Tesi: "Vegetation (S.E.Australia)"

1

Roderick, Michael L. "Satellite derived vegetation indices for monitoring seasonal vegetation conditions in Western Australia". Thesis, Curtin University, 1994. http://hdl.handle.net/20.500.11937/518.

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Abstract (sommario):

The monitoring of continental and global scale net primary production remains a major focus of satellite-based remote sensing. Potential benefits which follow are diverse and include contributions to, and improved scientific understanding of, ecological systems, rangeland management, famine warning, agricultural commodity trading, and the study of global climate change.A NOAA-AVHRR data set containing monthly observations of green vegetation cover over a ten year period was acquired and analysed, to extract information on seasonal conditions. The data were supplied as a vegetation index, commonly known as the Normalised Difference Vegetation Index (NDVI), with a spatial resolution of approximately five km. The data set was acquired from three different satellites, and calibration problems were known to exist. A new technique was developed to estimate, and subsequently remove, the calibration bias present in the data.Monthly rainfall measurements were used as surrogate ground truth to validate the NDVI data. For regions of native vegetation, linear models relating NDVI to previous rainfall were derived, using transfer function techniques in common use in systems engineering. The models demonstrate that, in mid-latitude regions, the NDVI is a linear function of rainfall recorded over the preceding seven or eight months.Annual summaries of the image data were developed to highlight the amount and timing of plant growth. Three fundamental questions were posed as an aid to the development of the summary technique: where, when and how much? These summaries highlight the extraordinary spatial and temporal variations in plant growth, and hence rainfall, over much of Western Australia each year.Standard analysis techniques used in time series analysis, such as classical decomposition, were successfully applied to the analysis of NDVI time series. These techniques highlighted structural differences in the image data, due to land use, climatic factors and vegetation type.Overall, the results of the research undertaken in this study, using NOAA-AVHRR data in Western Australia, demonstrate that vegetation indices acquired from satellite platforms can be used to monitor continental scale seasonal conditions in an effective manner. As a consequence of these results, further research using this type of data is proposed in rangeland management and climate change modelling.

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2

Roderick, Michael L. "Satellite derived vegetation indices for monitoring seasonal vegetation conditions in Western Australia". Curtin University of Technology, School of Surveying and Land Information, 1994. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=14815.

Testo completo

Abstract (sommario):

The monitoring of continental and global scale net primary production remains a major focus of satellite-based remote sensing. Potential benefits which follow are diverse and include contributions to, and improved scientific understanding of, ecological systems, rangeland management, famine warning, agricultural commodity trading, and the study of global climate change.A NOAA-AVHRR data set containing monthly observations of green vegetation cover over a ten year period was acquired and analysed, to extract information on seasonal conditions. The data were supplied as a vegetation index, commonly known as the Normalised Difference Vegetation Index (NDVI), with a spatial resolution of approximately five km. The data set was acquired from three different satellites, and calibration problems were known to exist. A new technique was developed to estimate, and subsequently remove, the calibration bias present in the data.Monthly rainfall measurements were used as surrogate ground truth to validate the NDVI data. For regions of native vegetation, linear models relating NDVI to previous rainfall were derived, using transfer function techniques in common use in systems engineering. The models demonstrate that, in mid-latitude regions, the NDVI is a linear function of rainfall recorded over the preceding seven or eight months.Annual summaries of the image data were developed to highlight the amount and timing of plant growth. Three fundamental questions were posed as an aid to the development of the summary technique: where, when and how much? These summaries highlight the extraordinary spatial and temporal variations in plant growth, and hence rainfall, over much of Western Australia each year.Standard analysis techniques used in time series analysis, such as classical decomposition, were successfully applied to the analysis of NDVI time series. These techniques highlighted ++
structural differences in the image data, due to land use, climatic factors and vegetation type.Overall, the results of the research undertaken in this study, using NOAA-AVHRR data in Western Australia, demonstrate that vegetation indices acquired from satellite platforms can be used to monitor continental scale seasonal conditions in an effective manner. As a consequence of these results, further research using this type of data is proposed in rangeland management and climate change modelling.

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3

Scherrer, Pascal, e n/a. "Monitoring Vegetation Change in the Kosciuszko Alpine Zone, Australia". Griffith University. Australian School of Environmental Studies, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040715.125310.

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Abstract (sommario):

This thesis examined vegetation change over the last 43 years in Australia's largest contiguous alpine area, the Kosciuszko alpine zone in south-eastern Australia. Using historical and current data about the state of the most common vegetation community, tall alpine herbfield, this thesis addressed the questions: (1) what were the patterns of change at the species/genera and life form levels during this time period; (2) what were the patterns of recovery, if recovery occurred, from anthropogenic disturbances such as livestock grazing or trampling by tourists; (3) what impacts did natural disturbances such as drought have on the vegetation and how does it compare to anthropogenic disturbances; and (4) What are the benefits, limitations and management considerations when using long-term data for assessing vegetation changes at the species/genera, life form and community levels? The Kosciuszko alpine zone has important economic, cultural and ecological values. It is of great scientific and biological importance, maintaining an assemblage of vegetation communities found nowhere else in the world. It is one of the few alpine regions in the world with deep loamy soils, and contains endemic flora and fauna and some of the few periglacial and glacial features in Australia. The area also forms the core of the Australian mainland's most important water catchment and is a popular tourist destination, offering a range of recreational opportunities. The vegetation of the Kosciuszko alpine zone is recovering from impacts of livestock grazing and is increasingly exposed to pressures from tourism and anthropogenic climate change. At the same time, natural disturbances such as drought and fire can influence the distribution, composition and diversity of plants. Thus, there is a need for detailed environmental data on this area in order to: (1) better understand ecological relationships; (2) understand existing and potential effects of recreational and management pressures on the region; (3) provide data against which future changes can be assessed; and (4) provide better information on many features of this area, including vegetation, for interpretation, education and management. The research in this thesis utilised three types of ecological information: (1) scientific long-term datasets; (2) photographic records; and (3) a comparison of disturbed and undisturbed vegetation. This research analysed data from one of the longest ongoing monitoring programs in the Australian Alps established by Alec Costin and Dane Wimbush in 1959. Permanent plots (6 transects and 30 photoquadrats) were established at two locations that differed in the time since grazing and have been repeatedly surveyed. Plots near Mt Kosciuszko had not been grazed for 15 years and had nearly complete vegetation cover in 1959, while plots near Mt Gungartan showed extensive impacts of grazing and associated activities which only ceased in 1958. Some transect data from 1959 to 1978 have been analysed by the original researchers. The research presented in this thesis extends this monitoring program with data from additional surveys in 1990, 1999 and 2002 and applies current methods of statistical evaluation, such as ordination techniques, to the whole data set for the first time. Results indicated that the recovery from livestock grazing and the effects of drought have been the main factors affecting vegetation. Recovery from livestock grazing at the three transects at Gungartan was slow and involved: (1) increasing genera diversity; (2) increasing vegetation cover; (3) decreasing amounts of bare ground; and (4) a directional change over time in species composition. Patterns of colonisation and species succession were also documented. In 2002, 44 years after the cessation of grazing, transects near Mt Gungartan had similar vegetation cover and genera diversity to the transects near Mt Kosciuszko, but cover by exposed rock remained higher. A drought in the 1960s resulted in a temporary increase of litter and a shift in the proportional cover of life forms, as grasses died and herb cover increased at both locations. Proportions of cover for life forms reverted to pre-drought levels within a few years. The results also highlighted the spatial variability of tall alpine herbfield. The photoquadrats were surveyed in the years 1959, 1964, 1968, 1978 and 2001 and are analysed for the first time in this thesis. After comparing a range of methods, visual assessment using a 130 point grid was found to be the most suitable technique to measure vegetation cover and genera diversity. At the 18 quadrats near Mt Gungartan, there was a pattern of increasing vegetation cover as bare areas were colonised by native cudweeds and the naturalized herb Acetosella vulgaris. Revegetation from within bare areas largely occurred by herb species, while graminoids and shrub species predominately colonised bare ground by lateral expansion from the edges, eventually replacing the colonising herbs. At the 12 quadrats near Mt Kosciuszko, vegetation cover was almost complete in all years surveyed except 1968, which was at the end of a six year drought. Similar to the results from the transect study, the drought caused an increase in litter at both locations as graminoid cover declined. Initially herb cover increased, potentially as a result of decreased competition from the graminoids and a nutrient spike from decaying litter, but as the drought became more severe, herb cover also declined. Graminoid cover rapidly recovered after the drought, reaching pre-drought levels by 1978, and was at similar levels in 2001. Herb cover continued to decline after peaking in 1964. The photoquadrat study also documented the longevity and growth rates of several species indicating that many taxa may persist for several decades. It further provided insights into replacement patterns amongst life forms. In addition to assessing vegetation change following livestock grazing and drought at the long-term plots, recovery from tourism impacts was examined by comparing vegetation and soils on a closed walking track, with that of adjacent undisturbed tall alpine herbfield at a series of 22 paired quadrats. Fifteen years after the track was closed there was limited success in restoration. Over a quarter of the closed track was still bare ground with non-native species the dominant vegetation. Plant species composition differed and vegetation height, soil nutrients and soil moisture were lower on the track which had a higher compaction level than adjacent natural vegetation. The results presented in this thesis highlight that tall alpine herbfield is characterised by nearly entire vegetation cover which is dominated by graminoids, followed by herbs and shrubs in the absence of disturbance by livestock grazing, trampling or drought. The studies also showed that under quot;average" conditions, the relative cover of herbs and graminoids remained fairly stable even though there can be considerable cycling between them. Spatial variability in terms of taxa composition was high. The only common introduced species in unrehabilitated sites was Acetosella vulgaris, which was effective at colonising bare ground but was eventually replaced by other native species. However, in areas actively rehabilitated, such as on the closed track, non-native species introduced during revegetation efforts still persist with high cover 15 years after their introduction. Monitoring of vegetation change is also important at the landscape scale. This thesis provides a review of the potential use, the limitations and the benefits of aerial photography to examine vegetation change in the Kosciuszko alpine zone. Numerous aerial photography runs have been flown over the area since the 1930s for government agencies, industry and the military. Some of these records have been used to map vegetation communities and eroding areas at a point in time. Other studies compared different types and scales of photographs, highlighting in particular the benefits and potential of large scale colour aerial photography to map alpine vegetation. However, despite their potential to assess vegetation change over time, a temporal comparison of vegetation in the Kosciuszko alpine zone from aerial photographs has not been completed to this date. Historical photographs may not be easy to locate or access and difficulties with vegetation classification may restrict the practicality of using historical aerial photographs to assess vegetation change. Despite these issues, aerial photography may provide a very useful and efficient tool to assess changes over time when applied appropriately, even in alpine environments. The development of digital classification techniques, the application of statistical measures of error to both methodology and data, and the application of geographic information systems are likely to further improve the practicality of historical aerial photographs for the detection of vegetation change and assist in overcoming some of the limitations. The results presented in this thesis highlight the need for limiting disturbance, for ongoing rehabilitation of disturbed areas and for long-term monitoring in the Kosciuszko alpine zone. The results contribute to our understanding of how vegetation may change in the future and may be affected by new land use activities and climate change. This type of information, which otherwise would require the establishment of long-term studies and years of monitoring, can assist land managers of this and other important protected areas. The study highlights how the use and expansion of already existing datasets to gather ecological information can save considerable money and time, providing valuable data for current and emerging issues.

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4

Scherrer, Pascal. "Monitoring Vegetation Change in the Kosciuszko Alpine Zone, Australia". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/366283.

