Office for Environmental Programs - Theses
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ItemDoes a state-and-transition model designed focused on vegetation in temperate eucalypt woodlands represent bird communities?( 2022)Temperate eucalypt woodlands have declined across southern Australia due to agricultural expansion. A state-and-transition model (STM) has been developed to aid in the restoration of Grey Box (Eucalyptus microcarpa) woodlands in the Goulburn Broken Catchment Management Authority (GBCMA). This STM has been developed based on vegetation, the aim of this study was to explore whether it could also be applied to bird communities. For an STM to adequately represent fauna it must be based on the vegetation characteristics that are functionally important to the species of interest. Along with vegetation, predatory and competitive interactions between species are important in shaping faunal communities. In the case of birds in this environment the overabundant aggressive bird species, the noisy miner (Manorina melanocephala) is known to contribute to shaping bird communities. The relationship between bird diversity and species composition, with state was analysed. The effect of noisy miners and vegetation characteristics on bird communities were explored. The results suggest that while bird diversity (overall abundance and species richness) showed little difference between sites, species composition varies. This highlights the need to set clear management objectives and shows potential of the STM to predict how at-risk groups of species may respond to management actions. The results are consistent with the literature on the negative effect of noisy miners on bird abundance, especially small woodland specialist birds. Medium shrubs and trees with a diameter at breast height < 40cm positively affected overall bird abundance and negatively affected noisy miner abundance and therefore could be used to improve state definitions so that they better represent birds.
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ItemCulturally and linguistically diverse communities and bushfire preparedness in Victoria, Australia: The experiences and perspectives of government and agency staff( 2022)People from culturally and linguistically diverse (CALD) communities are often identified as being more vulnerable to natural hazards due to a range of social, cultural, economic, and linguistic factors. In turn, with Australia’s population being increasingly characterised by cultural diversity there has been growing recognition of the importance of the inclusion and participation of CALD communities in bushfire planning and preparedness, to both reduce vulnerability and support resilience. Despite this, there exists a significant gap in the literature pertaining to the experiences and perspectives of government and agency staff in strengthening the resilience of CALD communities in this area, resulting in little published insight into the factors that shape the consideration and inclusion of CALD communities in bushfire preparedness and response. To improve understanding in this area, seven in-depth, semi-structured interviews were undertaken with Victorian government and agency staff who have a role or experience in engaging and working with CALD communities. Additionally, a document analysis was undertaken of key strategic plans and policy documents. Through the reflexive thematic analysis of the interview and document data, four key themes were identified. These included the consideration of the inclusion of CALD communities in emergency management documents, understanding and defining the concept of community, challenges to and needs for engaging with CALD communities, and reflections on successful engagement with CALD communities. These themes in turn provided important insights into the value of intersectionality for understanding CALD communities, the needs and opportunities available in capacity building and investing in preparedness, and the role of social capital in developing relationships with CALD communities.
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ItemReviewing structural and functional indicators in aquatic ecosystem management programmes( 2022)Ecosystem function is a foundational part of ecosystem health, but it is often neglected in the practice of ecosystem management. Utilising a systematic literature review, this thesis conducted a state-of-evidence review, analysing sixty (n = 60) grey literature documents across multiple countries and organisations to understand the prevalence of function in measures and conceptions of ecosystem health. Only 28% (n = 13) of analysed documents included definitions of waterway health that included function, and only 30% (n = 18) integrated function into their conceptions of waterway health. More generally, this thesis observed noticeable deviation in analysed documents from management best practices advocated for by contemporary ecosystem science – including occluded rationales, vague language, and imprecise metrics for assessing waterway health – and discusses these findings with a narrative-style review of similar trends in the broader ecosystem management context. These results support previous observations of a strong structural bias in current ecosystem health monitoring regimes and suggest the need for closer examinations into the processes and rationales by which such an important factor could be ignored in current monitoring regimens.
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ItemThe Effect of Artificial Light at Night on the Ecological Soundscape: A Community Level Response( 2022)Artificial light at night (ALAN) is widespread, unprecedented and continues to expand rapidly due to increasing urbanisation. The biological effects of ALAN on natural systems and individuals have been uncovered over the last two decades, yet the impacts on ecological communities (interconnected groups of populations occupying the same area) have remained largely unexplored. In this study, I assessed the effect of ALAN on the ecological soundscape (the combination of sounds which define the environment) of different communities across an urban-rural gradient. I deployed bioacoustic recorders across six sites of differing levels of light pollution and urbanisation for two weeks, from sunrise to sunset, to analyse the variation of species diversity and acoustic complexity using established bioacoustic indices (Acoustic Complexity Index (a measure of species diversity), Root Mean Squared (as proxy for anthropogenic noise) and Acoustic Entropy (the complexity of sounds in an environment). Accounting for abiotic factors such as weather and anthropogenic noise, I found that natural variation in moonlight and light cues of key daily transitions were masked by artificial light, affecting species diversity and acoustic complexity in sites with greater urbanisation. Temperature was positively correlated, and windspeed and traffic noise were negatively correlated to species diversity. Both abiotic factors and masking can result in decreased fitness of individuals, altered trophic interactions and disrupted predator-prey mechanisms. Additionally, urban communities demonstrated stable levels of acoustic entropy despite species diversity decreasing, consistent with temporal niche partitioning (the coevolution of activities at differing times amongst species in a community to decrease competition). Understanding the mechanisms behind the impact of ALAN on ecological communities can assist in limiting the impact of anthropogenic pressures on the environment.
