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The voices we speak and the silences we keep : toward an epistemology of immanence / Margaret Cameron.Cameron, Margaret, 1953-2004. January 1998 (has links)
Bibliography: leaves 243-266. / xi, 266 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Conjunctions between environmental studies and Jungian psychology are explored. Overall provides a critical analysis and deconstruction of western cultural modes which are implicated in contemporary environmental destructions. Simultaneously, alternative ways of being and knowing are constructed, in which hierarchical separations of humans from nature are moved to a respectful relationship. / Thesis (Ph.D.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1998
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Bush fire patchinessHeemstra, Simon Unknown Date (has links)
All bush fires are patchy at some scale and to some degree. In their most obvious form, bush fire patches are unburnt islands of vegetation within a fire boundary. Bush fire patchiness is an important part of the fire regime, because it can affect ecological processes such as local extinction and recolonisation and can contribute to the post-fire resilience of populations of animals that need vegetation cover. During a fire, the survival of plants and animals can often depend on the degree of patchiness. Unburnt patches may therefore affect the post-fire dynamics of plant and animal populations. Continuity of fuel loads is a major contributor to bush fire behaviour including the intensity and rate spread of the fire. Further, the degree of patchiness is one measure of the effectiveness of a hazard-reduction fire in reducing fuel and thus modifying subsequent wildfire behaviour. An understanding of the patchiness of fires is of critical importance for landscape bush fire risk management. Quantifying patchiness is no simple task, partly because of the continuous range of scales at which patchiness occurs and partly because patches cannot always be readily detected by remote sensing techniques, especially in forested systems in which canopy scorch is not closely aligned with burning of the understorey. Moreover, remotely sensed data are expensive at the fine resolution required to detect the small scale patterns that are ecologically relevant (i.e. of the order of metres). In such systems, a method of rapidly assessing patchiness in the field is much needed. The first aim of this study was to develop a field technique for the quantification of patchiness. The second aim was to determine the effectiveness of the technique in estimating overall patchiness in a site, using a simulation model based on a range of known patch sizes and distributions. The third was to use field estimation of patchiness to investigate the environmental parameters that influence the patchiness of fires. A range of methods was assessed and transect sampling the post bush fire landscape using Global Positioning Systems (GPS) to produce a spatial model within a Geographic Information System (GIS) was found to be an accurate and simple method for assessing the patchiness of a fire. This method was time efficient and cost effective. It produced an output that provided a clear description of the overall patchiness of a site as well as the relative distribution of the sizes of the patches. The spatial model can display the distribution of proportion of areas burnt within the landscape. I tested the statistical effectiveness of this transect sampling method using spatial modelling within a GIS. I wrote a program to simulate thousands of transect samples on a range of different spatial arrangements of patches within a landscape. This simulation revealed that the minimum number of transects required to provide an estimate of the actual 'patchiness' is dependent on the type of fire and range between 5 and 10, to obtain 90% accuracy of the estimate of the patchiness. The empirical transect data from each site was used using GIS to develop a spatial model assessing the relative influences of a range of topographic and environmental variables on the patchiness of a fire. The relative influence of these variables was different for each fire. From this analysis, a map was produced from a GIS that described the spatial distribution of patchiness within a given fire. This transect data was graphed to indicate the relative distribution and abundance of unburnt patches. The studies performed indicate these methods have important applications for managing biodiversity and wildfires.
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The voices we speak and the silences we keep : toward an epistemology of immanence / Margaret Cameron.Cameron, Margaret, 1953-2004. January 1998 (has links)
Bibliography: leaves 243-266. / xi, 266 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Conjunctions between environmental studies and Jungian psychology are explored. Overall provides a critical analysis and deconstruction of western cultural modes which are implicated in contemporary environmental destructions. Simultaneously, alternative ways of being and knowing are constructed, in which hierarchical separations of humans from nature are moved to a respectful relationship. / Thesis (Ph.D.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1998
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Reactive in-situ covers for the remediation of mine waste rock using BAUXSOL lime and biosolidsMaddocks, Gregory Arthur Unknown Date (has links)