Testo completo

Abstract (sommario):

This thesis examined vegetation change over the last 43 years in Australia's largest contiguous alpine area, the Kosciuszko alpine zone in south-eastern Australia. Using historical and current data about the state of the most common vegetation community, tall alpine herbfield, this thesis addressed the questions: (1) what were the patterns of change at the species/genera and life form levels during this time period; (2) what were the patterns of recovery, if recovery occurred, from anthropogenic disturbances such as livestock grazing or trampling by tourists; (3) what impacts did natural disturbances such as drought have on the vegetation and how does it compare to anthropogenic disturbances; and (4) What are the benefits, limitations and management considerations when using long-term data for assessing vegetation changes at the species/genera, life form and community levels? The Kosciuszko alpine zone has important economic, cultural and ecological values. It is of great scientific and biological importance, maintaining an assemblage of vegetation communities found nowhere else in the world. It is one of the few alpine regions in the world with deep loamy soils, and contains endemic flora and fauna and some of the few periglacial and glacial features in Australia. The area also forms the core of the Australian mainland's most important water catchment and is a popular tourist destination, offering a range of recreational opportunities. The vegetation of the Kosciuszko alpine zone is recovering from impacts of livestock grazing and is increasingly exposed to pressures from tourism and anthropogenic climate change. At the same time, natural disturbances such as drought and fire can influence the distribution, composition and diversity of plants. Thus, there is a need for detailed environmental data on this area in order to: (1) better understand ecological relationships; (2) understand existing and potential effects of recreational and management pressures on the region; (3) provide data against which future changes can be assessed; and (4) provide better information on many features of this area, including vegetation, for interpretation, education and management. The research in this thesis utilised three types of ecological information: (1) scientific long-term datasets; (2) photographic records; and (3) a comparison of disturbed and undisturbed vegetation. This research analysed data from one of the longest ongoing monitoring programs in the Australian Alps established by Alec Costin and Dane Wimbush in 1959. Permanent plots (6 transects and 30 photoquadrats) were established at two locations that differed in the time since grazing and have been repeatedly surveyed. Plots near Mt Kosciuszko had not been grazed for 15 years and had nearly complete vegetation cover in 1959, while plots near Mt Gungartan showed extensive impacts of grazing and associated activities which only ceased in 1958. Some transect data from 1959 to 1978 have been analysed by the original researchers. The research presented in this thesis extends this monitoring program with data from additional surveys in 1990, 1999 and 2002 and applies current methods of statistical evaluation, such as ordination techniques, to the whole data set for the first time. Results indicated that the recovery from livestock grazing and the effects of drought have been the main factors affecting vegetation. Recovery from livestock grazing at the three transects at Gungartan was slow and involved: (1) increasing genera diversity; (2) increasing vegetation cover; (3) decreasing amounts of bare ground; and (4) a directional change over time in species composition. Patterns of colonisation and species succession were also documented. In 2002, 44 years after the cessation of grazing, transects near Mt Gungartan had similar vegetation cover and genera diversity to the transects near Mt Kosciuszko, but cover by exposed rock remained higher. A drought in the 1960s resulted in a temporary increase of litter and a shift in the proportional cover of life forms, as grasses died and herb cover increased at both locations. Proportions of cover for life forms reverted to pre-drought levels within a few years. The results also highlighted the spatial variability of tall alpine herbfield. The photoquadrats were surveyed in the years 1959, 1964, 1968, 1978 and 2001 and are analysed for the first time in this thesis. After comparing a range of methods, visual assessment using a 130 point grid was found to be the most suitable technique to measure vegetation cover and genera diversity. At the 18 quadrats near Mt Gungartan, there was a pattern of increasing vegetation cover as bare areas were colonised by native cudweeds and the naturalized herb Acetosella vulgaris. Revegetation from within bare areas largely occurred by herb species, while graminoids and shrub species predominately colonised bare ground by lateral expansion from the edges, eventually replacing the colonising herbs. At the 12 quadrats near Mt Kosciuszko, vegetation cover was almost complete in all years surveyed except 1968, which was at the end of a six year drought. Similar to the results from the transect study, the drought caused an increase in litter at both locations as graminoid cover declined. Initially herb cover increased, potentially as a result of decreased competition from the graminoids and a nutrient spike from decaying litter, but as the drought became more severe, herb cover also declined. Graminoid cover rapidly recovered after the drought, reaching pre-drought levels by 1978, and was at similar levels in 2001. Herb cover continued to decline after peaking in 1964. The photoquadrat study also documented the longevity and growth rates of several species indicating that many taxa may persist for several decades. It further provided insights into replacement patterns amongst life forms. In addition to assessing vegetation change following livestock grazing and drought at the long-term plots, recovery from tourism impacts was examined by comparing vegetation and soils on a closed walking track, with that of adjacent undisturbed tall alpine herbfield at a series of 22 paired quadrats. Fifteen years after the track was closed there was limited success in restoration. Over a quarter of the closed track was still bare ground with non-native species the dominant vegetation. Plant species composition differed and vegetation height, soil nutrients and soil moisture were lower on the track which had a higher compaction level than adjacent natural vegetation. The results presented in this thesis highlight that tall alpine herbfield is characterised by nearly entire vegetation cover which is dominated by graminoids, followed by herbs and shrubs in the absence of disturbance by livestock grazing, trampling or drought. The studies also showed that under quot;average" conditions, the relative cover of herbs and graminoids remained fairly stable even though there can be considerable cycling between them. Spatial variability in terms of taxa composition was high. The only common introduced species in unrehabilitated sites was Acetosella vulgaris, which was effective at colonising bare ground but was eventually replaced by other native species. However, in areas actively rehabilitated, such as on the closed track, non-native species introduced during revegetation efforts still persist with high cover 15 years after their introduction. Monitoring of vegetation change is also important at the landscape scale. This thesis provides a review of the potential use, the limitations and the benefits of aerial photography to examine vegetation change in the Kosciuszko alpine zone. Numerous aerial photography runs have been flown over the area since the 1930s for government agencies, industry and the military. Some of these records have been used to map vegetation communities and eroding areas at a point in time. Other studies compared different types and scales of photographs, highlighting in particular the benefits and potential of large scale colour aerial photography to map alpine vegetation. However, despite their potential to assess vegetation change over time, a temporal comparison of vegetation in the Kosciuszko alpine zone from aerial photographs has not been completed to this date. Historical photographs may not be easy to locate or access and difficulties with vegetation classification may restrict the practicality of using historical aerial photographs to assess vegetation change. Despite these issues, aerial photography may provide a very useful and efficient tool to assess changes over time when applied appropriately, even in alpine environments. The development of digital classification techniques, the application of statistical measures of error to both methodology and data, and the application of geographic information systems are likely to further improve the practicality of historical aerial photographs for the detection of vegetation change and assist in overcoming some of the limitations. The results presented in this thesis highlight the need for limiting disturbance, for ongoing rehabilitation of disturbed areas and for long-term monitoring in the Kosciuszko alpine zone. The results contribute to our understanding of how vegetation may change in the future and may be affected by new land use activities and climate change. This type of information, which otherwise would require the establishment of long-term studies and years of monitoring, can assist land managers of this and other important protected areas. The study highlights how the use and expansion of already existing datasets to gather ecological information can save considerable money and time, providing valuable data for current and emerging issues.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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5

Sadler, Rohan. "Image-based modelling of pattern dynamics in a semiarid grassland of the Pilbara, Australia /". Connect to this title, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0155.

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6

Tiver, Fleur. "The vegetation patterns of north-western Eyre Peninsula, South Australia /". Title page, contents and summary only, 1987. http://web4.library.adelaide.edu.au/theses/09S.B/09s.bt623.pdf.

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7

Sparrow, Ashley. "A geobotanical study of the remnant natural vegetation of temperate South Australia". Title page, contents and summary only, 1991. http://web4.library.adelaide.edu.au/theses/09PH/09phs7368.pdf.

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8

Brownlow, Marcus D. "Water regime and the aquatic vegetation of Bool Lagoon, South Australia /". Title page, table of contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phb8852.pdf.

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9

Webb, Ashley Adrian. "Episodic erosion, riparian vegetation colonisation and the late holocene stability of sand-bed, forest streams in southeastern Australia". Thesis, The University of Sydney, 2002. https://hdl.handle.net/2123/28458.

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Abstract (sommario):

Natural interactions between riparian vegetation, large woody debris (LWD) and the fluvial geomorphology of forest streams in North America and Europe have been well researched. In southeastern Australia, where rainfall and runoff are highly variable, where riparian vegetation species are unique and where many streams have been altered since European settlement, there is a paucity of research on such biogeomorphic interactions. This thesis aimed to partly address this knowledge gap by undertaking detailed case studies of four undisturbed streams that varied in their degree of lateral confinement by materials of limited erodibility, i.e. differences in the size and nature of the valley floor trough. These included a laterally and vertically bedrock-confined channel flanked by a series of discontinuous inchannel benches but with no floodplain (Mogo Creek); a laterally bedrock-confined channel flanked by a discontinuous high vertically accreted floodplain and a series of discontinuous in-channel benches (Wheeny Creek); a partially bedrock- and terrace-confined channel discontinuously flanked by pockets of floodplain (Bruces Creek); and a slightly terraceconfined channel continuously flanked by floodplain (Tonghi Creek). Extensive radiocarbon dating of floodplain charcoal at each site highlighted the fact that episodic, rainfall-generated cataclysmic floods have occurred during the late Holocene. These floods totally removed alluvial landforms, including the floodplain forest, from within the valley floor trough. Riparian vegetation communities that have colonised the landforms that redeveloped in the erosional void exhibit a distinct lateral and vertical zonation of species that is determined by the degree of resistance of different species to natural flood disturbance. More flood-resistant tree species, such as Tristaniopsis laurina, are able to grow and survive within the channel and on the channel banks and in—channel benches; possess the ability to reshoot from epicormic buds following high-energy flood disturbance; and can rapidly colonise recently formed alluvial landforms. Less flood—resistant species, such as the Eucalyptus species, grow on higher parts of the floodplain or on remnant Pleistocene river terraces where flood flows are of lower energy and occur less frequently. Measured LWD loadings ranged from 47 m3ha‘I at Mogo Creek to 751 m3ha‘l at Bruces Creek and varied in relation to specific stream power, the relaxation period between cataclysmic floods and the age-structure of the riparian vegetation community from which the LWD was recruited. Large woody debris recruitment processes varied in relation to the geomorphic setting and zonation of riparian vegetation. Episodic bank erosion, undercutting and senescence were identified as the dominant LWD recruitment processes from T. laurina trees growing along the banks of Tonghi and Bruces Creeks, while episodic windthrow was identified as the LWD recruitment process from Eucalyptus trees growing on the floodplains and terraces at these sites. At Mogo and Wheeny Creeks, destruction of in—channel benches by catastrophic floods was identified as the dominant LWD recruitment process from T. laurina and Leptospermum polygalifolium shrubs, while episodic windthrow was the dominant LWD recruitment process from the Eucalyptus trees growing on the high floodplains, where present, and adjacent hillslopes. The longitudinal distribution, orientation and hydraulic impacts of LWD pieces, and the development of log-steps were strongly influenced by the energy of flows experienced and the ratio of tree and LWD size to channel size. Due to high timber densities LWD tends to sink and become partially or completely buried by bedload. It is only in streams with high LWD loadings, low to medium energy bankfull flows and high LWD size to channel size ratios, such as Bruces Creek, that interlocking, wedged pieces of LWD form closely spaced debris dams. The maximum residence time for LWD identified by radiocarbon dating was 980 years on Eucalyptus timber in Wheeny Creek and was interpreted as representing the relaxation period following the most recent cataclysmic flood. Biogeomorphic evidence indicates that riparian vegetation and large woody debris can exert a significant influence on the fluvial geomorphology of sand-bed, forest streams in southeastern Australia by contributing to processes such as pool formation, stream energy dissipation, bank strength, sediment storage patterns, bed stability, oblique bank accretion, in—channel bench and mid-channel bar formation. However, rainfall—generated cataclysmic floods, capable of totally obliterating all landforms within the valley floor trough, including the floodplain forest, have occurred during the late Holocene. Cataclysmic floods exceed vegetationcontrolled thresholds of channel and floodplain stability and resultant specific stream powers of at least 2500 Wm‘2 enable the flood to erode the channel and floodplain to bedrock. Such floods occur more frequently in flood variable regions on high energy streams in narrow valley floor troughs. The width and nature of the valley floor trough, specific stream power and the relaxation period between floods are identified as important factors determining the subsequent influence of riparian vegetation and LWD on the stability of the landforms that redevelop in the erosional void.

