Launceston, a city with a population of approximately 80,000 located in the north of Tasmania, Australia, regularly experiences high levels of air pollution during winter. Ambient PM10 (particulate matter with an aerodynamic diameter smaller than 10 micrometres) levels exceed the Australian 24-hour guideline of 50 micrograms/m3 around 20-40 times during the May to September period each year. This is generally attributed to residential woodburning, with approximately one third of households using woodheaters or open fireplaces. This thesis reports on investigations into characterising and quantifying the contribution of woodsmoke to wintertime air pollution in Launceston. An historical record of air quality in Launceston was reconstructed using polycyclicaromatic hydrocarbons (PAHs) as surrogates for air pollution in a dated sediment core taken from the upper Tamar Estuary. The overall depth profile showed that levels of PAHs began increasing at the end of the 19th century and have been relatively steady since the 1930s. Pyrogenic source ratios similar to woodburning were found in both atmospheric and sedimentary samples, although quantification of the woodburning contribution was not possible using PAHs alone. Factors affecting atmospheric sampling of PAHs were investigated, including the impact of sampling rate, the vapour-particle phase distribution on various components of the sampling system and degradation caused by different filter media. Because of the inability of PAHs to differentiate between fossil fuel and wood combustion there was a need to identify alternative tracers for wood combustion. A dilution tunnel was used to collect emissions from woodheaters operated with different airflow settings, and around 100 organic compounds were quantified. Although the majority of compounds were not detected in ambient air samples, levoglucosan was found to be not degraded in the atmospheric samples and was identified as a consistent tracer for woodsmoke. Levoglucosan concentrations in ambient PM10 indicated that woodheaters contributed about 80% of wintertime air pollution in Launceston. To validate the use of levoglucosan as a tracer for woodsmoke, the contribution of biomass and fossil fuel sources of carbon to Launceston ambient aerosols was determined by measuring the carbon-14 content using accelerator mass spectrometry. Fossil sources had a relatively low and constant input irrespective of the particulate loading, consistent with transport-related emissions. Conversely, the biomass input, most likely from woodsmoke, was found to increase linearly with particulate loading, and contributed around 97-99% of the total organic carbon fraction of Launceston wintertime PM10. A modified combustion method was developed for samples collected on borosilicate filter media.

The central focus of this thesis is the role of narratives in the construction, mobilisation and validation of scientific knowledge claims. With an epistemological commitment to constructivism, which conceptualises scientific knowledge as the product of a process (and not something revealed), the regulatory domain of impact assessment in respect of Basslink, a 350 kilometre power cable that will link Tasmania to the Australian mainland across Bass Strait, has been used as a case study to undertake the task of tracing the translations that intervened between assessment process inputs and outputs - contributions deemed 'scientific' and 'independent' by the project's proponents and supporters. Specifically, the knowledge claims tendered by Hydro Tasmania, Tasmania's hydro-electricity generator, in respect of predicted environmental impacts on the Gordon River arising from changes to river flows required to generate and export hydro-electricity across Basslink, have been examined. The central epistemological question has been how, given the extent of the contingencies and indeterminacies in predictive economic and environmental modelling inputs and outputs used to substantiate the impacts and benefits of Basslink (which have been detailed in the thesis), was Hydro Tasmania's case in support of the development made durable and, thereby, legitimated by the decision-making body charged with the task of assessing the project. This study follows Hydro Tasmania's knowledge claims in respect of the Gordon River impacts through the process and demonstrates the pivotal role of narratives and the extent to which they can bridge empirical gaps, explain and obscure inconsistencies, erase unexpected model outputs, contextualise findings and mobilise ontological claims. The tension between the fulfilment of disclosure requirements upon proponents by means of 'scientific facts'and the extent to which issues such as trust, accountability and past track record, bear upon people's uptake of these 'facts' is also examined in this work.

China is now the world's largest food producer for many food categories, and has recently embarked on a major conversion to organic agriculture. Australian farmers have described their industry as in crisis due to increasing competition from imports; they have called for strengthening of country of origin labelling on food. Priestley (2005) noted the absence of data on the premium Australian consumers will pay, if any, for Australian food produce. Halpin (2004) has reported that the current premiums on organic food are well beyond what Australian consumers are likely to be willing to pay, and that this will probably inhibit the growth of the industry in Australia. Vogl, Kilcher & Schmidt (2005) declare that consumers expect organic produce to be labelled with a regional identity. The present study set out to establish the values consumers place on organic, on provenance, and on faux-organic claims (Type II eco-labels), and to determine the interactions between these factors. Australian consumers (N=221) were surveyed online. Organic was valued at an 8.12% premium, and Certified Organic was valued at a 15.63% premium. The provenance Australia was valued at a 25.98% premium over China, and Tasmania was valued at a 31.59% premium over China. Both Natural and Eco added value, 2.48% and 2.84% respectively. Certified Organic attracted a lower premium when coupled with China (11.62%). This Organic x Provenance interaction was consistent with respondents declaring they lacked trust in Chinese labelling. Interaction effects for eight demographic variables, including age, education, and place of residence, are reported. Gender and income do not have a significant influence on consumer values. This study found that adjunctive labelling offers both Australian and Chinese producers the opportunity to add value to their produce. It found that Australian producers would be beneficiaries from implementation of the Fair Dinkum Food Campaign's call for Country of Origin Labelling (CoOL), which is currently lacking on processed food. It establishes that organic is a path for both Australian and Chinese producers to add value. It suggests that China's push into organic production has the potential to lead the world to an organic future, and continuing on this path may give China the opportunity to redefine the standard for internationally traded food as Certified Organic.

