Resource Management and Geography - Theses
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ItemTools for the conservation management of wildlife under uncertainty( 2001)This thesis explores the kinds of models that may be built to support environmental decisions when direct data are scarce and understanding of the ecology of a problem is incomplete. It explores empirically the effects of structural, parameter, shape and dependency uncertainty using explicit population models of a threatened Victorian species, the eastern barred bandicoot (Perameles gunnii) and the nationally endangered species trout cod (Maccullochella macquariensis). In particular, the thesis examines the sensitivity of management decision for these species to assumptions about dependencies, their implementation in standard computer programs, decisions about structural alternatives, assumptions about shapes of statistical distributions used to reflect uncertainties, and the choices of parameters values. The empirical exploration of these features in two different ecological, management, and data contexts sheds light on the ways in which models may be used effectively to support pragmatic management decisions for threatened species. One of the uses of population models is to assess the relative risks of extinction faced by a suite of species. The assessments are used to classify species into various categories of threat, and to create lists for management action. Such lists are used for state of the environment reporting, and to set priorities for protection and recovery actions. In many circumstances, there is insufficient time to develop explicit models. In their place, various expert or rule-based systems have been developed to assess conservation status. They use a suite of population attributes including population size, geographic extent, population subdivision, and rates of change in these attributes as surrogates for extinction risk. However, these systems have, until recently, ignored uncertainties inherent in the data used to make the classifications. This thesis also explores the theoretical underpinning of dealing with uncertainty in rule-based systems, so that they may better reflect the reliability with which assessments are made.
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ItemThe impact of kangaroo grazing on sediment and nutrient mobilisation( 2000-05)The adverse impacts on vegetation and soils due to livestock grazing have been extensively studied for many years. The extent to which native wildlife may also be causing change to their environment, as a result of local increases in population density, has been the subject of debate in a number of countries. In Australia there has been a growing awareness in recent years that native herbivores, particularly kangaroos and wallabies, may also be causing changes to ecosystem dynamics. Environmmental changes, produced firstly by the aboriginal people and then by Europeans, have favoured the larger macropods, resulting in increased population levels. These impacts can also be seen in areas around cities, where pressure from urbanisation has restricted populations to smaller and smaller patches of remnant vegetation and reserves, increasing the pressure on diminishing food resources within these patches. This study focuses on one of the areas that supplies drinking water to Melbourne, the Yan Yean Reservoir catchment, which is situated 37 km north east of Melbourne. This study adds to our understanding of the impacts of native wildlife populations by investigating the extent of some of these possible changes to ecosystem dynamics.
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ItemLost waters of West Moorabool: a history of a community and its catchment( 2004)Conflict around the allocation of the water resource cannot satisfactorily be reduced to a gradual decline of resource availability. This research explores the sources and mechanics of water conflict in a case study of the West Moorabool catchment, one recently designated as 'stressed'. Although situated in the temperate southeast zone of Australia, the loss of water from a predominantly rural catchment across a catchment divide to the urban centre of Ballarat has been a n1atter of continuing tension since the gold discoveries gave geographical definition to this part of European Victoria. As the demands for water increase, the political imperative to reappraise current water portioning gives full exposure to a conflict that, without historical investigation, could be oversimplified as a resource battle between urban recipients and rural donors. This history encapsulates the perspective of a changing rural community in a water supply catchment, by tracing the transition from a landscape of unallocated waters to one of overallocated water. The process whereby Ballarat water interests incrementally extended across the catchment had social consequences that polarised and entrenched the water conf1ict in this region. Although a homogeneous entity cannot be assumed, the rural community experienced a graduated decline in self-determination that has been more central to its water history than the loss of a physical resource. With water allocation being raised in many policy forums, there exists the potential to address a social agenda alongside assessments of resource capacity in a way that challenges the perpetuation of a traditional hierarchy of interests between rural communities and the inevitably more dominant and thirsty urban ones. A second but related dimension of 'loss' experienced by this catchment community concerns its increasing disconnection with the local waterways. Rivers, creeks, springs and reservoirs became less visible and accessible, flowing unseen behind reserve fences and closed roads. Relative to its more urban neighbour, the catchment community has, ironically, become physically dislocated from the water that has been of such defining significance from the first intrusion of Ballarat's powerful mining and municipal interests at Beales Swamp. An understanding of past linkages between a community and its waterways highlights the contemporary loss of connection and suggests a means of valuing 'water assets' for social and cultural meaning. Emphasis on water as a resource with volumetric attributes currently generates a negative culture around water, one that is not tempered by the creation and active management of a negotiated, watered landscape. For West Moorabool, the largely unquestioned expropriation of water from one catchment to supply another, the severance of waterways from many in the community, and the ongoing scientific investigations to reallocate a capped resource, combine to filter water of its social properties. This historical research infuses the politics of water with the memory and experience of one catchment community. It demonstrates a complexity that challenges the representation of water allocation as a problem of natural resource management with solutions more in hydrological modelling than agreed social outcomes.
