Resource Management and Geography - Theses
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ItemAltitudinal distribution of vegetation in the headwaters of the Wongungarra River, Victoria( 1993)Changes in vegetation composition with respect to altitude were investigated in the sclerophyllous forests of the Australian mountain region. Vegetation was surveyed at 148 sites along two transects which were located to maximise variation in altitude and minimise the influence of environmental factors not directly related to altitude. The measurement, simulation, and estimation of environmental variables revealed that this aim was met except at the end-points of the transects where secondary influences are present.
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ItemEstablishment of grassland forbs in modified urban environments( 1998-04)The use of nature-like plantings to ameliorate degraded public landscapes in Europe and North America is extensive. There is a growing trend towards the use of ecological urban landscape design in Australia. Meadow landscape may have broad applications in the treatment of degraded landscapes in Australia. An examination of suitable establishment and management techniques for flowering grasslands was undertaken at Fawkner Memorial Park. This site contains large areas of severely disturbed and degraded soils, due to past burial practices. Trials on the establishment of forbs via direct seeding and plug planting were undertaken. The management of bulb species by mowing was examined through foliage removal treatments post anthesis. The management of grass biomass through herbicides was also examined. (For complete abstract open document)
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ItemThe interaction between the environment land use and hydrology of the Bogong High Plains area from 1850 to 1985( 1990)The Bogong High Plains form part of the' Australian alpine area which contributes significantly to the water resources of south-eastern Australia. The dual factors of a high average annual runoff and low levels of variability by Australian standards point to the value of the area for water production and the need for optimum management criteria. However, the hydrological response of the streams draining the alpine area to changing environmental and land use factors has not been previously addressed. In this thesis the environmental and land use history of the Bogong High Plains Area has been documented. On the basis of historical reports and photographs, management decisions affecting the Alps, and ecological studies in the Area since the 1940s, trends in the environmental condition of the Bogong High Plains Area between 1850 and 1985 have been ascertained. The land use history of the Area has been documented, including: the Aboriginal visits to the area to exploit the Bogong moth; the use of the subalpine and alpine environments by graziers and their stock: the impact of gold milling activities in the nineteenth and twentieth centuries; the frequency, cause and extent of fire in the region; the construction and management of the Kiewa Hydro-Electric Scheme; the operation of logging activities in the area; and the tourist use of the region for summer and winter recreation. An examination of the hydrological characteristics of the Bogong High Plains Area then followed. Twelve catchments were selected for analysis, ranging in size from 1.35 to 146 square kilometres, and in altitude from 634 to 1922 metres. Differences in the physical, geological, geomorphological and vegetation characteristics were related to the average annual water balances and hydrological variability. A review of the literature on the effects of fire, forestry, mining, tracks and roads, engineering works and grazing on runoff was made preparatory to an assessment of the effect of land use practices on the runoff characteristics of the twelve catchments. Standard hydrological techniques were used to assess the impact on streamflow of bushfire, insect attack, forestry operations, mining activity, road construction, construction works for the hydro scheme, and cattle grazing. Some of the results were unexpected. Although grazing was the land use of longest duration, the long-term trends in streamflow and inter-catchment comparisons based on differential grazing pressures only partially demonstrated grazing had a noticeable impact on runoff characteristics. The effect of fire, forestry, insect attack and mining activity also yielded indeterminate results. By contrast, the construction of roads and the development of the Kiewa Hydro-Electric Scheme resulted in statistically significant changes in streamflow characteristics, including runoff volumes, baseflow properties, and the magnitude of flood events. A model of the environmental history of the Bogong High Plains Area is proposed, incorporating trends in climate, fire frequency, vegetation cover, land use activity, and hydrological characteristics. From the model it is suggested that the occupation of the Bogong High Plains Area by Europeans since the 1850s has resulted in irreversible changes to the hydrological regime which predated the period of stream gauge operation and which could only be partially correlated with ecological trends. The model is used to ascertain the hydrological response of catchments to different combinations and intensities of grazing, fire and site disturbance, in association with present and alternative climatologically conditions.