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10

Hawke, Bruce. "Vegetation analysis with biogeographic implications in North-East Eyre Peninsula, South Australia /". Title page, summary and contents only, 1986. http://web4.library.adelaide.edu.au/theses/09SB/09sbh392.pdf.

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11

Tiver, Fleur. "Vegetation patterns of eastern South Australia : edaphic control and effects of herbivory /". Title page, contents and abstract only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09pht623.pdf.

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12

Bickford, Sophia Anastasia. "A historical perspective on recent landscape transformation: integrating palaeoecological, documentary and contemporary evidence for former vegetation patterns and dynamics in the Fleurieu Peninsula, South Australia". Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phb583.pdf.

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Abstract (sommario):

Includes bibliographical references (p. 301-319). Palaeoecological records, documented historical records and remnant vegetation were investigated in order to construct a multi-scaled history of vegetation pattern and change in the Fleurieu Peninsula, South Australia over the last c. 8000 years. Aims to better understand post-European landscape transformation and address the inherently historical components of the problems of regional biodiversity loss, land sustainability and the cumulative contribution to global climatic change.

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13

Krisjansen, Ivan A. "A genealogy of unemployment : press representations in South Australia 1890's and 1930's /". Title page, table of contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phk9262.pdf.

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14

Capon, Samantha Jane, e n/a. "Flow Variability and Vegetation Dynamics in a Large Arid Floodplain: Cooper Creek, Australia". Griffith University. Australian School of Environmental Studies, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040513.110733.

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Abstract (sommario):

Throughout arid and semi-arid inland Australia, many extensive floodplains occur in association with rivers which are amongst the most hydrologically variable in the world. As rainfall in these areas is characteristically low and patchy, conditions in Australia's 'dryland' floodplains fluctuate unpredictably between extended periods of drought and huge floods that transform vast areas into wetlands, often for months at a time. Vegetation in these floodplains is commonly dominated by short grass and forb associations and patches of open succulent shrubland which are attributed with high ecological and socio-economic values due to their provision of habitat to a diverse array of terrestrial and aquatic fauna and their productive native pasture growth. In temperate and tropical floodplains, a substantial number of studies have shown that plant community composition and structure is determined primarily by flow and alterations to flow in these areas, through water extraction or river regulation, have resulted in many changes to the vegetation including loss of biodiversity and mass invasions of exotic species. Despite increasing pressure for water resource development in 'dryland' regions, relatively little is known regarding the effects of highly variable flows on the vegetation dynamics of arid floodplains, particularly in Australia. This thesis addresses this knowledge gap by examining the role of flow in the vegetation dynamics of a large arid floodplain in central Australia: the Cooper Creek floodplain. The effects of flow on plant community dynamics, from an organism level to that of the landscape, are examined across a range of spatial and temporal scales. Results are presented from a two year temporal vegetation survey during which time two flood pulse events of differing sizes occurred. A large-scale spatial survey was also conducted to determine the effects of flood history on spatial variation in plant community composition and structure. The composition of the soil seed bank and its contribution to vegetation dynamics were additionally investigated through a series of germination trials. Amongst common arid floodplain plants, life history traits that enable persistence under variable hydrological conditions were also considered via several experiments aimed at determining the effects of flow on the outcomes of various life history stages including germination, growth and dispersal. Throughout the study, results are presented for plant groups that were predefined on the basis of life form, life span and taxonomic divisions within these categories. Plant community composition and structure in the Cooper Creek floodplain exhibits significant shifts both temporally, in response to flood pulse wetting and drying, and spatially, in response to flood history. Flood pulse inundation has the potential to influence each life history stage across the range of plant groups present and the outcomes of these appear to be determined by hydrological attributes such as flood pulse timing, duration and rate of drawdown. Vegetation consequently exhibits gradual zonation on a gradient of flood frequency along which plant groups occur at predictable locations depending on their life history traits and recent hydrological conditions. A substantial proportion of species display ruderal life history traits including large, persistent soil seed banks and rapid life cycles which enable escape in time from the stresses associated with flooding and drought. These species, mostly comprising annual monocots and forbs, are widespread throughout the landscape and their presence in the extant vegetation is related primarily to the time since the last flood pulse event and the hydrological attributes of this. Perennial species, particularly shrubs, do not appear to rely similarly on the soil seed bank for recruitment and their distribution in the floodplain vegetation is likely to be determined more by their ability to tolerate either flooding or drought. Overall, this study demonstrates that flow, despite its variability, has an overriding influence on vegetation dynamics in the arid floodplain of the Cooper Creek. The spatial and temporal variability of flow maintains a heterogeneous mosaic of plant communities of differing composition and structure. Given this close relationship between flow and vegetation dynamics, anthropogenic alterations to flow are likely to result in changes to the vegetation including homogenisation of plant communities across the floodplain landscape and eventual loss of biodiversity.

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15

Capon, Samantha Jane. "Flow Variability and Vegetation Dynamics in a Large Arid Floodplain: Cooper Creek, Australia". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/366451.

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Abstract (sommario):

Throughout arid and semi-arid inland Australia, many extensive floodplains occur in association with rivers which are amongst the most hydrologically variable in the world. As rainfall in these areas is characteristically low and patchy, conditions in Australia's 'dryland' floodplains fluctuate unpredictably between extended periods of drought and huge floods that transform vast areas into wetlands, often for months at a time. Vegetation in these floodplains is commonly dominated by short grass and forb associations and patches of open succulent shrubland which are attributed with high ecological and socio-economic values due to their provision of habitat to a diverse array of terrestrial and aquatic fauna and their productive native pasture growth. In temperate and tropical floodplains, a substantial number of studies have shown that plant community composition and structure is determined primarily by flow and alterations to flow in these areas, through water extraction or river regulation, have resulted in many changes to the vegetation including loss of biodiversity and mass invasions of exotic species. Despite increasing pressure for water resource development in 'dryland' regions, relatively little is known regarding the effects of highly variable flows on the vegetation dynamics of arid floodplains, particularly in Australia. This thesis addresses this knowledge gap by examining the role of flow in the vegetation dynamics of a large arid floodplain in central Australia: the Cooper Creek floodplain. The effects of flow on plant community dynamics, from an organism level to that of the landscape, are examined across a range of spatial and temporal scales. Results are presented from a two year temporal vegetation survey during which time two flood pulse events of differing sizes occurred. A large-scale spatial survey was also conducted to determine the effects of flood history on spatial variation in plant community composition and structure. The composition of the soil seed bank and its contribution to vegetation dynamics were additionally investigated through a series of germination trials. Amongst common arid floodplain plants, life history traits that enable persistence under variable hydrological conditions were also considered via several experiments aimed at determining the effects of flow on the outcomes of various life history stages including germination, growth and dispersal. Throughout the study, results are presented for plant groups that were predefined on the basis of life form, life span and taxonomic divisions within these categories. Plant community composition and structure in the Cooper Creek floodplain exhibits significant shifts both temporally, in response to flood pulse wetting and drying, and spatially, in response to flood history. Flood pulse inundation has the potential to influence each life history stage across the range of plant groups present and the outcomes of these appear to be determined by hydrological attributes such as flood pulse timing, duration and rate of drawdown. Vegetation consequently exhibits gradual zonation on a gradient of flood frequency along which plant groups occur at predictable locations depending on their life history traits and recent hydrological conditions. A substantial proportion of species display ruderal life history traits including large, persistent soil seed banks and rapid life cycles which enable escape in time from the stresses associated with flooding and drought. These species, mostly comprising annual monocots and forbs, are widespread throughout the landscape and their presence in the extant vegetation is related primarily to the time since the last flood pulse event and the hydrological attributes of this. Perennial species, particularly shrubs, do not appear to rely similarly on the soil seed bank for recruitment and their distribution in the floodplain vegetation is likely to be determined more by their ability to tolerate either flooding or drought. Overall, this study demonstrates that flow, despite its variability, has an overriding influence on vegetation dynamics in the arid floodplain of the Cooper Creek. The spatial and temporal variability of flow maintains a heterogeneous mosaic of plant communities of differing composition and structure. Given this close relationship between flow and vegetation dynamics, anthropogenic alterations to flow are likely to result in changes to the vegetation including homogenisation of plant communities across the floodplain landscape and eventual loss of biodiversity.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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16

Conran, Leigh Garde. "Establishment vegetation patterns in an artificial urban wetland as a basis for management". Title page, contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09ENV/09envc754.pdf.

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17

Stenhouse, Renae N. "Ecology and management of bushland in Australian cities". University of Western Australia. School of Earth and Geographical Sciences, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0027.

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[Truncated abstract] Native vegetation (bushland) in urban areas remains in small, isolated patches embedded within a matrix of human-dominated land uses. Bushlands in urban areas have high biodiversity conservation and social values, and there has been a local-level movement towards protecting and managing urban bushlands in Australia. This thesis aims to test principles, theories and concepts relating to the ecology and management of bushland fragments in Australian cities ... A commonly used qualitative scale was compared with an ecologically based, quantitative technique developed in the research. The qualitative scale was found to be a reliable proxy for assessing vegetation condition, while also being more user-friendly for community groups and other bushland managers. The human-caused disturbances and weed cover in urban bushlands indicate a need for management intervention. Local government has an important role in local biodiversity management, yet there has been little research on this topic ... Positive partnerships developed where local governments have taken a ‘contract model’ approach to volunteer coordination, have a number of expectations of volunteer groups, and provide the groups with relatively high level of assistance. Also important is a local government that supports, respects, trusts and communicates with the community group, and recognises volunteers’ skills, knowledge and contributions. With increased resources allocated to local government bushland management and conservation, and coordination with community groups, the full potential of local bushland management would be realised.

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18

Horsnell, Tara Kathleen. "Quantifying thresholds for native vegetation to salinity and waterlogging for the design of direct conservation approaches". University of Western Australia. School of Environmental Systems Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0082.

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A field-based project was undertaken to develop and test a mechanism which would allow for the correlation of the health of vegetation surrounding playa lakes in south-west Australia with the natural variation in salinity and waterlogging that occurs spatially and temporally in natural systems. The study was designed to determine threshold ranges of vegetation communities using moderately extensive data over short temporal periods which will guide the design of potential engineering solutions that manipulate hydrological regimes to ultimately conserve and protect native vegetation. A pair of playa lake ecosystems, surrounded by primary production land, was modelled with hydro-geological data collected from March 2006 to March 2007. The data was used to determine the hydroperiods of vegetation communities fringing playa lakes and provide insight into the areas and species that are most affected by extreme rainfall events which are hypothesised to have a significant, rapid deleterious effect on the ecosystems. The methodology was multi-faceted and included; a detailed topographical survey; vegetation surveys; hydrological and hydro-geological monitoring over a 12 month period. 4 The hydro-geological data and vegetation data was linked with the topographical survey at a high resolution for spatial analysis in a Geographic Information System (GIS) to determine the degree of waterlogging experienced by vegetation communities over the monitoring period. The study has found that the spatial and temporal variability of hydroperiods has been reduced by rising groundwater levels, a result of extensive clearing of native vegetation. Consequently populations are becoming extinct locally resulting in a shift in community composition. Extreme summer rainfall events also have a significant impact on the health of vegetation communities by increasing the duration of waterlogging over an annual cycle and in some areas expanding the littoral zone. Vegetation is most degraded at lower positions in the landscape where communities are becoming less diverse and dominated by salt tolerant halophytic species as a result of altered hydrological regimes. Some species appear to be able to tolerate groundwater depths of less than 2.0 m from the surface, however there are thresholds related to the duration at which groundwater is maintained at this depth. Potential engineering solutions include groundwater pumping and diverting water through drains to maintain sustainable hydroperiods for vegetation in areas with conservation value. The effectiveness and efficiency of the engineering solutions can be maximised by quantifying thresholds for vegetation that include sustainable durations of waterlogging. The study has quantified tolerance ranges to salinity and waterlogging with data collected over 12 months but species may be experiencing a transition period where they have 5 sustained irreversible damage that will result in their eventual mortality. With long-term monitoring, the methodology developed and tested in the study can be used to quantify the long-term tolerance ranges that are important for the application of conservation approaches that include engineering solutions.

