School of Geography - Theses

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The view from downstream: effect of Kenya's Tana River dams on flow character and its perception by local flood plain communities

Muthike, Joseph Muriithi ( 2000)

The damming of rivers has for a long time been associated with undesirable impacts on the hydrology of the downstream region (Goldsmith and Hildyard, 1984;McCully, 1996). This kind of impact is of particular concern when it affects the subsistence livelihoods of communities of the downstream region. In Kenya, 5 large dams were constructed in the country's largest river, the Tana River, between 1968 and 1988. The potential consequences of any major alteration of the downstream hydrology of this river are big, owing to the high dependence of the downstream tribal communities on the river regime. Concerns exist that the damming of the Tana River is responsible for deterioration of the resources naturally provided by the floodplain ecosystem (Emerton, 1996; Medley, 1994) but detailed research that demonstrates a clear link between the dams and harmful effect on the downstream hydrology is lacking. Some past environmental impact assessment and feasibility study reports on a number of projects on the Tana River have made inferences about the possible impact of flow regulation on the downstream hydrology (DHV, 1986a; Nippon Koei, 1996). There exist two gaps in the current understanding of the impact of Tana River dams on downstream flow. One is the clear demonstration of the actual nature of hydrological effects directly linked to the dams, two, is the lack of evidence that such changes are of a nature that has consequence to the subsistence activities of the downstream communities. In this study, the association of the dams with changes in downstream flow is investigated by combining analysis of flow data with evaluation of the local perception/observation of three tribal communities of the floodplain region. The assumption of evaluating the local observation of the river character by these communities is that the close dependence of their traditional subsistence systems on the river regime makes them sensitive to any changes in flow that are big enough to affect their subsistence livelihoods. Evaluation of the effect on downstream hydrology concentrates on floods and lowflows; and it is based on the pre and post-dams data record of a single river gauging station, due to serious problems discovered in the quality of data of other gauging stations of the floodplain region. The evaluation of the local perception/observation of river character change is based on a sample survey of 353 members of the Pokomo, Somali and Malakote ethnic groups and in-depth interviews with local key members of these communities. It is found that the Tana River dams have affected floods of the 900 to 1700 m3/s range only; but affected all ranges of lowflows. The perception/observation of change in the river hydrology is clear within the majority of local floodplain community members; a fact inferred to indicate significance of the hydrological effects on the traditional subsistence systems.
Alternative community states in reservoirs of the Central Highlands region

Bateson, Jane Karen ( 2001)

The occurrence of nuisance algae within reservoirs of the Central Highlands region is a problem facing Central Highlands Water and the communities they serve. Therefore, there is a need to know how to manage this threat. Management of the causal factors contributing to the development of algal blooms within the Central Highlands region, and Victoria as a whole, has tended to focus on reducing nutrient loads into the system. However, in shallow lakes nutrient control alone is often ineffective in managing the undesirable effects of eutrophication including algal blooms. The main reason for this is thought to be due to existence of alternative clear, macrophyte-dominated and turbid, phytoplankton-dominated stable states in shallow freshwater systems. This thesis presents analyses of two field studies carried out to investigate the alternative stable states hypothesis on shallow reservoirs of the Central Highlands region. First an assessment of spatial variation in chlorophyll a, macrophyte abundance and key growth regulating variables has shown that within reservoir spatial variation that is often assumed to be insignificant, is significant. Such spatial variation can lead to different conclusions being drawn regarding the application of ecological models and processes that may have caused observed patterns. Consequently, an appreciation of the effects of scale is vital to ensure ecological models, such as the theory of alternative stable states, are applied correctly and the outcomes of field experiments are not confounded by spatial variation. Second an investigation of shallow reservoirs of the Central Highlands region revealed that the presence of macrophytes is associated with low algal biomass. Parallels were drawn between study sites and the model of phase changes of shallow lakes undergoing eutrophication (Moss et al., 1996). A majority of reservoirs were characterised as potentially being within the clear, macrophyte-dominated alternative state, either in the unique clear Phase I or transitional Phase n. However, several reservoirs of the Central Highlands region did not bear a resemblance to any of the alternative states (phases) identified in the literature. Accordingly, it can be concluded that reservoirs of the Central Highlands region may support alternative states but that phase changes used to describe communities of the Northern Hemisphere lakes need to be modified to suit Australian conditions. This study emphasises the need to adopt a holistic approach to managing the undesirable effect of eutrophication such as algal blooms. Within the Central Highlands region a holistic approach should include management of the macrophyte communities, water level manipulation and potentially biomanipulation in addition to nutrient control.
My land, our river: private property rights, public goods and land use decision-making in the riparian zone

