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.
| Identifer | oai:union.ndltd.org:ADTP/290637 |
| Creators | Hill, Richard J. |
| Source Sets | Australiasian Digital Theses Program |
| Detected Language | English |
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