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19

Semeniuk, Christine. "Evolution of wetland habitats and vegetation associations on a holocene coastal plain, Southwestern Australia". Thesis, Semeniuk, Christine (2002) Evolution of wetland habitats and vegetation associations on a holocene coastal plain, Southwestern Australia. PhD thesis, Murdoch University, 2002. https://researchrepository.murdoch.edu.au/id/eprint/51816/.

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This study takes a multi-disciplinary approach to the investigation of a genetically related suite of wetlands, the Becher Suite, on the Swan Coastal Plain in southwestern Australia. The wetlands occur on a vegetated beachridge plain which forms the surface of an accretionary cuspate foreland, the Becher Cuspate Foreland. The Becher Cuspate Foreland is the largest sedimentary coastal deposit on the southwestern Australian coast which, by nature of its formation, contains a 7,000 year Holocene history of sea level changes, shoreline and beachridge plain development, and climate history. When swales within the beachridge plain became waterlogged or inundated by a rising water table following coastal progradation and a gradually falling sea level, it signalled the commencement of wetland development. Because of the varying geographic relationship between the ground surface and the water table, wetland initiation across the beachridge plain was staggered, commencing circa 4,500 years BP and continuing to circa 600 years BP. Wetland basins were filled with carbonate mud and peat, and over time, sedimentologic, pedogenic, diagenetic and hydrological processes created stratified wetland sedimentary sequences. An increase in the heterogeneity of wetland fill in response to regional climatic processes progressively influenced hydrological functions in and adjacent to wetland basins. The combined effects of a local and variable wetland stratigraphy and plant uptake and release on cation concentrations down profile in sediments, interstitial waters and groundwater, resulted in very localised hydrochemical signatures specific to the type of sedimentary fills, their evolutionary stage, and to their extant vegetation association. The Becher Suite wetlands demonstrate that less than a metre of wetland sediment not only sets the wetland apart from larger scale regional processes, but establishes a physical, chemical and biological system which evolves independently. Vegetation across the range of wetlands in the study area exhibits an increase in complexity of pattern and form with increased age of wetland. In the youngest wetlands, the vegetation is uniform sedgeland. With increasing age, the pattern becomes concentrically zoned with two, three and four zones, comprising mixed sedgeland, herbland, shrubland, or low forest, and an outer zone of closed grass tree. The fluctuations in plant communities recorded over 10 years, as well as that recorded geohistorically in the pollen record indicate expansion and contraction of vegetation assemblages in response to fluctuating hydrological conditions within the wetland basins, and in the long term, in response to some climate forcing.

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20

Hearman, Amy. "A modelling study into the effects of rainfall variability and vegetation patterns on surface runoff for semi-arid landscapes". University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0047.

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[Truncated abstract] Generally hydrologic and ecologic models operate on arbitrary time and space scales, selected by the model developer or user based on the availability of field data. In reality rainfall is highly variable not only annually, seasonally and monthly but also the intensities within a rainfall event and infiltration properties on semi-arid hillslopes can also be highly variable as a result of discontinuous vegetation cover that form mosaics of areas with vegetation and areas of bare soil. This thesis is directed at improving our understanding of the impacts of the temporal representation of rainfall and spatial heterogeneity on model predictions of hydrologic thresholds and surface runoff coefficients on semi-arid landscapes at the point and hillslope scales. We firstly quantified within storm rainfall variability across a climate gradient in Western Australia by parameterizing the bounded random cascade rainfall model with one minute rainfall from 15 locations across Western Australia. This study revealed that rainfall activity generated in the tropics had more within storm variability and a larger proportion of the storm events received the majority of rain in the first half of the event. Rainfall generated from fontal activity in the south was less variable and more evenly distributed throughout the event. Parameters from the rainfall analysis were then used as inputs into a conceptual point scale surface runoff model to investigate the sensitivity of point scale surface runoff thresholds to the resolution of rainfall inputs. This study related maximum infiltration capacities to average storm intensities (k*) and showed where model predictions of infiltration excess were most sensitive to rainfall resolution (ln k* = 0.4) and where using time averaged rainfall data can lead to an under prediction of infiltration excess and an over prediction of the amount of water entering the soil (ln k* > 2). For soils susceptible to both infiltration excess and saturation excess, total runoff sensitivity was scaled by relating drainage coefficients to average storm intensities (g*) and parameter ranges where predicted runoff was dominated by infiltration excess or saturation excess depending on the resolution of rainfall data were determined (ln g* <2). The sensitivity of surface runoff predictions and the influence of specific within storm properties were then analysed on the hillslope scale. '...' It was found that using the flow model we still get threshold behaviour in surface runoff. Where conditions produce slow surface runoff velocities, spatial heterogeneity and temporal heterogeneity influences hillslope surface runoff amounts. Where conditions create higher surface runoff velocities, the temporal structure of within storm intensities has a larger influence on runoff amounts than spatial heterogeneity. Our results show that a general understanding of the prevailing rainfall conditions and the soil's infiltration capacity can help in deciding whether high rainfall resolutions (below 1 h) are required for accurate surface runoff predictions. The results of this study can be considered a contribution to understanding the way within storm properties effect the processes on the hillslope under a range of overall storm, slope and infiltration conditions as well as an improved understanding of how different vegetation patterns function to trap runoff at different total vegetation covers and rainfall intensities.

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21

Growcock, Andrew Jason William. "Impacts of Camping and Trampling on Australian Alpine and Subalpine Vegetation and Soils". Thesis, Griffith University, 2006. http://hdl.handle.net/10072/366707.

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This thesis examines the impact of recreational activities, specifically camping and trampling, on alpine and subalpine vegetation communities in Kosciuszko National Park, Australia. A survey approach was first used to determine visitor use levels and types of recreation activities within the main alpine area. An experimental methodology was then used to quantify the relationship between use and damage from camping and trampling to vegetation and soils. Specific questions addressed were: (1) what are the visitor numbers, demographics, activities and patterns of visitation to the Kosciuszko alpine area and have they changed since previous estimates?; (2) what is the relationship between levels of use and damage for camping in undisturbed alpine and subalpine vegetation communities and does this vary between tent and activity areas?; (3) (a) what is the relationship between levels of use and damage for trampling in the undisturbed alpine and subalpine vegetation communities when trampled once and (b) are thresholds and/or the relationship altered when trampling is repeated in the following year?; (4) what is the relationship between use and damage from trampling to plant communities following a large-scale disturbance (bushfire) and do natural processes during the following year of recovery eclipse any recreation impacts?; and (5) what recommendations can be made to minimise impacts of trampling and camping in high altitude sites in the Australian Alps? Research assessing the impact of recreation on the environment is important for conservation of protected areas. Recreation can affect a range of environmental components including vegetation and soils. These impacts can be measured using a range of parameters including vegetation cover, composition and height and soil compaction. When assessing the impact of recreation on vegetation and soils, four factors need to be considered: (1) amount of use; (2) type of use and behaviour; (3) timing of use; and (4) environmental characteristics. In this thesis it is proposed that low levels of recreation use may not cause significant damage to vegetation until a primary threshold point is reached where increasing use results in rapidly increasing amounts of damage. A second threshold may then be found above which increasing use does not result in significantly more damage. Type and intensity of impacts can vary among different activities so the effects of camping and trampling (which are popular activities in the area) were both examined at varying intensities of use. As vegetation types may also vary in their response, the impact of activities on different communities were compared. Finally, the effect of trampling after large scale fires was examined. Kosciuszko National Park is a unique mountain area that has been used for a variety of activities since European settlement. Tourism is now one of the largest land uses of the Park with indications of continued growth from the mid 1950's through until the early 1990's. As the area has high conservation values, minimising the amount of disturbance to the environment caused by tourists is important for the long term management of the Park. Based on an extensive analysis of visitor survey data collected prior to the thesis in the 1999/2000 non-winter period, it was possible to characterise recreational use of the largest alpine area in Australia. Like many protected areas around the world, recreational use in Kosciuszko National Park is increasing during the non-winter period. During this survey, 102 000 visitors were estimated as entering the Kosciuszko alpine area with approximately 47 000 visitors undertaking activities of a half a day or more. This is a 10% increase since the previous estimate from the 1990/91 non-winter period. A variety of activities are undertaken within the area including sightseeing, day walking, mountain biking and camping. For camping, most trips were undertaken by small groups for short periods. Therefore the impacts to vegetation from one and three nights camping by groups of four people were assessed using an experimental approach. Camping for both one and three nights affected vegetation height, but to different extents. After three nights camping, there was a decrease in vegetation height in the tent and activity areas while after one night camping, a decrease in vegetation height only occurred in the tent area. Camping for three nights caused a short term increase in dead material, however six weeks after camping there was no difference in the cover of dead material among the control, tent or activities areas indicating that the effect was short lived. One night camping did not result in any significant increase in dead material. Bushwalking is one of the most popular activities to be undertaken in the Australian Alps including the Kosciuszko alpine area. Many visitors undertaking walks during this time depart hardened tracks in order to reach destinations such as mountain peaks and glacial lakes. An obvious impact of this trampling is the creation of pads and trails as the vegetation cover is replaced by bare soil that then becomes compacted and/or erodes. The thresholds before signs of disturbance occur as a result of trampling vary among vegetation communities and among parameters measured. Generally, primary thresholds were exceeded after moderate use with damage still evident one year later. Reduced vegetation height occurred at lower levels of use, but recovered quickly. Vegetation cover showed limited recovery once damaged. This was particularly apparent for bog communities, which also had very low resistance to damage. Repeat trampling in the following year compounded the damage and lowered the primary thresholds. Impacts and thresholds from trampling in subalpine areas within weeks of the landscape level bushfires in 2003 differed from those in the undisturbed community. Where areas had been burnt, low levels of trampling caused exposure and loss of underlying bare soils with secondary thresholds reached at low to moderate use. These thresholds occurred for both extensively burnt and partially burnt areas. The damage caused by trampling however, was rapidly eclipsed by natural processes with no significant effects after one year. When examining the impacts of trampling in extensively burnt subalpine grasslands one year after the bushfires the thresholds for cover were again lower than undisturbed conditions even though there was substantial vegetation recovery from the fires. Low to moderate use was required to exceed the primary threshold for vegetation cover with a secondary threshold achieved after moderate use. Twelve months of recovery had however, allowed soils to become more cohesive with moderate to high trampling use now required to cause significant losses of soil. This research has shown that the identification of two thresholds of disturbance will be beneficial for management decision making. A primary threshold will define the upper limit of use for dispersed recreational use while a secondary threshold will define when concentrated use should occur. This information is valuable, as while the resistance of the vegetation communities examined in this research was moderate in some communities, resilience was always low. As such, recovery from disturbance will be slow and damage should therefore be minimised as much as possible.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental and Applied Science
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22

Evans, Lisa J., e n/a. "The Influence of fluvial geomorphology on riparian vegetation in upland river valleys: south eastern Australia". University of Canberra. School of Resources Environmental and Heritage Sciences, 2003. http://erl.canberra.edu.au./public/adt-AUC20050404.112525.