Terrill, Daniel I. ( 2001)

Ever since public choice theory began to emerge earlier this century, by applying the methodology of economics to the study of politics, it has been fascinated with the perceived conflict between private property rights and the public or the common good. A large component of the environmental movement, by adopting the public good as its unspoken goal, has necessarily found itself at the heart of this private versus public good debate. There have been many studies into the applicability of these public choice theories to real world environmental problems. Some of these have gone to the micro level and tested the assumptions of these theories with actual attitudes and motivations of the individual. At another level there have been studies into the impacts of state environmental policy, normally assessed from the macro level of the overall environmental change resulting from a policy. This thesis draws these two distinct bodies of research together. It recognises that the mentality of social choice theory has long been firmly entrenched in Australian state environmental policy. It also recognises that, as a result of being based upon theories that are not universally applicable to all situations, certain environmental policies fail because they do not elicit the desired behaviour from the individual. It goes on to demonstrate that the failure of certain policies can be attributed to the attitudes and motivations of the very people whose behaviour the policy aims to change, the behaviour of the private property owner. The riparian zone, typically defining a boundary between private and public property, is at the heart of this private versus public good debate. In this zone the activities of the private land manager can have significant public implications, in forms as diverse as water pollution, loss of biodiversity, and regional soil degradation. Yet the relationship is not all one directional, for the riparian zone is also an area where public policy often impacts upon the private property owner. Environmental decline of riverine and riparian environments has led inexorably to pressure for more and more controls on private land use to preserve a number of `public good' environmental values such as water quality, biodiversity and regional soil productivity. A range of planning regulations, specific to floodplain environments, also restrict the rights of the private property holder, once again in the name of the public good. On a regulated river system the relationship is even more problematic, because the manner in which the river is regulated by the public authority can have massive impacts on the riparian landowner. Floods on Australia's Murray River in October 1996, the result of the partial draining of Lake Hume, bear testimony to this. This thesis begins with a discussion of the power of the riparian landholder to influence environmental quality, by reviewing the ways in which terrestrial and aquatic conditions can be influenced for the better or worse by certain riparian land use activities such as stock grazing and fencing. Having outlined the ecological importance of the land use decisions made by riparian landholders, the existing influences upon the riparian farmers' land use decision-making are then identified, examining riparian farmers along Australia's Upper Murray River as a case study. Through surveys, in-depth interviewing, and participant observation, it explores influences on farmer land use decision-making. It discovers why farmers make the land use decisions they do, and it exposes the true impact of state policy on these decisions. A river-based riparian zone assessment was also conducted along each farmer's property, enabling observation of how the attitudes and views displayed in the surveys and interviews translated into different riparian land use activities. The results have revealed a number of opportunities and constraints to obtaining landowner co-operation in stream frontage management, many of which have significant implications for the management of river frontages throughout Australia. This thesis concludes by defining the nature of the problems present in the riparian zone, and the extent to which they can be explained by existing theories.
In the wake of June 4 : an analysis of the Chinese students' decision-making process to stay in Australia

Gao, Jia ( 2001)

