very stable for changes in the range of ± 10% for all parameters and still reasonably stable for changes up to ± 20% with RMS errors in the model always less that 10%. The preferred two-layer model was found to give the more realistic representation of the site, where water level variations and the numerical modeling showed that the basal layer of coarse sands and fine gravels is hydraulically connected to the river and the upper layer comprising a poorly sorted mixture of silt-rich clays and sands of very low permeability limits infiltration from the surface to the lower layer. The paucity of historical data has limited the numerical modelling to a steady state one based on groundwater levels during a drought period and forecasts for varying hydrological conditions (e.g. short term as well as prolonged dry and wet conditions) cannot reasonably be made from such a model. If future modelling is to be undertaken it is necessary to establish a regular program of groundwater monitoring and maintain a long term database of water levels to enable a transient model to be developed at a later stage. This will require a valid monitoring network to be designed with additional bores required for adequate coverage of the hydrogeological conditions at the Josephville site. Further investigations would also be enhanced by undertaking pump testing to investigate hydrogeological properties in the aquifer.

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50

Rudorfer, Vivien Ellen. "Groundwater flow model of the Logan river alluvial aquifer system Josephville, South East Queensland." Queensland University of Technology, 2009. http://eprints.qut.edu.au/29322/.

Full text

Abstract:

The study focuses on an alluvial plain situated within a large meander of the Logan River at Josephville near Beaudesert which supports a factory that processes gelatine. The plant draws water from on site bores, as well as the Logan River, for its production processes and produces approximately 1.5 ML per day (Douglas Partners, 2004) of waste water containing high levels of dissolved ions. At present a series of treatment ponds are used to aerate the waste water reducing the level of organic matter; the water is then used to irrigate grazing land around the site. Within the study the hydrogeology is investigated, a conceptual groundwater model is produced and a numerical groundwater flow model is developed from this. On the site are several bores that access groundwater, plus a network of monitoring bores. Assessment of drilling logs shows the area is formed from a mixture of poorly sorted Quaternary alluvial sediments with a laterally continuous aquifer comprised of coarse sands and fine gravels that is in contact with the river. This aquifer occurs at a depth of between 11 and 15 metres and is overlain by a heterogeneous mixture of silts, sands and clays. The study investigates the degree of interaction between the river and the groundwater within the fluvially derived sediments for reasons of both environmental monitoring and sustainability of the potential local groundwater resource. A conceptual hydrogeological model of the site proposes two hydrostratigraphic units, a basal aquifer of coarse-grained materials overlain by a thick semi-confining unit of finer materials. From this, a two-layer groundwater flow model and hydraulic conductivity distribution was developed based on bore monitoring and rainfall data using MODFLOW (McDonald and Harbaugh, 1988) and PEST (Doherty, 2004) based on GMS 6.5 software (EMSI, 2008). A second model was also considered with the alluvium represented as a single hydrogeological unit. Both models were calibrated to steady state conditions and sensitivity analyses of the parameters has demonstrated that both models are very stable for changes in the range of ± 10% for all parameters and still reasonably stable for changes up to ± 20% with RMS errors in the model always less that 10%. The preferred two-layer model was found to give the more realistic representation of the site, where water level variations and the numerical modeling showed that the basal layer of coarse sands and fine gravels is hydraulically connected to the river and the upper layer comprising a poorly sorted mixture of silt-rich clays and sands of very low permeability limits infiltration from the surface to the lower layer. The paucity of historical data has limited the numerical modelling to a steady state one based on groundwater levels during a drought period and forecasts for varying hydrological conditions (e.g. short term as well as prolonged dry and wet conditions) cannot reasonably be made from such a model. If future modelling is to be undertaken it is necessary to establish a regular program of groundwater monitoring and maintain a long term database of water levels to enable a transient model to be developed at a later stage. This will require a valid monitoring network to be designed with additional bores required for adequate coverage of the hydrogeological conditions at the Josephville site. Further investigations would also be enhanced by undertaking pump testing to investigate hydrogeological properties in the aquifer.

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