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Healthy riparian vegetation has a positive impact on the adjacent river. Unfortunately, riparian vegetation is often threatened by human impacts such as dam construction and clearing. To gain the knowledge underlying the effects of such impacts and to aid riparian rehabilitation, the objective of this thesis was: to determine riparian vegetation association with, and response to, variation in fluvial geomorphology over several scales and consequently to fluvial disturbance. Only woody riparian plant species were considered. Flood disturbance was the unifying theme of this thesis. Linked to this theme and arising from the main objective was the supposition that plant interactions with the abiotic environment, but not biotic interactions between species, control riparian species distribution because of frequent fluvial disturbances. Woody riparian vegetation and riverine environmental variables were recorded along the upper Murrumbidgee River at three spatial scales based on a geomorphic hierarchy for Chapter 2. Multivariate analysis was used to group species and to associate environmental variables with vegetation at the three spatial scales. Observations at the two larger scales, of river segment (site) and riparian reach (transect), identified a river-longitudinal speciescomposition gradient associated with geology, river width and stream channel slope. Observations at the smallest scale of geomorphic units (plot) identified a lateral riparian gradient and also the longitudinal gradient; these gradients were associated with geomorphic variation, land use, plot elevation and also river longitudinal variables. Using the same data set, but varying the spatial scale of analysis caused the species composition pattern to change between scales. Increase in scale of observation, that is from geomorphic unit to reach and segment scales, resulted in disproportionate importance of rarer species and decreased importance of some key riparian species at the larger scales. It would appear that in this instance the geomorphic unit scale best described patches of different species composition because this scale had high spatial resolution and was also able to identify multiple gradients of environmental variation. It was recommended that riparian sampling take place at scales that represent dominant gradients in the riparian zone. These gradients are represented by geomorphic scales, indicating the appropriateness of using geomorphic based scales for observation of riparian vegetation. Chapter 3 considered whether there is a geomorphic template upon which riparian vegetation is patterned and whether it is associated with process variables, such as flooding and soil type. This question was investigated at different spatial scales in three ways: i) by an experiment to determine whether soil nutrient condition affects plant growth; ii) by graphical analysis of trends between geomorphic units, species and process variables; and iii) by analysis of vegetation distribution data. The smallest scale (meso) found experimental differences in plant growth because of soil type. Plants growing in sand had the lowest performance, with an average plant Relative Growth Rate (RGR) of 0.01, compared to plants growing in soils with small amounts of silt or clay particles, with an average plant RGR of 0.04. This pattern was attributed to differences in nutrients. Clear relationships were demonstrated at the larger geomorphic unit scale between species distribution and process variables. For example, hydrology and substratum type were found to be associated with geomorphic units and species. The largest scale considered in Chapter 3 was the riparian reach scale. At this scale species were clearly grouped around reach type. Therefore, geomorphology was considered to be a template for riparian species distribution. Findings in this chapter suggested that geomorphic variables should be good predictors of riparian species distribution. This hypothesis was tested and supported in Chapter 6. The experiments reported in Chapter 4 aimed to determine whether inundation depth and duration affected plant performance and survival for five common riparian zone species. Riparian seedling patterns in the field were also compared with experimental results to test whether species performance was reflected by field distribution. The experiments that were conducted included an inundation period and depth experiment, and a survival period test whilst under complete inundation. Biomass and height relative growth rates were determined, and the results were analysed using factorial Analysis of Variance. Obligate riparian species (Callistemon sieberi, Casuarina Cunninghamiana, Leptospermum obovatum) were found to be tolerant of inundation duration and depth, to the point where inundation provided a growth subsidy. On the other hand, non-obligate riparian species (Acacia dealbata, Kunzea ericoides) were either just tolerant of inundation or showed a negative growth response. For instance, C. sieberi demonstrated an average height RGR of 0.04 after complete inundation and 0.007 when not inundated, while A. dealbata had an average height RGR of 0.001 after complete inundation and 0.01 when not inundated. These experimental findings were found to closely reflect both seedling and adult plant distribution in the field such that inundation tolerant species were found close to the river and intolerant species further away. Thus, the conclusion was drawn that riparian species establishment and distribution is affected by inundation and that change to the flood regime could have serious impacts on riparian zone plant composition. The other aim of this chapter was to determine whether optimum germination temperatures were associated with flood or rainfall. Growth chamber germination trials were conducted at air temperatures of 15�C, 20�C and 25�C to determine the 'best' germination temperature. These germination patterns at different temperatures were then related to annual variation in field temperature, flooding period and rainfall. No evidence was found to suggest a relationship between ideal germination temperature and flood season, rather it was suggested that germination was patchy through time and may simply reflect recent rainfall. Investigations that were reported in Chapter 5 aimed to elucidate relationships between species and flow velocity variables. Two experiments were conducted: i) a flume experiment to determine the effect of flow velocity on plant growth; and ii) an experiment to observe the response of plants to damage (imitating flood damage) and inundation. Field observations of species distribution and flow velocity related variables were also conducted to put the flume results into a real-world context. Treatments for the flume experiment were fast flow velocity (0.74 m s-1), slow velocity (0.22 m s-1) and no velocity (control) but still inundated. All treatments were flooded completely for four days. Subsequent biomass and height relative growth rates were determined, and the results were analysed using factorial Analysis of Variance. Results were unexpected, given that obligate species exposed to the fastest velocity had the highest growth rate with an average height RGR of 0.046, compared to plants in still water, which grew the least with an average height RGR of 0.013. It was hypothesised that this response was because relatively greater carbon dioxide and oxygen levels were available in the moving water compared to the still water. With regard to shoot damage, the species that were nonobligate riparian species lost more leaves from velocity treatment than the obligate riparian species. The cut and flood experiment found growth of the obligate species (Casuarina cunninghamiana) to be greater after cutting than the non-obligate species. Flooding was not found to have an effect in the cut and flood experiment, probably because the period to sampling after flood treatment was longer (4 weeks) than other flooding experiments (3 weeks). Field observations were found to support the experimental findings, with a gradient of species across the riparian zone that reflected potential flood velocities. Therefore, velocity is one of a suite of riparian hydrological factors that are partially responsible for the gradient of species across the riparian zone. Potentially the absence of flooding could result in a homogeneous mix of species, rather than a gradient, except on the very edge of the river. The study that was reported in Chapter 6 investigated a technique for predicting riparian vegetation distribution. One of the aims of this investigation was to address a current riparian rehabilitation shortfall, which was how to objectively select species to plant for rehabilitation. Field data were collected from three confined river valleys in south-eastern New South Wales. Using data on plant species occurrence and site and plot measures of soils, hydrology and climate, an AUSRIVAS-style statistical model, based on cluster and discriminant analysis, was developed to predict the probability of species occurrence. The prediction accuracy was 85 % when tested with a separate set of plots not used in model construction. Problems were encountered with the prediction of rarer species, but if the probability of selection was varied according to the frequency of species occurrence then rarer species would be predicted more often. Various models were tested for accuracy including three rivers combined at the geomorphic unit (plot) scale and riparian reach (transect) scale in addition to a Murrumbidgee River plot scale model. Surprisingly, the predictive accuracy of the all rivers and single river models were approximately the same. However, the difference between the large scale and small scale models pointed to the importance of including small scale flood-related parameters to predict riparian vegetation. When these riparian predictions were compared to predictive outcomes from a hill slope model, which was assumed to be affected by fewer disturbances (i.e. flooding), predictive accuracies were not very different. Overall though, predictive accuracy for riparian vegetation was high, but not good enough to support the supposition that riparian vegetation is abiotically controlled because of frequent flood disturbance. Nevertheless, geomorphology and consequently flood effects are still important for the determination of the riparian community composition. Overall, riparian vegetation was found to be closely linked to its environment (evidenced in Chapters 2, 3, 4, 5) in a predictable manner (Chapter 6). Species pattern relied on flood disturbance affecting species distribution. Some riparian species were found to be highly tolerant of flooding and gained a growth advantage after flooding (Chapters 4 and 5). Therefore, flood tolerance was important for the formation of a species gradient across the riparian zone. These species tolerances and growth requirements reflect riparian geomorphic pattern (Chapter 3), which was suggested to form a template on which riparian vegetation is structured.

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23

Williams, Richard G. "Floristic recovery of native vegetation after petroleum exploration in the Otway Basin, S.E. South Australia /". Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09SM/09smw7259.pdf.

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24

Uddin, S. M. Mijan. "Understanding soil water repellency under native vegetation in Australia: An empirical and molecular dynamics approach". Thesis, Uddin, S. M. Mijan (2017) Understanding soil water repellency under native vegetation in Australia: An empirical and molecular dynamics approach. PhD thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/40269/.

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Abstract (sommario):

Soil water repellency (SWR) is a major land management issue across southern Australia and inhibits the infiltration of water into soil with effects on the germination of crops and pastures and run-off in agricultural and forested land. SWR is a natural phenomenon and generally occurs in the surface layers of sandy soils where hydrophobic materials mostly of plant origin occur as particulate organic matter and as waxy coatings on soil particles. Although its incidence and severity have been anecdotally related to the previous native vegetation little is known about the specific organic compounds that may derive from this vegetation. Previous studies have concentrated on characterizing the contribution of soil organic matter, and this and the fact that soils are complex mixtures of a broad range of organic components may have obscured the contribution of a small concentration of compounds from the native species to SWR. Moreover, the precise distribution of these compounds (e.g., as coatings or in interstices between soil particles) and their contribution to SWR has not been quantified. Although analysis of soil solvent extracts can identify the relative amounts of individual compounds, it is often difficult to determine the relative importance of all components in inducing SWR. It is even harder to determine synergistic effects from combinations of components. Experimental studies provide a broad understanding of the bulk effects of hydrophobic molecular coatings but do not provide a molecular level understanding of the coating structure or of its kinetic and/or thermodynamic stability. The molecular arrangement of those organic compounds on the soil particles have been shown to have implications for both the incidence and dynamics of SWR. Thus the present study employed a range of approches to understand SWR in native vegetation: i) quantifying the contribution of canopy derived exudates from native tree species to SWR, ii) discerning the contribution of organic matter in different pools (e.g., on particle surfaces, as interstitial matter) to SWR and iii) examining the physical interaction of the organic molecules (without and with water) with soil mineral surfaces. Canopy derived exudates were captured using an improvised technique, and organic compounds were extracted using nonpolar and polar solvents. In order to discern the contribution of different carbon pools to SWR, soils were separated into mineral and interstitial matter. Soils were extracted using a sonication technique. Individual and combinations of compounds were loaded onto acid washed sand (AWS) using a rotary evaporator. This experimental loading and measurement was complemented by fully atomistic molecular dynamics simulations with Materials Studio v 7.0 to understand the physical interaction of the molecules with mineral surfaces. A range of different organic compounds that are widely reported in the incidence of SWR were detected in the canopy derived exudates and soil extracts. They were mostly long-chain alkanes, fatty acids, phytols, phytanols, amides, aldehydes, ketones, terpenoids, steroids, and some complex ring containing structures. Though there was similarity in the composition of both the nonpolar and polar compounds of exudates of Banksia menziesii, Eucalyptus marginata, Xanthorrhoea preissii and Allocasuarina fraseriana, the concentration level of the chemical species was found to be significantly different. The concentrations were found to differ over the sampling period. For example, docosanoic acid was found to be dominant in the summer for B. menziesii and X. preissii. while in E. marginata and A. fraseriana it was evident in the winter. Moreover, the concentration level of the chemical species derived from the soil extracts were also found to be significantly different between the species of A. fraseriana, E. marginata, E. wandoo and B. menziesii. Notably, the main difference between A. fraseriana and the other three species (E. marginata, E. wandoo and B. menziesii) was the presence of long chain fatty acids and fatty alcohols. The concentration of the compounds was even different in different soil components (e.g., minerals and interstitial matter) of the soil matrix. For example, the concentration level of the individual compound derived from the bulk soil was similar to the total concentration level of the compound derived from both the coarse mineral materials and interstitial matters. The molecular level arrangement of various hydrophobic molecules with mineral surfaces also varied. For example, amphiphilic molecules at surface density of 2.3 molecs/nm2 were found in a tilted arrangement on kaolinite while on quartz surfaces they formed layered arrangements. However, silica did not favor a certain order of arrangement of the molecules due to its amorphous surface. The surface characteristics and polarity (abundance of OH groups) of the substrate (kaolinite > silica) were found to significantly modify the organo-mineral interactions. Different biogenic volatile organic compounds (BVOCs) or terpenoids commonly observed in vegetation smoke or forest fire, were not found to induce SWR. Moreover, the long chain amphiphilic molecules exhibited a balance between molecule-molecule and molecule-surface interactions on the quartz surface that supported surface adhesion, which in turn led to the formation of a hydrophobic layer. Furthermore, soil moisture or the addition of water molecules was found to significantly modify the conformation of molecules at the organo-mineral interfaces. For example, the polar kaolinite and silica surfaces were found to easily wet-up and reorganization of amphiphilic molecules on the surfaces took place following aquation. The stronger interaction between water and organic molecules can thus be inversely correlated to organo-mineral interaction on soil particles.