This is a study of the Chinese students' efforts to gain the right and chance to stay on in Australia after the June 4 massacre event occurred in Beijing in 1989, when there were about 20,000 of them living in Australia. The specific focus of this study is the experiences of the students over a period of twelve months from 4 June 1989 to 27 June 1990, when the students were virtually allowed to stay permanently. This was a special onshore migration intake. Such an intake once had a significant impact upon Australian humanitarian and refugee immigration policies in the late 1980s and the early 1990s. This is a topic relevant to international and refugee migration and in need of empirical explication and theoretical conceptualisation. A comprehensive study of the decision-making experiences of both international and refugee migrants has many dimensions. To develop an adequate portrayal of the onshore asylum seekers' decision-making process, this study uses the multimethod approach. Information gained from in-depth interviews forms the main empirical basis of this study. The data collected through participant observations is woven in among documentary sources, and both provide context to the main interview-based data. In the course of the literature review, current thinking on identity, especially on strategic identity formation is found to be a most useful theoretical framework to guide this study. By utilising the identity formation framework, this study addresses five aspects of the Chinese students' efforts to form their onshore asylum seekers' identity and to meet the Australian government's migration criteria for gaining the right and chance to stay on in this country permanently. The main features of the onshore asylum seekers' efforts to shape their identity to suit government criteria can be summarised as follows. Firstly, as these asylum seekers are onshore, they necessarily have extensive involvement with the local agencies in dealing with their residence issue. This involvement offers asylum seekers various notions of what a 'refugee identity' is, and this in turn influences how they constitute themselves in this local context. Secondly, the efforts of the onshore asylum seekers are made away from home in a new place. As such, they make their decisions in a newly formed primary social group, instead of within a family which, in current studies, is the most commonly documented decision-making unit. Thus, their decision-making distinguishes itself from the family-based process in many ways. Further, as onshore asylum seekers are not recognised by nor rescued by refugee agencies, they have to provide solid evidence to prove that they fit in with refugee criteria and are qualified to stay. This expectation results in onshore asylum seekers participating in a very self-conscious and more strategic process of constructing a refugee identity. Furthermore, the onshore refugee identity is consolidated and expressed by interactions with the major local agencies. This influences these agencies in terms of the way in which the onshore asylum seeker issue is perceived and solved. In particular, the asylum seekers actively contacted and lobbied the government, the media and the migrant service organisations. Lastly, as a logical development of the onshore asylum seekers' efforts to stay, the seekers take highly organised political actions, which often comply with the main themes of the conflicts in international political ideology.
What is the value of a hole in the ground?: What is the value of discrete choice contingent valuation?

Cook, Darron Manuel ( 2001)

The inability of market price systems to reflect the social value associated with environmental conservation presents a barrier to the achievement of overall allocative efficiency. Stated preference valuation techniques such as the contingent valuation method have been found to be useful in capturing and measuring unexpressed preferences for environmental protection and enhancement. When applied correctly, these techniques can alleviate some of the most intractable market failures, such as those which involve pure public goods. This thesis explores the theoretical validity of different approaches to contingent valuation questioning through a survey of Victorian households' attitudes to the dereliction of open gold mine pits in the Victorian countryside. The methodological research involves comparison of discrete and continuous models of contingent valuation questioning, including a wide scale test of a new approach to discrete questioning, referred to as the "dissonance minimising choice" method, which seeks to correct the upward bias of yea-saying suspected in dichotomous choice studies. The results reveal a notable level of community concern about present mining practices in Victoria and a considerable willingness to pay for minesite rehabilitation. The results for the contingent valuation method indicate that survey respondents made robust and rational utility-maximimsing choices. The discrete-choice results were still significantly higher than the results for open ended study, with the performance of the dissonance mimimising choice method rather mixed in comparison with the traditional dichotomous choice approach. i
Spatial variation in benthic community structure in upland streams: the influence of fine sediment transport

Bond, Nicholas R. ( 2000)