The crown structure and canopy arthropods of Eucalyptus obliqua were studied at the Warra Long Term Ecological Research Site in the wet sclerophyll forests of Southern Tasmania. Eight 100 year old and eight old-growth (between 300-500 years old) trees were studied in pairs. Despite their critical role in the economy and ecology of Tasmania, few studies have addressed the canopy arthropod biodiversity of these trees. The crown structure was mapped by recording a vector in spherical space for every branch. 3- dimensional computer models were generated to aid in illustrating the tree maps. Sticky traps, flight intercept traps, and funnel crawl traps were placed in the crown to sample mobile arthropods. The age classes were quantifiably different in crown structure. 100 year old trees had young mature crowns of original branches. Old trees had either senescent original crowns or resprouted epicormic secondary crowns. Old trees expressed a greater variability in crown structure, and were more complex as measured by the amount of information required to display the computer image. Structural attributes such as hollows, dead tops, dead flanks, trunk fissures, burls, vascular epiphytes, snapped trunks, and litter collections were all present more often in the old trees than the 100 year old trees.

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Environmental management in modern industry entails much more than simply measuring the level of contaminants at the discharge point of a chimney stack or pipeline and operating within defined licence limits. It involves: 1) Understanding the environmental risks associated with the industrial operation; 2) Quantifying the environmental assets at risk; 3) Evaluating the environmental challenge from the industry (determining the likely effect of particular emission levels on different environments); 4) Monitoring the condition of environmental assets in response to this challenge; 5) Devising appropriate remedial action where necessary. This study aimed to provide a rigorous and effective framework for decision making concerning vegetated landscapes surrounding industrial premises, particularly those associated with emissions of pollutants to air. Three Alcoa of Australia managed facilities in Victoria were used to develop and test the procedures, namely a coastal site at Point Henry, Geelong, a hinterland forest and heath site at Anglesea and a coastal heath site at Portland. The three facilities were involved in the aluminium smelting industry and the major atmospheric emissions were gaseous and particulate fluorides and sulfur dioxide. Analyses of vegetation distribution and condition were undertaken in order to establish whether the industrial activities at the three sites could be identified as the causes of changes in vegetation. A geographic information system (GIS) was implemented at each facility, to contain cadastral information as well as records of the physical environment and plant and animal species occurrences and condition, where appropriate. The GIS was used to create a surface of vegetation condition over the area of interest at the time of assessment and then over time to evaluate vegetation change and relationship to meteorological and production data. Baseline vegetation condition was established for each facility using large-scale high quality aerial photography and multi-spectral imagery. The photography for each site contained large amounts of latent information on vegetation distribution and condition. When properly rectified and geo-referenced, the images became accessible and open to manipulation within the GIS. At each of the three sites investigated, image classes were selected that provided appropriate detail for the vegetation type. In effect the image became a surrogate of the vegetation frozen in time and space. The ability to extract information on past vegetation condition was shown to be a very valuable asset providing the opportunity to generate new contemporaneous data to augment poor or lost historical data. The process was illustrated by developing vegetation change maps and trend information using past and current photography and limited historical field data. A verified emission model was applied to two of the facilities (Anglesea and Portland) to predict emission effects over the vegetated areas. These were used to evaluate current vegetation condition and change in terms of industrial challenge and other change agencies known or suspected. In each case, further developments of the model were required in order to achieve acceptable predictions of known atmospheric and air pollutant conditions. The investigations at Anglesea demonstrated the importance of fine-scale topographic description and meteorological modelling in order to reconcile modelled and observed environmental conditions in hilly coastal terrain. At Portland, the study revealed the importance of marine aerosols in the distribution and deposition of fluoride in the vicinity of the source. Within the broad framework of vegetation type and general condition at Anglesea and Portland, differences at the micro-scale of individual plants and clumps of plants were examined using multi-spectral imagery. Here differences in image characteristics that related to increased pigmentation and loss of chlorophyll in leaves and increased amounts of dead tissue on plants were evaluated. The change agents for the detected differences within sets and between sets of imagery were analysed and again shown to be mainly non-industrial. Only at Portland did atmospheric emissions from the aluminium smelter play a role at some locations, and then only because the effect was being reinforced by other factors (lack of burning and drought). At Portland, population data for associated fauna and an orchid were examined in relation to the baseline vegetation condition, vegetation change and industrial impact. The distribution and welfare of these species were shown to be generally dependent on vegetation condition and other non-industrial factors. If the vegetation overall was maintained in a condition of vigorous growth and structural diversity, it could be expected that specific dependant flora and fauna would thrive within it. The exception was the orchid, which was shown to be sensitive to emissions and could only thrive in its natural habitat in the vicinity of the smelter if protected by screening vegetation or nurtured by an intensive set of cultural practices that were developed as a result of this study.

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