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25

Dong, T. T. Trang. "Chemical composition and toxicity of emissions from burning five vegetation types of Western Australia under experimental combustion conditions". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2019. https://ro.ecu.edu.au/theses/2180.

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Abstract (sommario):

This study investigated the emission factors (EFs) for inorganic gases (CO2, CO, SO2, NO and NO2), carbonyls (formaldehyde, acetaldehyde, acetone, propionaldehyde, butyraldehyde and benzaldehyde), volatile organic compounds (VOCs) and particulate matter (PM2.5 and PM10) from laboratory-based fires of vegetation from five typical vegetation types of Western Australia. Species burnt were three grasslands (Spinifex represented by Triodia basedowii, Kimberley grass represented by Sehima nervosum and Heteropogon contortus, and an invasive grass represented by Ehrharta calycina (Veldt grass)), Banksia woodland and Jarrah forest under different combustion conditions. Chemical composition (water-soluble metals and polycyclic aromatic hydrocarbons – PAHs) and in vitro toxicity of PM2.5 were also measured. Vegetation samples were burnt in a ceramic chamber in varying combustion conditions altered by controlling the vegetation moisture content (<10%, 12–16% and 20–25%) and the air flow rate (0, 1.25 and 2.94 m.s-1). Burns of woodland (Banksia) and forest (Jarrah) had significantly higher EFs for CO, SO2 and PM2.5 compared with those from grassland (Spinifex). Emissions of temperate grass (Veldt) fires were significantly different from those of the tropical grass (Spinifex and Kimberley grasses), with lower EFCO2 and higher EFs for CO, carbonyls and PM2.5. EFs for SO2, NO and NO2 were variable between different vegetation types, indicating variation in the nitrogen and sulphur content of the fuels. The EFs for most carbonyls were similar between most vegetation types, with the exception of Veldt grass. Functions which may be useful to predict emissions of infrequently measured carbonyls (acetaldehyde, acetone and propionaldehyde) from the EF for formaldehyde, a commonly measured and reported substance, were also proposed. Fifteen VOCs were identified in the smoke, but concentrations were too low to be quantified. Benzene, toluene, styrene and indene were the most frequently detected VOCs. Moisture content did not strongly influence the modified combustion efficiency (MCE) and EFs for gaseous pollutants, but significantly affected the EF for PM2.5 with higher emissions from burns of moister vegetation. Increasing the air flow rate significantly increased the emissions of most pollutants. However, combustion conditions did not strongly affect the PM2.5 chemical composition. The MCE, EFs for CO and CO2 results in this study were similar to values reported from field measurements for similar vegetation types in Australia, indicating the applicability of these laboratory-based results. Emission factors were different to the profiles generated from vegetation fires in other parts of the world. Toxicity of PM2.5 on human lung epithelial (A549) cells was assessed using cell viability and cytokine production measurements. Responses on cell viability were associated with K and Na concentrations in PM2.5, whilst the cytokine production of cells was more affected by the PM2.5-bound PAH, Al, Cu and Mn concentrations. Toxicity between vegetation types was different, which might be due to the differences in chemical composition of PM2.5. PM2.5 emitted from Jarrah burns appeared to have the highest toxicity on epithelial cells, followed by those from Banksia, Veldt grass and Spinifex. The findings of this study on toxicity of PM2.5 demonstrate the adverse impact on human health of particulate from bushfires and emphasise the importance of vegetation type on toxicological outcomes of bushfire-derived PM2.5. The EFs obtained in this study can be used in models to estimate the emissions from bushfires in Australia, particularly Western Australia. Results on toxicity of PM2.5 provide information for relevant government agencies to preliminarily evaluate the risk to human health, especially for firefighters and communities in close proximity to bushfire events.

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26

Munyenyembe, F. E., e n/a. "Bird density and species richness in suburban Canberra, Australia : relationships with street vegetation, age of suburb and distance from bird source areas of native vegetation". University of Canberra. Applied Science, 1985. http://erl.canberra.edu.au./public/adt-AUC20061027.115542.

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27

Jayawardana, Chandamali University of Ballarat. "Littoral macroinverterbrates in relation to native and exotic riparian vegetation in streams of central Victoria, Australia". University of Ballarat, 2006. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/12773.

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Abstract (sommario):

"Exotic willows (Salix spp.) are widespread riparian tree species of streams in temperate Australian and New Zealand. In Australian willow speicies are declared weeds of national significance, yet little is known about the novel habitats they create not the impact on aquatic biota of vegetation change following willow management programs ..." [leaf i]
Doctor of Philosophy

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28

Jayawardana, Chandamali. "Littoral macroinverterbrates in relation to native and exotic riparian vegetation in streams of central Victoria, Australia". University of Ballarat, 2006. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/14610.

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Abstract (sommario):

"Exotic willows (Salix spp.) are widespread riparian tree species of streams in temperate Australian and New Zealand. In Australian willow speicies are declared weeds of national significance, yet little is known about the novel habitats they create not the impact on aquatic biota of vegetation change following willow management programs ..." [leaf i]
Doctor of Philosophy

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29

Jayawardana, Chandamali. "Littoral macroinvertebrates in relation to native and exotic riparian vegetation in streams of central Victoria, Australia". Thesis, University of Ballarat, 2006. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/65724.

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Abstract (sommario):

"Exotic willows (Salix spp.) are widespread riparian tree species of streams in temperate Australian and New Zealand. In Australian willow species are declared weeds of national significance, yet little is known about the novel habitats they create not the impact on aquatic biota of vegetation change following willow management programs ..." [leaf i]
Doctor of Philosophy

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30

Zencich, Sandra Jane. "Variability in water use by phreatophytic Banksia woodland vegetation of the Swan Coastal Plain, Western Australia". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2003. https://ro.ecu.edu.au/theses/1328.

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Abstract (sommario):

Seasonal changes exist in source-water utilisation by Banksia woodland species overlying a shallow aquifer on the Swan Coastal Plain in Western Australia These were studied to identify the importance of groundwater as a water source to this vegetation. Intra-and interspecific variation in seasonal water use was investigated across the dominant overstorey and understorey species, with particular emphasis on species of different rooting morphologies. Seasonal water use was investigated across a topographical gradient ranging from a groundwater depth of 2.5 to 30 metres, a scenario representative of the coastal sand-dune system. An examination was also made of the response of woodland vegetation to an induced and rapid temporal separation from the groundwater able, beyond the normal range of groundwater fluctuation. To investigate a species' seasonal water usage, measurements of the naturally occurring stable isotope of hydrogen in water (deuterium, δ2H) were used to distinguish among potential plant water sources. Isotopic ratios from vascular water of the study species were compared with those of potential sources of precipitation, soil moisture and groundwater. The primary assumptions of this method were validated for the study species in laboratory experiments, and field-sampling strategies were developed. Through this process, the water sources available to plants were identified. Mixing models were employed to calculate the proportion of groundwater used. The results of this study confirm that groundwater is an important water source to both overstorey and understorey components of the woodland. Phreatophytic species were characterised by a deep root system, in which the tap root played a significant role in groundwater uptake. These species derived some of their water from groundwater throughout the dry-wet cycle. With the onset of the hot, Mediterranean summer, they increased their use of deep moisture sources, including groundwater. Variability in groundwater usage was observed at the interspecific and intraspecific level. This was dependent on root-system distribution and maximum root depth. For those species capable of using groundwater, the degree to which it was utilised was dependent on the proximity of groundwater (i.e. the depth to the water table), and the availability of moisture in shallower horizons of the soil profile (i.e. the season). For individuals occurring at shallow depth to water (< 8 m), groundwater was an important water source: whereas, at greater depths (≥8 m) its importance decreased as it was used in lower proportions and/or for shorter durations. Comparisons of within-species variation revealed disparities in groundwater usage, and possibly dependency, between the dominant overstorey Banksia species. Banksia ilicifolio, a species confined to habitats where groundwater depth is ≤8 m, was dependent on groundwater during the dry summer period (up to 90% of water used was groundwater) and may be considered a summer obligate phreatophyte. B. attenuata is a summer facultative phreatophyte, occurring where groundwater depth is 2 to >30m with groundwater accounting for between 5 to 75% of water used depending on depth to the water table. These results suggest the possibility of an obligate-facultative phreatophyte distinction. The response of phreatophytic Banksia species to changes in the groundwater regime beyond the normal range of groundwater fluctuation confirmed the seasonal nature of groundwater dependence, and varied sensitivity of individuals according to their position within the sandplain landscape (i.e. proximity to groundwater).

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31

Pettit, Neil. "Factors affecting the recruitment of riparian vegetation on the Ord and Blackwood Rivers in Western Australia". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2000. https://ro.ecu.edu.au/theses/1625.