Physical factors can play an important role in structuring plant and animal communities. Together with spatial variation in their magnitude, differences in species tolerances to these factors are thought to explain considerable variation in the structure of natural assemblages. This thesis examines spatial variation in fine sediment transport in upland streams, and the effects of this on the structure of benthic invertebrate assemblages in this system. I initially surveyed sediment transport rates (3 times) using box type bedload traps and the faunal assemblages (twice) on individual stones at 12 sites on 3 regulated and 3 unregulated streams in the upper reaches of the Acheron and Yarra catchments, which drain from the Great Dividing Range, southeastern Australia. This study region spans a geologic boundary, and includes areas of acid volcanics in the north, and granite and sandstone to the south. Sediment transport rates, which were measured only at low flow ranged from 5+2 to 821+115 g.day' (mean f 1 SE) at each site. Transport rates between the volcanic and granitic/sandstone catchments accounted for most of the variation between sites, and thus differences in transport rates between the two geologies approached 3 orders of magnitude. The flow diversion weirs on some of the streams were found to negate any differences in sediment transport rates between the two catchment types. Multivariate analysis of macroinvertebrate assemblages clearly distinguished between assemblages from sites in the volcanic and granitic areas. Overlaid on these differences was the effect of flow regulation, in which assemblages at regulated sites in both catchments converged toward one another in terms of overall assemblage structure. The composition of the assemblages at these regulated sites differed from unregulated sites in both catchment types. Notably, although multivariate techniques clearly established the above patterns of difference, commonly measured variables such as species richness, total abundance and the abundance of common taxa showed ambiguous patterns with respect to catchment geology. The multivariate analyses suggest that differences in community structure between granitic and volcanic streams are partly related to the effects of sediment transport. However, I was not able to demonstrate this to be the case. In a field experiment in which sediment transport was excluded across individual patches of the streambed at 6 of the unregulated study sites, no changes were observed in the fauna colonising these patches relative to controls in which sediment transport was maintained at natural levels. This was so in both the volcanic and granite catchments. Nevertheless, multivariate analyses again showed assemblages within the granite and volcanic catchments to differ in a similar fashion as observed in the original survey. In a set of artificial stream channels located adjacent to one of the study streams, changes in the benthic community were monitored in response to short-term and long-term sediment addition. These two experiments considered changes in sediment loads that might occur, in the short term as a result of small spates (a pulse disturbance), and in the long-term as a result of natural variation in sediment loads, or alternatively as a result of human impacts (a press disturbance). In both cases sediment addition caused only minor, but consistent changes in the benthic assemblage. In the case of disturbance caused by spates, it appears that changes in flow are the predominant mechanism disturbing the community during these events. Overall, these communities appear to be resistant to the effects of sediment transport. Presumably this resistance relies on the maintenance of suitable habitat, and thus sedimentation of rocky substrates would probably cause far greater changes than were detected here in response to sediment transport. It is possible that in the granite streams surveyed, the effects of sediment transport are to some degree mediated by the ability of animals to find refuge from sediment induced abrasion, perhaps by seeking shelter on the lee side of rocks, or in dead water zones where scour by sediment transport is minimised. Future research must concentrate on the physiological tolerance to sediment transport of these organisms, and whether behavioural adaptations allow stress to be minimised in heterogeneous stream reaches.
Spatial modelling of landscape-level vegetation dynamics, Mont Do, New Caledonia

Perry, George L. W ( 2000)

The feedbacks between landscape pattern and the processes operating in the landscape are central to the emerging discipline of landscape ecology. In this thesis a spatially explicit model is used to explore the landscape-level dynamics of a forest-shrubland complex on Mont Do, New Caledonia. In particular, it seeks to understand the dynamics of an unusual intermediate plant assemblage comprising a scattered emergent layer of coniferous trees (Araucaria laubenfelsii) over maquis (shrubland); this conifer is also present as an emergent tree in the adjacent, closed rain forest. The vegetation on Mont Do forms a spatially complex mosaic of maquis, maquis with emergent Araucaria laubenfelsii, Araucaria woodland, and rain forest (both with and without A. laubenfelsii). The density of A. laubenfelsii across the landscape is highly variable, from areas of maquis where the species is absent, to areas where stem densities are very high. In many places the boundary between rain forest patches and the maquis is extremely abrupt. These structural assemblages form interesting spatial patterns at the landscape level, possibly reflecting the history of disturbance. The landscape model developed in this thesis simulates the processes of vegetation succession and fire spread in a spatially explicit manner. Vegetation succession is simulated using a spatially implemented state and transition approach incorporating the spatially explicit dispersal of seed. Fire spread is modelled using a spatial percolation algorithm. Sensitivity and uncertainty analyses suggest that the model is most sensitive to parameters related to fire spread. However, this is probably an artefact of the design of the fire spread algorithm rather than an ecological effect. The model also exhibits some sensitivity to certain ecological parameters such as maximum seed dispersal distances and the length of time spent in some, but not all, of the vegetation classes. Spatial uncertainty analyses demonstrated that the model is sensitive neither to changes in the initial spatial conditions (topography and vegetation) nor to small misclassifications in this data. Analysis of the landscape model suggests that infrequent large fire events are primarily responsible for driving landscape dynamics. The current landscape pattern forms a complex mosaic of maquis and forest patches. However, prior to human colonisation of New Caledonia the Mont Do landscape was probably forest-dominated. Model results show that under altered fire regimes the landscape may rapidly `switch' from being forest-dominated to being a maquis-forest mosaic. After an initial large fire triggers such a switch, positive feedback loops operating at several spatial scales act to reinforce this change by increasing the average size of fire events and hence increasing the flammability of the landscape as a whole. It is suggested that alterations to the spatio-temporal correlatory structure of the fire regime may be as important as simple increases in fire size. The current abundance of the unusual intermediate vegetation types is probably attributable to higher disturbance frequencies over the last 200 years. As a result of recent changes to the fire regime on Mont Do, it is possible that the current landscape structure is not stable, and is instead, transient. The heavy recruitment of A. laubenfelsii into the maquis from forest patches suggests a move towards a more heavily forested landscape composition. Model results suggest that the landscape may be at a point from which it could move to either a maquis-dominated condition (especially if a series of fire events occur in the next 100-200 years), or, in the absence of disturbance, could move towards a forest-dominated condition. External forcing processes such as global climate change and its effects on the fire regime are explored, and it is suggested that they may also exert a significant impact on the landscape structure. Environmental changes, human-induced or not, will continue to affect the landscape through their influence on the fire regime. However, although the persistence of the unusual intermediate assemblages in the landscape seem uncertain, it is unlikely that Araucaria laubenfelsii will completely disappear from the landscape, although it's abundance may become further restricted.
If Descartes swam with dolphins: the framing and consumption of marine animals in contemporary Australian tourism