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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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ItemAs if the landscape matters: the social space of 'farming styles' in the Loddon catchment of Victoria( 2001)Farming practice is spatially and culturally constructed. Fanners define ‘good’ farming through the social relations of everyday life, and through observation of landscape change. ‘Farming Styles’ is a sociological concept that aims to understand apparent homogeneity within diverse agricultural regions. Existing theoretical and methodological approaches to ‘farming styles’ have been unable to decide whether styles are ‘real’, and have struggled to provide an understanding of why and how styles emerge. This thesis re-conceptualises 'farming styles' as emerging from common patterns of responses by farmers to structural, cultural and physical influences. I agree that styles of farmer exist, but I reject the notion that farmers choose a particular style of farming (and the strategies and repertoire of practices that are associated with that style) because individual perceptions differ with respect to aspects of each style. Data were collected in a mail-out survey of farmers in the Loddon catchment with farms with a capital improved value over $50 000 and from all industries (n==366). To test the hypothesis that styles emerge from patterns of beliefs and behaviours, farmers were assigned to 10 groups by K-Means clustering. The clustering process was based on respondents’ answers to 31 belief/attitude statements about farming. Data on reported behaviours were also collected with respect to: participation in industry training; involvement in strategic natural resource management planning (Regional Conservation Strategy and Salinity Management Plans); Landcare membership; and adoption of conservation works, farm planning and quality assurance. Different groups (fanning styles) are found to have different average behaviours, and these are consistent with their beliefs about farming. To test the hypothesis that there is a relationship between the distribution of fanning styles and landscape type, five focus groups involving 32 farmers (9 women, 23 men) were convened to explore the importance of the landscape to farmers in 'reading' clues to farming practice. The focus groups revealed that clues to 'good' and 'bad' fanning are important in fanners' understandings of the landscapes around them and that landscapes themselves are mythologised. The focus groups also explored the way in which fanners differentiate and distinguish landscapes, aiming to produce an ethno-taxonomy of landscape types within the Loddon catchment. While mapping landscape types from the perspective of farmers was difficult due to the variability in individual perceptions of landscape difference, there was relative consensus at the larger' land system' scale. The relationship between the distribution of fanning style (10 styles) and landscape type (6 land systems) is found to be significant (x2 = 75.87, 45df, p=0.003). The relationship between the distribution of fanning styles and shopping towns (groceries) is also significant (x2 = 317.30, 252df, p=0.003), as it is for farm supplies shopping towns (x2 = 301.52, 243df, p=O.006). The results suggest that both the observation of farming practices within the landscape and the social interaction of farmers at locales such as shopping towns reinforce patterns of behaviour and belief about fanning. Thus, the continual exposure to sets of particular ways of thinking and doing farming within the local setting provides the context within which farmers perceive and adjust their own farming practice. However, the range and extent of each farmer's social networks and behavioural space will vary, and thus different farmers will be exposed to a different range of options and influences. Despite the diversity in approaches to farming, and the variability of individual's social networks and spatial behaviours, the landscape is important because it provides an underlying, recognisable and meaningful set of symbolic and material evidences of farming practice. The landscape enables a farmer to compare and contrast a range of farm practice options against a benchmark that each farmer knows intimately - his or her own land.
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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.