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Abstract (sommario):

This thesis provides baseline information on the ecological processes involved in the recruitment and regeneration of riparian vegetation. As there has been a paucity of basic ecological studies on riparian vegetation in Australia, the project is broad in scope, and gives a general picture of the factors influencing, the regeneration of riparian vegetation and provides a starting point for more detailed work. The project focuses on factors determining recruitment events and the life history traits of particular species in a river in the cool temperate zone of south western Australia (Blackwood River) and on a river in the dry tropics of the Kimberley region of north-western Australia (Ord River). By studying two contrasting river systems in different climatic zones, the influence of the physical environment and biotic factors in vegetation persistence and recruitment in the riparian zone can be distinguished. This will contribute to providing an ecological basis for the rehabilitation and management of riparian vegetation in these types of systems. The structure of the vegetation on the Blackwood River consists of an overstorey dominated by Eucalyptus rudis, with a shrub understory at ungrazed sites and with annual species dominant in areas grazed by livestock. On the Ord River there is a much more diverse overstsorey and a species-poor understorey dominated by perennial grasses. Fencing to exclude stock, or to at least manage grazing, is a fundamental step towards achieving rehabilitation of degraded riparian sites where recruitment may be severely limited. Exclosure experiments in the Blackwood River show little improvement in recruitment after three years, with only minor increases in the occurrence and cover of native species. Establishment of these species may be difficult with the increase in abundance of exotic grasses and annual herbs which has occurred as a result of the absence of grazing. These results are however for the short-term and a much longer period is required to look at the vegetation dynamics and successional processes of these sites. In the riparian zone, regeneration of the vegetation from soil seedbanks is important for annual species of herbs and grasses but of only minor significance for perennial species. For perennial species, particularly the overstorey, direct seedfall from existing vegetation occurs, and enhanced dispersal by floating downstream with flood debris is a consequential recruitment mechanism. Hence, reproductive phenology of the four species monitored in this study appears to be well adapted to the hydrological regime on the respective rivers. Position in the riparian landscape where seedlings manage to establish is strongly related to environmental conditions that provide adequate moisture but protect seedlings from flooding. Historical flow records can be used to develop an understanding of the natural flow regime for a particular river which can then be related to patterns of vegetation development in terms of reproductive phenology, seedling establishment and population structure, as well as plant community patterns in the riparian zone. Variability in natural flow regimes, as a disturbance, can therefore be used in conjunction with other abiotic and biotic factors in developing a model of vegetation dynamics for the riparian zone. For example, the regime of intermittent high frequency large flood disturbances on the Ord River prevents the establishment of stable states of the vegetation and the ecosystem is characterised by long periods of transition between short-lived stable states. This riparian ecosystem is thus driven by physical (allogenic) processes rather than by vegetation successional (autogenic) processes. In contrast, lower energy seasonal flooding on the Blackwood River allows mature stands of trees to develop throughout the river profile. Recruitment is continual, although species can also respond to large flood events. This disturbance regime results in long periods of stable status with short periods of transition. The vegetation is thus subject to longer periods of autogenic processes and, because of lower frequency flooding disturbance, shorter periods of allogenic processes. These results highlight the effect of the different fluvial regimes of the two rivers on the respective vegetation dynamics. Management of the riparian vegetation should therefore take into account the frequency and rate of change in the vegetation and that disturbed states and long periods of transition between states, particularly on the Ord River, are part of the natural process. This would suggest that altering the natural flow regimes, such as through river regulation, would have significant effects on riparian vegetation dynamics. This work has relevance to all aspects of riparian zone vegetation, including management of natural systems unaffected by man-made disturbances, for systems affected by stock grazing, for areas requiring rehabilitation and on regulated rivers. It highlights the importance of fluvial processes to riparian vegetation and indicates that understanding the natural flow regime of a target river is a critical first step in the management of riparian vegetation and in the planning of riparian vegetation zone rehabilitation. Where the riparian zone is highly modified, through, for example, livestock grazing and/or weed invasion, natural regeneration of the riparian vegetation may be a long term process. If intervention, such as replanting, is appropriate, care should be taken that species selected are adapted to particular site conditions, such as flooding regime, landscape position and river geomorphology.

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32

Badman, Francis John. "A comparison of the effects of grazing and mining on vegetation of selected parts of northern South Australia". Title page, table of contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phb136.pdf.

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Abstract (sommario):

Accompanying CD-ROM inside back cover, includes Appendices. Bibliography: leaves 242-266. This thesis examines the effects on vegetation at selected sites in northern South Australia of excluding various herbivores over a four and a half year period and of two intense but controlled grazing pulses over a six month period followed by an 18 month recovery period in a dune-swale land system. These changes are compared with changes recorded over an 11-year period at the Olympic Dam mine site. It found that short-term changes in vegetation revealed by ordination of periodical cover, density and species richness, are attributable to the periodicity of rainfall and that, under present grazing regimes, rainfall effects override grazing effects. Differences between the effects of sheep and cattle hoof damage are worthy of further investigation, as is the impact of kangaroo grazing. These two factors may have important implications for the management of Australian rangelands. System requirements for accompanying CD-ROM: IBM compatible computer with Pentium processor or higher and Windows 95, 98 or NT ; 4 MB or RAM. Other software: Acrobat Adobe Reader.

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33

Oppermann, Alison. "Introduced plant invasion in small remnants of native vegetation /". Title page, contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09ENV/09envo62.pdf.

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34

Winnett, Richard G. "The housing circumstances and preferences of elderly Australian veterans and war-widow(er)s". Thesis, The University of Sydney, 1998. https://hdl.handle.net/2123/27564.

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Abstract (sommario):

This study set out to re—examine some of the assumptions behind Australia’s current housing policies. It is the first empirical Australian study which specifically addresses the housing circumstances and preferences of veterans and war-widow(er)s. Around 23% of Australian males and 7% of Australian females aged 65 or over are veterans or war-widows.

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35

Maddern, Guy J. "A review of cardiac surgery in South Australia /". Title page, contents and summary only, 1990. http://web4.library.adelaide.edu.au/theses/09MS/09msm1788.pdf.

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36

Black, Manu School of Biological Earth &amp Environmental Sciences UNSW. "A late quaternary palaeoenvironmental investigation of the fire, climate, human and vegetation nexus from the Sydney basin, Australia". Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2006. http://handle.unsw.edu.au/1959.4/25745.

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Abstract (sommario):

It is widely believed that Australian Aboriginals utilised fire to manage various landscapes however to what extent this impacted on Australia???s ecosystems remains uncertain. The late Pleistocene/Holocene fire history from three sites within the Sydney Basin, Gooches Swamp, Lake Baraba and Kings Waterhole, were compared with archaeological and palaeoclimatic data using a novel method of quantifying macroscopic charcoal, which is presented in this study. The palynology and other palaeoecological proxies were also investigated at the three sites. The Gooches Swamp fire record appeared to be most influenced by climate and there was an abrupt increase in fire activity from the mid-Holocene perhaps associated with the onset of modern El Ni??o dominated conditions. The Kings Waterhole site also displayed an abrupt increase in charcoal at this time however there was a marked decrease in charcoal from ~3 ka. Lake Baraba similarly had displayed low levels of charcoal in the late Holocene. At both Kings Waterhole and Lake Baraba archaeological evidence suggests intensified human activity in the late Holocene during this period of lower and less variable charcoal. It is hence likely that at these sites Aboriginal people controlled fire activity in the late Holocene perhaps in response to the increased risk of large intense fires under an ENSO-dominated climate. The fire history of the Sydney Basin varies temporally and spatially and therefore it is not possible to make generalisations about pre-historic fire regimes. It is also not possible to use ideas about Aboriginal fire regimes or pre-historic activity as a management objective. The study demonstrates that increased fire activity is related to climatic variation and this is likely to be of significance under various enhanced Greenhouse scenarios. There were no major changes in the composition of the flora at all sites throughout late Pleistocene/Holocene although there were some changes in the relative abundance of different taxa. It is suggested that the Sydney Sandstone flora, which surrounds the sites, is relatively resistant to environmental changes. Casuarinaceae was present at Lake Baraba during the Last Glacial Maximum and therefore the site may have acted as a potential refugium for more mesic communities. There was a notable decline in Casuarinaceae during the Holocene at Lake Baraba and Kings Waterhole, a trend that has been found at a number of sites from southeastern Australia.

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37

Schymanski, Stanislaus Josef. "Transpiration as the leak in the carbon factory : a model of self-optimising vegetation". University of Western Australia. School of Environmental Systems Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0095.

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38

Metwaly, Hassan Ali Hassan. "A study of groundwater contamination and bioremediation treatment using natural soil and vegetation". Thesis, University of Glasgow, 1999. http://theses.gla.ac.uk/2851/.

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Abstract (sommario):

This thesis is concerned with the following studies : 1- Ammonium analysis in soil and water including the determination of low levels of ammonium (<0.1 mg N/1) in groundwater and the colorimetric analysis of highly coloured groundwater samples. 2- An investigation of groundwater quality and soils at a contaminated industrial site. 3- Bioremediation treatment of the ammonium and nitrate contaminated groundwater using natural soil and vegetation and using soil incubation and pot experiments. These findings of a pot experiment suggest the possibility of applying the bioremediation treatment of the ammonium and nitrate contaminated water in the field. A field study should be undertaken to evaluate the efficiency of this bioremediation treatment. This field study would require a suitable uniform area to lay out the plots, preferably close to the source of water to be used. In addition, it is necessary to carry out a hydrological survey to determine the following aspects: 1-The size of groundwater reservoir. 2-The rate of removal of the water. 3-The time scale of the water application. The climatic conditions such as rainfall, potential evapotranspiration and temperature should be taken into consideration when carrying out the bioremediation treatment in the field as these climatic conditions affect the water requirements and the growth of grass. There are three options to apply the contaminated groundwater as follows : 1-To apply the contaminated groundwater at low or high volume depending on its level of nitrogen. 2-To blend well water with high level of nitrogen with well water with low level of nitrogen to achieve a realistic irrigation rate at a suitable nitrogen level. 3-To overirrigate in expectation that ammonium would be retained in the soil. The ryegrass used in this bioremediation treatment can be disposed of by incineration and landfilling the ash or landfilling the grass.

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39

Dehum, Salah Mustafa. "Spatial analysis and modelling of fire severity and vegetation recovery on and around Mt Cooke, south-western Australia". Thesis, Curtin University, 2015. http://hdl.handle.net/20.500.11937/1371.

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Abstract (sommario):

The South Western Australian Floristic Region (SWAFR) is an area with high biodiversity and species endemism. Numerous granite outcrops within the area provide specialised ecosystems for these endemic plants that are under threat by changes to the fire regime. This study reviews a fire on Mt Cooke in 2003. Using remote sensing and GIS, the fire is studied in relation to vegetation and fire indices to assess the fire severity and studies if the topography affected the fire severity. The vegetation recovery is monitored for ten years post-fire to assess recovery rates.

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40

Wise, Nathan History &amp Philosophy Faculty of Arts &amp Social Sciences UNSW. "A working man???s hell: working class men's experiences with work in the Australian imperial force during the Great War". Awarded by:University of New South Wales. School of History and Philosophy, 2007. http://handle.unsw.edu.au/1959.4/32462.

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Abstract (sommario):

Historical analyses of soldiers in the Australian Imperial Force (AIF) during the Great War have focused overwhelming on combat experiences and the environment of the trenches. By contrast, little consideration has been made of the non-combat experiences of these individuals, or of the time they spent behind the front lines. Far from military experiences revolving around combat and trench warfare, the letters, diaries, and memoirs of working class men suggest that daily life for the rank and file actually revolved around work, and in particular manual labour. Through a focus on working class men???s experiences in the AIF during the Great War, this dissertation seeks to discover more about these experiences with work in an attempt to understand the broader aspects of life in the military. In this environment of daily work, many working class men also came to approach military service as a job of work, and they carried over the mentalities of the civilian workplace into their daily life in the military. This dissertation thus seeks to understand how workplace cultures were transferred from civilian workplaces into the military. It explores working class men???s approaches towards daily work in two different theatres of war, Gallipoli and the Western Front, in order to highlight the significance of work within military life. Furthermore, it evaluates aspects of this workplace culture, such as relations with employers, the use of workplace skills, and the implementation of industrial relations methods, to understand the continuities between the lives of civilians and soldiers. Finally, this dissertation is not a military history: it adopts a culturalist approach towards the lives of people in the AIF, and in the environment of the Great War, in an effort to place the military experiences of these working class men within the context of their broader civilian lives.

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41

Bartošová, Pavlína. "Horský hotel s wellness centrem". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392146.

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Abstract (sommario):

The diploma thesis contain complete solution for Mountain hotel with wellness center including project documentation. The building is situated near area of Beskydy Mountains. Building plot is located in village Kunčice pod Ondřejníkem. The hotel consists of three parts: Wellness center, restaurant facilities, accommodation with recreational areas. The building has 4 floors and is non-celluar. The roof in the first floor is solved by vegetation roof, followed up with metal sloping roof . Construction structure is made of Porotherm ceramic blocks.

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42

Johnston, William Henry, University of Western Sydney, of Science Technology and Environment College e School of Environment and Agriculture. "The role of Eragrostis curvula (Schrad.) Nees. complex in temperate pastures in southeastern Australia". THESIS_CSTE_EAG_Johnston_W.xml, 2003. http://handle.uws.edu.au:8081/1959.7/29.