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Item(Em)Powering a Region and Shifting Coal-tures: Alternative Frameworks for a Just Energy Transition in the Latrobe Valley( 2022)What role do identity and emotion play in energy transitions? Not commonly considered in techno-economic metanarratives on energy transitions, emotional geographers and feminist scholars illuminate the need to consider the localised, socio-emotional relations of communities facing decarbonisation. Literature in this space reveals how extractive industries represent as ‘masculine, rational, economic, emotionless’ sites. Operating to conceal non-hegemonic gender identities and particular emotions as they are relegated to feminine subjectivities. In seeking out alternative frameworks beyond the existing energy paradigm for a just transition, this research poses the questions: How are identity and emotion present in news media on mining transitions in the Latrobe Valley, and what are the implications of these discursive framings for transition futures? Guided by a conceptual framework founded in critical feminist theory, this thesis contributes to the emergent field of gender and energy transitions, distinguished by the joint application of intersectional theory and a politics of emotion. I explore these questions through a thematic analysis of eighteen newspaper articles, published about the case study region of the Latrobe Valley between 2014 and 2022. This research interrogates the central and supporting identities in news media, and the material implications of these discursive framings for transition futures. The analysis further examines the emotional recollections of these subjects, conceptualising the role of affective subjectivities in (re)constructing community identity, and (re)imagining a collective post-carbon future. The findings reveal representations of identity in news media reflect normative gender stereotypes, privileging masculine identities in transition futures, whilst identities of social differences and affective recollections are supressed or omitted entirely. Contributing to the nascent body of scholarship on extractive landscapes as gendered, emotional geographies, this study presents the need for energy transitions in the Latrobe Valley to be considered as socio-material-emotional processes. Highlighting how exclusion of these tenets in news media work to shape meaning-making of transitions.
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ItemWhat is the impact of glitter, as a type of microplastics, on springtail, Folsomia candida?( 2022)With the rapid development of urbanization, plastics are continuously produced in the industry, and large amount of them are released to the environment. When plastics released to the environment, they could be degraded by physical, chemical, or biological approaches to form microplastics. Microplastics, the mixed plastics with size smaller than 5 mm, have raised more concern than before as an emerging contaminant that can affect the environment and ecosystem. Furthermore, microplastics have high variety on their size, shape, and polymer type, which increase the difficulty to measure their toxicity and quantify them in natural environments. Glitter, a primary source of microplastics, is usually used in cloth and cosmetic, which normal structure include a polymer coating, a colored aluminum coating, and core PET film. Glitter may directly release to the environments because there is no regulation on the recycle of glitter, and thus many researchers urged to promote biodegradable glitter, a plant-based glitter, as an alternatives to replace conventional PET glitter. However, there may have already large amounts of PET glitter released to the environment, but previous studies on microplastic analysis usually ignored resulting from the pretreatment of sample cannot filter out the PET glitter. In terrestrial environment, glitter may cause the detrimental effect on soil invertebrate, leading to the survival decrease and reproduction inhibition. Therefore, it is critical to estimate the toxicity of PET glitter as well as biodegradable glitter. In this study, an exposure experiment is conducted to assess the toxicity of microfine PET glitter and two biodegradable glitters on the survival and reproduction of Folsomia candida, which is a collembola species widespread in the world. The results showed that reproduction was inhibited when F. candida expose to microfine PET glitter at the concentration of 1000 mg/kg. In contrast, no significant reproduction inhibition and survival decrease is observed when F. candida expose to two types of biodegradable glitters. Therefore, it implies that biodegradable glitter has lower toxicity than PET glitter, and biodegradable glitter can be an alternative to replace PET glitter. There are two possible mechanisms: Chemical toxicity by glitter additives and alteration of feeding behavior. These assumptions require further investigation, which is pointed out as future direction.