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ItemLong-term landscape evolution: a case study from the lower Snowy River, Australia( 1994)The Snowy River which drains the south-eastern flank of the South-eastern Highlands of Australia, has frequently been taken as an example for various models of landscape evolution of the Highlands despite a paucity of primary field data on which to base an adequate description of the river's behaviour. In this study the lower part of the Snowy catchment has been investigated and, based on detailed fieldwork, a reconstruction of its morphological history since the late Eocene has been carried out. In so doing, it is demonstrated that detailed fieldwork provides the key to better the understanding of the Highlands' history. The Snowy River has experienced two phases of rapid incision since the late Eocene. Evidence of the first rapid incision is provided by karst caves formed in the phreatic condition which have not been modified by vadose waters, indicating rapid draining. In addition, fluvial sediments preserved as ridge-cappings indicate the Eocene course of the lower Snowy, as judged by their position relative to basalt of Eocene age. Further, below the Eocene river level there is another consistent level of gravel deposits. These former river levels suggest two stillstands of the Snowy River during its evolution since the Eocene. The modern fluvial system in the vertical plane, which is often overlooked in the literature, shows that many tributaries join the Snowy in the form of high waterfalls. Large knickpoints are features of the long profiles of both the tributaries and the master channel of the Snowy River, and provide further evidence showing the two phases of rapid incision of the Snowy River. The many lines of field evidence from this study show that i) the total incision of the lower Snowy over the last 40Ma is only two hundred meters, half the rate of downcutting previously inferred in the literature; ii) river incision proceeds in bedrock channels by knickpoint migration and the manner of this is different to that in alluvial channels; iii) two major knickpoints, each 100m high, have migrated headwards through the lower Snowy River, the first one resulted from a river course change soon after the late Eocene basalt flow while the second one can be attributed to sea level lowering in the Miocene; and hence iv) it is not necessary to propose tectonic uplift as an explanation of the landscape evolution of this area since the mid-Tertiary. Detailed field examination of this part of the South-eastern Highlands also shows that some of the assumptions underlying existing models for landscape evolution of the Highlands are not valid, such as tectonic uplift by Wellman (1979a & b; 1987), isostatic rebound by Stephenson and Lamberk (1985), and palaeoplain downwarping and scarp retreat by Ollier and Pain (1994). They have all based their models on over or up to 1000m of assumed post-Eocene (or even Miocene) uplift. In this study, it is demonstrated that the size, the diversity and the antiquity of the Eastern Highlands of Australia dictate that initial research into landscape evolution must concentrate first on collecting primary data from individual areas before a general model or models can be proposed.
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Item'It's in your hands': an assessment of the Australian Landcare movement( 1995)Australia's 'Landcare' program is a community-based, participatory program, established by Government, to tackle the problem of land degradation. It has been hailed by some, as the most imaginative sustainable development policy anywhere in the world. There have been many studies which have sought to measure the success of Landcare, using quantitative indicators such as the number of Landcare groups. This thesis seeks to devise alternative ways for Landcare to be assessed and thought about. It focuses upon the practice of Landcare in one particular region of Victoria: a practice which is formed out of the complex interaction of state policy, community aspirations and capabilities and the broader political and economic context. At a theoretical level, this thesis is informed by several areas of the academic literature. In particular, the role of the state apparatus in environmental management, the environment and political economy, and theories of ideology. These theoretical arguments are elaborated in several ways: through a detailed review of the emergence of Landcare as policy, both in Victoria and at a Federal level; through consideration of the complex bureaucratic arrangements which have grown around Landcare; and through a case study. The case study draws upon the experience of Landcare by farmers on the Dundas Tablelands in Victoria's Western District. Through participant observation and in-depth interviewing across seven Landcare groups, some insight is offered into the practice of Landcare in a local setting, for example: the ways in which government rhetoric about Landcare is enacted at the local level; the way in which the Landcare bureaucracy works with, or against, the program; and the way in which funding arrangements contribute to Landcare's effect on-the-ground. The case study draws upon the experience of Landcare by farmers on the Dundas Tablelands in Victoria's Western District. Through participant observation and in-depth interviewing across seven Landcare groups, some insight is offered into the practice of Landcare in a local setting, for example: the ways in which government rhetoric about Landcare is enacted at the local level; the way in which the Landcare bureaucracy works with, or against, the program; and the way in which funding arrangements contribute to Landcare's effect on-the-ground. It is argued that without an improved understanding of its limitations, the Landcare program is unlikely to succeed in the long-term. In the meantime, there are indications that calls for the expansion of Landcare may be to the detriment of the program’s original objective, which was to ensure more sustainable use of agricultural land in Australia. Renewed consideration is urged, of the ways in which Landcare's 'success' is measured.
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ItemRiver channel changes in Gippsland, Victoria( 1990)Channel changes during the period of European settlement on three streams in Gippsland, Victoria, the Thomson and Avon Rivers and Freestone Creek, were investigated on the basis of information contained in historical documentary sources including early maps and aerial photographs and the files and records of a number of Victorian government departments. Changes in channel position, planform characteristics, cross section, long profile and channel behaviour were analysed both qualitatively and quantitatively, revealing that river metamorphosis had occurred on parts of all three streams in the study area at different times during the period of European settlement. River metamorphosis in all cases involved changes in both channel morphology and channel behaviour; and on the Thomson River and Freestone Creek coincided with channel avulsion. A causal link between changes in the channel/floodplain relationship resulting from incision and river metamorphosis was identified. Incision associated with river metamorphosis was the result of both intrinsic geomorphological factors and human interference, the relative importance of which varied between streams. Changes in catchment-generated discharge regimes and sediment loads of sufficient magnitude to have caused river metamorphosis are considered unlikely except at the downstream end of the Avon River. Channel changes took place here in response to an increase in sediment load resulting from upstream channel changes and occurred in the absence of any major change in the channel/floodplain relationship. Since the explanation of the causes of river metamorphosis in terms of changes in the channel/floodplain relationship offered in this thesis cannot be accommodated by Schumm's (1969) widely accepted model, an alternative model of river metamorphosis is proposed. This model envisages channel morphology and behaviour as being controlled by an intrinsic sequence of channel and floodplain development, of which river metamorphosis is an inherent component. Extrinsic disturbances can cause river the intrinsic sequence and metamorphosis also even by short circuiting without this shortcircuiting. The occurrence of river metamorphosis in response to intrinsic controls and in the absence of changes in external inputs has serious implications for fluvial palaeohydrology. It means that climatic or other environmental changes cannot be validly inferred from alluvial evidence without independent supporting data.