Jarvis, Christina Harwood ( 2000)

Cultural geography has become increasingly interested in the ways in which nature is socially constructed within society as other. In more closely examining the broad category of 'nature', the field of animal geography has come about in an attempt to rethink the place of animals in society. The Cartesian culture/nature binary is seen to be one reason for the mistreatment of animals in society. The thesis investigates to what extent the binary is challenged or reinforced through the act of visiting animals within an ecotourism context. To this end the thesis looks at the ways in which marine animals are produced for and consumed by the tourism industry in Australia. Set within a backdrop of the early collection and display of marine animals as a form of imperial expansion, the thesis travels across a spectrum of marine animal tourism experience, from a point of extreme mediation to one of minimum mediation. In investigating the ways in which marine animals are framed and toured in contemporary Australia, the thesis utilises two key case studies, the Penguin Parade on Phillip Island in Victoria, Australia and Wild Dolphin Tours in Port Phillip Bay in Victoria, Australia. At the same time, the case studies act to uncover a key question of the thesis, namely the reasons why people choose to visit marine animals in Australia. Initially the thesis investigates the display of marine animals in early aquaria, modem day theme parks and in Blue Zoos. In then moving on to the first case study, the thesis considers the ways in which penguins are framed as a novelty event, as a threatened animal and as a link 'to the wild' for tourists. Data collection through a visitor survey and participant observation showed that tourists visit the birds as part of a more general family/friends holiday experience. The second case study begins with an examination of the ways in which dolphins are framed through popular culture as at once human like and as better than humans. A visitor survey and participant observation undertaken with tourists who went to sightsee and swim with the bottlenose dolphins of Port Phillip Bay revealed that visitors primarily chose to visit these animals because of a desire to see them unconfined and to learn about them. The thesis found that marine animals are framed for tourism in Australia in a multitude of ways which simultaneously bring the animals closer to humans and set them apart. Environmental education differed between the case studies. Generally tourists felt they learnt about the animals through a combination of seeing them first hand and experiencing some form of interpretation. Overall the culture/nature binary was found to be actively supported but also challenged by the practice of ecomarine tourism examined in the thesis.
Data and information exchange in multi-jurisdictional river basins : an evaluation of procedures

Chenoweth, Jonathan Lee ( 2000)