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ItemPer- and Poly-Fluoroalkyl Substances (PFASs) concentration of marine sediments, Port Phillip Bay, Victoria, Australia( 2022)Per and Poly-fluoroalkyl substances (PFASs) have been artificially produced for industrial use due to their stable resistance. However, the extreme stability of this chemical group results them almost impossible to naturally degrade in the environment, especially long-chain PFASs. The bioaccumulation of this contaminant eventually enters animals and humans, increasing the risk of environmental and health problems. Long-chain PFASs, such as PFOS, PFOA and PFHxS, are mainly distributed in the dissolved phases of sediments. The distribution of PFASs is related to the grain size pattern of sediments. Finer sediments with higher soil organic content are likely to increase the sorption ability of PFASs. This research investigates the relationship between PFOS, PFOA and PFHxS concentrations and grain size of core sediments sampled from Port Phillip Bay, Victoria. LCMS/MS utilised to measure the PFASs concentration of the core sediments from Werribee, Sandringham and Central. PFOS, PFOA and PFHxS have been detected from the core sediments and peaked at the sub-surface of the core. For the core sediments, the independent correlations between grain size pattern and PFASs distribution is subtle, therefore, further related research required more experimental samples and parameters like soil organic content to analyse. This study underlines from the concentration distribution of the PFASs of the sample locations, natural controlling factors such as water circulation, water depth of the bay and freshwater input of upper rivers are more directly related compared to the grain size.
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ItemCat Management in Remote Indigenous Communities: Tracking Cats and Owner Perceptions( 2022)Cat management is a complex and controversial topic. In remote Australian Aboriginal communities cats are increasingly becoming a popular and a much-loved companion animal. With limited access to veterinary services, including desexing, cat populations in some remote communities are growing rapidly. This study investigated owner perceptions and relationships with cats, and the movement ecology of cats in two distinct bioregions; the Northern Tanami, and the Tiwi Islands. The study engaged community members through semi-structured interviews, and GPS tracked free-roaming community cats. These cat populations have a close association with humans, increasing the potential transmission of zoonotic diseases. Unmanaged cat populations can have a devastating effect on local biodiversity through predation of native wildlife, and indirectly through disease. However, qualitative enquiry revealed that the human-cat relationship is valued in the remote communities in which research was conducted. To effectively mitigate and prevent adverse outcomes resulting from cat overpopulation, multidisciplinary cat management strategies must be tailored to the needs of the local community, and reflect community traditions, values and ownership practices. Collecting sound information on drivers for cat ownership, local cat numbers and community perspectives is a vital step to inform future cat management in remote Aboriginal communities.
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ItemCurrent state-of-the-art methods, equipment and analyses in soil ecotoxicology( 2022)Soil ecotoxicology study the impact of pollutants on soil ecosystem, which has been developed for more than 50 years. After the first soil ecotoxicology study published in 1960s, the methodology of soil ecotoxicity test was rapidly developed to support the ecological risk assessment. Many standardized ecotoxicity tests were established by international organizations (OECD and ISO) to provide researchers and industries to produce a comparable ecotoxicity data that can improve the understanding of mechanisms of toxicity. However, researchers started to notice the limitations of standardized ecotoxicity test to solve more complicated pollution issues raised in recent years. These issues include the reproducibility and reliability of standard ecotoxicity test, the limited information gained from ecotoxicity test, and the challenge in ecological risk assessment from laboratory experiments to field study. Currently, several novel methodologies, technologies, and analysis in soil ecotoxicology, such as full life cycle ecotoxicity test, continuous monitoring techniques, and eDNA metabarcoding, are proposed as a potential tools used in ecological risk assessment. These novel developments have high potential to deal with the challenges raised in soil ecotoxicology, while no literature review provide a holistic view to summarize them and link with modern pollution issues. Therefore, this article introduce the the historical perspective of soil ecotoxicology, summarize the pollution issues raised in recent years, and point out the state-of-the-art methodology, technology, and analysis in soil ecotoxicology.
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ItemMultiweek-to-seasonal prediction of fire weather in south-eastern Australia( 2021)Weather and climate prediction play a vital role in preparing the public and emergency management authorities for extreme events. In this study, the Australian Bureau of Meteorology’s seasonal forecasting system, ACCESS-S1, is tested on its ability to predict severe fire weather in south-eastern Australia. For the severe event occurring on 07 February 2009 (“Black Saturday”), a hindcast dataset is used to compare model predictions of fire-weather-relevant variables to reanalysis values at lead times of 6, 14, 23, and 69 days. At the longest lead time (69 days), predictions were also compared with those from other years and correlated with the El Niño Southern Oscillation (ENSO) index NINO3.4. At sub-seasonal lead times (6, 14, and 23 days), ACCESS-S1 is found to skilfully predict Tmax values but overpredict rainfall. At the longest lead time (69 days), ACCESS-S1 predicts ordinary counts for hot and dry days during the 2008-2009 summer period, despite this period showing anomalously high counts in the reanalysis. For all hindcast years(1990-2011), model predictions of hot and dry day counts correlate strongly with NINO3.4 values, suggesting an overdependence by the model on the state of ENSO when predicting these variables. Other model biases, such as a warm bias in central Victoria and a wet bias in New South Wales, are suggested to exist due to the routine overprediction of hot day counts (central Victoria) and underprediction of dry day counts (New South Wales) found at these locations. Further investigation is needed to determine the reasons contributing to the model biases identified here and to gain a comprehensive understanding of the model’s abilities.