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Abstract (sommario):

This thesis examines the hypothesis that, in southern New South Wales and northeast Victoria, Australia, palatable taxa of E. curvula offer advantages that complement those of the species that are traditionally sown in temperate pastures in a landscape context.This hypothesis was based on a review of literature showing that, prior to European settlement, the vegetation, the landscape and the climate were broadly in balance, and the wateruse pattern of the vegetation of southeastern Australia resulted in water being used more-or-less completely by the end of summer. This maximised the capacity of the soil to take up and store water during autumn and winter.Three grazing experiments and one spaced-plant species evaluation study were used to assess the role of summer-growing, C4 Eragrostis curvula in pastures in the temperate zone of southeastern Australia.Issues relating to pasture production and the productivity of wool-growing sheep were investigated. Factors affecting the sustainability of the pastures and their potential on and off site impacts were emphasised.Modelling was used to explore issues of water use, arising from the grazing experiments. It is concluded that the persistence, production, water use patterns, and the adaptability of palatable varieties of E. curvula make it a useful and complementary addition to the range of species that are currently available for use as sown pastures in southern Australia.
Doctor of Philosophy (PhD)

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43

Rutherford, Jasmine Lee. "The role of geology, geomorphology, climate and vegetation, in controlling spatial and temporal changes in groundwater discharge from weathered crystalline basement aquifers in southwestern Australia". University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0006.

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Abstract (sommario):

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

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44

Kyška, Roman. "Penzion s restaurací". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-410041.

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The diploma thesis deals with the proposal of a new guesthouse with a restaurant. The building is located in a slightly sloping terrain in the cadastral area of the village Vlasatice Brno-venkov in the South Moravian Region in the Czech Republic. The ground-plan shape of the building is mostly rectangular with folded facade parts. It is a partially basement building, to a lesser extent, recessed below ground level with three above-ground floors. The pension has a total of 22 rooms with a total capacity of 46 persons for short-term accommodation. Four rooms on the first floor are designed as wheelchair accessible. For the proper operation of the pension there is a reception on the first floor and an office with the appropriate meeting room on the second floor. One-storey part of the building consists of a restaurant with a capacity of 76 persons, which is designed as a frame skeleton with intensive vegetation single-skin flat roof. The preparation and meals and service of the restaurant is ensured by the kitchen together with its operations and respective warehouses located on the first floor. The basement is used primarily for the operation of the guesthouse, which is located air-conditioning engine room, utility room, workshop or warehouse. The building is for the most part bricked and the peripheral, internal bearing or partition walls are made of polished ceramic blocks porotherm. External walls are insulated with contact insulation system ETICS of gray EPS polystyrene. The glazed Schüco façade is used as the shell of the skeleton structure. The construction of the ceiling is composed of filigree ceiling panels and a singlelayer flat roof with a slope of 3% is used for roofing the building. The thesis contains project documentation for the realization of the construction.

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45

Lopatin, Fourcade Javier [Verfasser], e S. [Akademischer Betreuer] Schmidtlein. "Unmanned Aerial Vehicles for Vegetation Mapping: Opportunities and Challenges / Javier Lopatin Fourcade ; Betreuer: S. Schmidtlein". Karlsruhe : KIT-Bibliothek, 2019. http://d-nb.info/1193126738/34.

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46

Alvarez, Barra Valentina [Verfasser]. "Holocene vegetation dynamics and disturbance regimes in north Patagonia Argentina (40°S) / Valentina Alvarez Barra". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1213974739/34.

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47

Loan, Lisien. "The response of native vegetation to rising groundwater and salinity levels in the upper south east of South Australia /". Title page, contents and abstract only, 1993. http://web4.library.adelaide.edu.au/theses/09AR/09arl795.pdf.

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48

au, j. anderson@murdoch edu, e Jonathan Anderson. "Impacts of Amending Bauxite Residue Sands with Residue Fines for the Establishment of Vegetation on Residue Disposal Areas". Murdoch University, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090831.155453.

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Long term storage of bauxite residue materials requires a capping stratum which will limit erosion while stabilizing slopes, limit deep infiltration of water into storage piles, and be aesthetically acceptable to the surrounding community. A diverse native vegetative community capable of surviving seasonal drought, low plant available water and nutrient constraints has the best potential of satisfying most, if not all of these requirements. Current and past rehabilitation of residue disposal areas (RDAs) using species native to southwest Western Australia has exhibited varying success. Current practices at Alcoa World Alumina Australias (Alcoa) Western Australia refineries have bauxite residue fines (< 150 ìm) stored within impoundments, in which the outer embankments are constructed with bauxite residue sands (> 150 ìm). The residue sands are also used as the growth media in the capping stratum for vegetation establishment on the disposal sites. Despite the inherently hostile properties of residue sand (pH > 10, EC(1:5) > 4 dS m-1, and ESP > 50), reductions in alkalinity (pH), salinity (EC) and sodicity (ESP) are corrected, through freshwater leaching, to a greater extent than is possible with residue fines. Although leaching can reduce the hostile character of residue sand, additions of phosphogypsum are typically added to expedite the removal of Na and alkalinity, and inorganic fertilizers are incorporated to improve the nutrient status of the growth media. However, due to the inconsistencies in vegetation establishment, which are attributed to poor water retention, inherent nutrient deficiencies and rapid loss of nutrients within residue sands (because of high hydraulic conductivity), further amendments are required. The aim of this study was to determine if amending the residue sand capping layer with residue fines would enhance its overall growth potential for vegetation establishment. Additions of fines to residue sands were predicted to increase water retention, add nutrients and increase the ability of the growth media to retain nutrients. Comparisons were made between the treated residue fines (seawater washed, carbonated, or unaltered) at a series of fines additions (1 - 20 % w/w) and a control(residue sand) amended with 2% (w/w) phosphogypsum and inorganic fertilizer. Comparisons were to determine the differences in 1) water retention, 2) nutrient concentrations and nutrient retention, and 3) plant growth responses and plant biomass nutrient concentrations between the growth media treatments. Four experiments were set up to measure differences in these variables which included: a glasshouse study involving the growth of Acacia saligna; a germination and emergence study (A.saligna); a two year field study in Western Australia; and a glasshouse column leaching study. Water retention increased with increasing percentage of residue fines addition. Plant available water (PAW) increased up to 110 %, with a 20 % increase in fines, representing an increase of 0.026 m3 PAW m-3 residue growth media, when compared to the residue sand only. This increase in PAW was attributed to changes in pore space distributions, due to the increasing fines contents altering the sandy texture to loamy sand texture class. However, initially much of this increase in PAW may not be realized, due to estimated temporary increases in osmotic potential associated with the high salt contents of residue sand and fines. Fines materials have much greater salt contents, and thus need to be leached to a greater extent than sands to remove the associated osmotic potential effects. Essential plant nutrients (P, K, S, Ca, Mg, and B) were increased with additions of residue fines in the glasshouse studies, although many nutrients (Mg, Zn, Mn and B) were still marginal for sustainable plant growth and development. Seawater treated residue fines additions produced the greatest increases in growth media nutrients with substantial increases in soluble (> 7 mg L-1) and exchangeable (> 0.10 cmolc kg-1) Mg, being up to 400 % greater than all other treatments. Along with these necessary nutrients, concentrations of Na were also increased in all fines additions treatments. Added Na may offset the benefits of fines additions, at least in the short term, due to inhibitions of cation uptake from Na competition. However, in the column leaching study soluble and exchangeable Na was lost rapidly from the profile, due to Ca and K displacement of Na from exchange sites during leaching. Soluble Na was removed from the profile to < 5 % of initial concentrations, after only three pore volumes of leaching, and exchangeable Na was removed from charge sites to less than 25 % of the initial concentration. Fines additions did increase concentrations of Mg and K on exchange sites, thus reflecting increased nutrient retention capacity relative to that in residue sand only. Plant growth responses and plant biomass nutrient concentrations were altered with the additions of residue fines to residue sands. The germination and emergence study demonstrated that the emergence of native seedlings was affected by additions of fines, due to the increased salinity and sodicity of the materials. Acacia saligna seedling emergence was inhibited by EC(1:5) > 2 dS m-1, which was highly correlated with a Na/Ca ratio of > 40, for all treatments, except the seawater fines additions. Seeds sown in seawater treatments emerged from growth media with EC(1:5) as high as 3.33 dS m-1 and appeared to be better correlated with Ca/Mg ratios than any other variable. Native vegetation growth responses showed mixed results in fines treated residues in the field. In the greenhouse study, plant growth tended to decrease with fines additions. Poor plant growth with increasing fines additions occurred despite the increased water retention and increased nutrients. This was attributed to the addition of Na associated with the residue fines, as increases in Na, EC and ESP in fines treatments all appear to have limited growth of Acacia saligna in the glasshouse over three months. Seawater fines additions had elevated Mg and B concentrations in plant biomass, and performed better than the carbonated or unaltered fines treatments, but still had reduced growth compared to the residue sand, which contained lower Na concentrations. Additional plant growth limitations may have occurred, due to possible plant nutrient deficiencies including: Mg, Zn, Mn and B and Na toxicity. Incorporation of residue fines into residue sands did increase water retention, nutrient concentrations and the nutrient retention capacity, but did not enhance the overall growth potential for vegetation, at least in the short term. Reductions in germination and emergence of seedlings and reduced plant growth were attributed to increases in Na concentrations introduced from the fines. Seawater washed residue fines had lower ESP and greater concentrations of nutrients, thus reducing the negative impacts from the additional Na introduced, and showed the greatest promise as a fines amendment. As leaching occurs over the first few initial months of rehabilitation, it is expected that the majority of the Na will be removed, from a system with an addition of 5 to 10 % fines, and the positive benefits of the fines additions will than be realized. Findings also illustrate that delaying the planting of vegetation on RDAs, until adequate leaching has occurred to reduce the Na concentrations, will substantially increase vegetation emergence and establishment.

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49

Fulcher, Helen Margaret. "A qualitative analysis of radio news in Australia". Title page, contents and abstract only, 1987. http://web4.library.adelaide.edu.au/theses/09ARM/09armf962.pdf.

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50

Widhyastuti, Ichsanna Samba Rukmie, e samba widhyastuti@gmail com. "Ethniehubs: A Case Study of Sydney, Australia". Faculty of Architecture, 2008. http://hdl.handle.net/2123/3957.

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Doctor of Philosophy
Abstract There has been a significant change in Australian consumer behaviour with an increase in time and money spent, in suburban ethnic business districts (named in this study as ethniehubs). But little attention has been paid to the role of ethnically owned stores in generating income within ethniehubs. In fact, there is still a lack of research conducted by architects and planners about the way in which the physical environment of ethnic stores in ethniehubs attract consumers, and the way in which the physical environment affect consumers’ behaviour. Therefore, the study is important in filling the current gap in literature. For this Sydney-based study, two separate ethniehubs are used for data collection - Leichhardt with a strong Italian character, and Cabramatta with identifiably Vietnamese attributes. The goal of this study is to find out how the ethniehubs have developed and how consumers behave in ethniehubs. The present study derived from architecture and planning, also addresses the effect of the physical environment of ethnic stores on consumers behaviour at both store and ethniehub level. The research has several questions to answer. How have Sydney’s ethniehubs developed? How do ethniehubs influence consumer behaviour? More specifically: What attracts consumers to ethniehubs? Who are these consumers? What do they purchase? Does the ethnic background of consumers influence their behaviour in ethniehubs? The data are collected through observation, survey and focus group discussions of consumers at both Leichhardt and Cabramatta. The findings of this research have a number of implications for urban planning, i.e tourism, place branding and place marketing. By understanding the importance of the physical environment of ethnic stores, more considered architectural design and interior decoration will ensure that their most highly valued aspects are reinforced. This study also contributes to the knowledge of urban planning of ethniehub shopping precincts and ethnic stores decorations each of which has important social and economic consequences.

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Tesi sul tema "Vegetation (S.E.Australia)"

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