The exact role that data and information exchange plays in the management of multi- jurisdictional river basins needs clarification if management processes are to be improved. With many major river basins being shared by several countries, and competition for water resources becoming increasingly severe, it is important that mechanisms are established to permit the comprehensive integrated management of shared basins. Under international law nations have a clear obligation to co-operate in the management of multi-jurisdictional river basins, including in the area of data and information exchange. Mechanisms for doing this, however, are not well developed. The Murray-Darling River basin in south-eastern Australia and the Mekong River basin in south-east Asia are both major multi-jurisdictional river basins in which inter-government authorities for managing the river basins have been established with similar aims and legal foundations. Despite the significant differences in the socio-economic and political environments of the two basins, both the Murray-Darling Basin Commission (MDBC) and Mekong River Commission (MRC) have set up data collection networks and exchange mechanisms which function through quite similar means. The efficiency of the networks, however, differ markedly for a variety of reasons. The MDBC also engages in significant data and information exchange with its basin community as part of its extensive efforts at working with the community. This is integral to its management objectives for the basin. By contrast, the MRC's efforts at working with and communicating with its basin community have been limited to date. Existing community participation and communication mechanisms adopted by other organisations within the basin indicate the types of processes the MRC itself could adopt as it develops. The exchange of high quality data and information at the highest decision making level can help balance political based decision making with technical considerations. The internal working documents and meeting minutes of the MDBC and MRC reveal that the MDBC draws to a significant extent on the data and information channels it has developed to support its decision making processes. The MRC, however, has yet to make extensive use of its databases and other information sources, due to its developmental stage as an organisation. Several significant planned initiatives mean that it will depend extensively on the data and information systems it has put in place if these initiatives are implemented. Tough decisions, however, depend upon sufficiently reliable data, meaning that some improvements are required to the data and information systems the MRC has in place for supporting its decision making. This research shows that effective data and information exchange between all significant players in a multi-jurisdictional river basin is indispensable to achieving the integrated management of such river basins. The effective and sustainable management of multi- jurisdictional river basins depends upon sound functional data and information systems, with co-operative efforts being built upon this. Not only is data and information exchange between all significant players needed to implement integrated management itself, this research suggests that data and information exchange also plays a major role in developing the impetus for integrated management amongst those with political power in a multi-jurisdictional river basin.
Urban road traffic noise and health

Roberts, Michael John ( 2000)

Some people say they are annoyed by traffic noise. There is rather a lot of evidence to show that where traffic noise is louder, more people say they are annoyed by it. On the basis of this sort of evidence, there is a consensus that road traffic noise causes annoyance. Traffic noise is also suspected of being dangerous to health: of making people ill; so ill they reach for painkillers or even visit a doctor to get medicine prescribed. The fundamental aim of this thesis is to find out whether this is happening in Melbourne. The available evidence contains anomalies: people seem to be healthy where noise is loudest. Even annoyance studies sometimes detect unexplained peaks of annoyance in quieter places; or a plateau of annoyance in high noise. However, the anomalies display a certain consistency. Traffic noise is orthodoxly measured by loudness. Several studies have found a peak of annoyance at around 60 decibels. The consistency of the anomalies suggests that some other physical characteristic of noise may be responsible for the anomalous responses. This thesis sets out to explore the urban soundscape in an attempt to find such a characteristic, and discovers the pattern of alternation of passby noise and background sound: passby patterns. The orthodox loudness measure is essentially a proxy for the daily average sound energy delivered to the ear by traffic. To define patterns requires taking this measure apart - splitting traffic noise into two sounds: the sound of passbys and the background sound. The definition builds up through the use of point source theory, observations in urban and rural environments, experiments with a typical sedan in isolated locations, and experimentation with techniques for the measurement of background sound generated by roads. The tools applied are ears, stopwatch and sound meter. The result is a set of techniques aimed to measure patterns of passby noise in urban environments. Application of these techniques at 102 randomly selected sites spread over 150km2 of urban environments detects passby patterns in Melbourne. By way of an example, the final stage of this investigation embeds pattern measurements within a small, orthodox study of the annoyance and health responses to traffic noise measured by decibels. The results are consistent with regular or rapidly alternating passby patterns being closely associated with annoyance and ill health. In particular, in relation to people who are sensitive to noise, it should no longer be assumed that peak distress at approximately 60dB(A) is anomalous. It may well be due to high levels of patterning of passby noise. The result requires confirmation, to be sure, but the evidence is sufficiently strong to suggest that traffic noise and patterns of passby noise, or something closely associated with them, are probably associated with health problems in Melbourne.

School of Geography - Theses

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