Failure to design, construct and remediate waste rock and tailings storage facilities at mine sites leads to adverse environmental degradation and unforeseen financial costs. Typical closure options for these facilities include barrier or store and release covers. This thesis investigates the use of reactive in-situ covers as an alternative engineering design approach that involves mixing reagents (e.g. BauxsolTM) with waste rock to neutralise acidity and to immobilise major and minor metals. It was unknown whether this approach could be achieved at a field scale, whether the use of BauxsolTM would achieve its primary objectives, whether there would be adverse effects on the soil chemistry or whether there would be adverse ecotoxicological problems.Four 400 m2 field trials were conducted at a mine site and included a Control; Bauxsol™ (25 kg / m2) plus biosolids (15 kg / m2); Lime (2.5 kg / m2) plus biosolids (15 kg / m2) and a fourth site that was encapsulated with 0.3 m of compacted clay and 0.1 m of topsoil. The results suggest that soil chemistry can be significantly improved by mixing Bauxsol™ with the top 0.5 m of the waste rock profile i.e., creating a reactive in situ cover. This was sufficient to create a root zone up to 1.6 m deep that had pH greater than 5 and lower concentrations of metals measured using a sequential extraction procedure. Treatment of the acid mine waste with Lime did not achieve marked improvement of soil conditions in soil layers below the amended zone. The capping treatment created a topsoil layer with higher pH, but the underlying mine soil remained unimproved. Leachate pH in the Control became increasingly acidic (pH 4.57 to pH 3.95). The addition of Lime and biosolids led to an initial increase in leachate pH, compared to the Control, however this decreased over the duration of the study (pH 5.37 to pH 4.89). In the Bauxsol™ and biosolids treatment leachate pH increased to 6.92 after the first rainfall event and continued to increase over the duration of the study to pH 7.4. After 24 months metal leachate concentrations (mg / L) in the lysimeters for Al, Cd, Cu, Mn and Zn were (Control: 32.6, 5.7, 12.7, 39.3, 121.8), (Bauxsol™: 0.07, 0.02, 0.07, 0.57, 0.23) and (Lime: 2.19, 1.19, 2.33, 3.6, 28.4). No leachate was available for collection from the Clay treatment indicating that this technique was functioning in terms of minimising the infiltration of water into the mine soil.Ecotoxicological studies of major and minor metals in eucalypt leaves from the field trials and earthworm bioaccumulation studies were undertaken. The Bauxsol™, Ca(OH)2 and Clay treatments in the field trials allowed good tree growth of four eucalypt species, compared to the Control. There was no statistical difference in tree growth between the Bauxsol™, Lime or Clay treatments over the two years of monitoring. However the growth of one tree species was poor in the Bauxsol™ treatment.Laboratory bioaccumulation assessments found that there was good motility and no mortality of the earthworm species E. fetida after 28 days exposure to metal loaded BauxsolTM. The bioaccumulation of metals in E. fetida and bioaccumulation factors were below reported toxicity thresholds to cause mortality and below reported bioaccumulation factors for moderately contaminated soils, indicating that the metals bound to the Bauxsol™ reagents are mostly non-bioavailable E. fetida. Analyses of the 20 % treatment at 28 days using a sequential extraction procedure showed that > 95 % of the metals are bound within the Fe / Mn oxide fractions. However, changes occurred in metal fractionation after exposure to E. fetida for Cd, Cr and Fe, Mn. The data also showed that the exchangeable (1M MgCl2) and the Toxicity Characteristic Leaching Procedure extractant are useful as indicators of metal bioavailability to E. fetida.
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Bush fire patchinessHeemstra, Simon Unknown Date (has links)
All bush fires are patchy at some scale and to some degree. In their most obvious form, bush fire patches are unburnt islands of vegetation within a fire boundary. Bush fire patchiness is an important part of the fire regime, because it can affect ecological processes such as local extinction and recolonisation and can contribute to the post-fire resilience of populations of animals that need vegetation cover. During a fire, the survival of plants and animals can often depend on the degree of patchiness. Unburnt patches may therefore affect the post-fire dynamics of plant and animal populations. Continuity of fuel loads is a major contributor to bush fire behaviour including the intensity and rate spread of the fire. Further, the degree of patchiness is one measure of the effectiveness of a hazard-reduction fire in reducing fuel and thus modifying subsequent wildfire behaviour. An understanding of the patchiness of fires is of critical importance for landscape bush fire risk management. Quantifying patchiness is no simple task, partly because of the continuous range of scales at which patchiness occurs and partly because patches cannot always be readily detected by remote sensing techniques, especially in forested systems in which canopy scorch is not closely aligned with burning of the understorey. Moreover, remotely sensed data are expensive at the fine resolution required to detect the small scale patterns that are ecologically relevant (i.e. of the order of metres). In such systems, a method of rapidly assessing patchiness in the field is much needed. The first aim of this study was to develop a field technique for the quantification of patchiness. The second aim was to determine the effectiveness of the technique in estimating overall patchiness in a site, using a simulation model based on a range of known patch sizes and distributions. The third was to use field estimation of patchiness to investigate the environmental parameters that influence the patchiness of fires. A range of methods was assessed and transect sampling the post bush fire landscape using Global Positioning Systems (GPS) to produce a spatial model within a Geographic Information System (GIS) was found to be an accurate and simple method for assessing the patchiness of a fire. This method was time efficient and cost effective. It produced an output that provided a clear description of the overall patchiness of a site as well as the relative distribution of the sizes of the patches. The spatial model can display the distribution of proportion of areas burnt within the landscape. I tested the statistical effectiveness of this transect sampling method using spatial modelling within a GIS. I wrote a program to simulate thousands of transect samples on a range of different spatial arrangements of patches within a landscape. This simulation revealed that the minimum number of transects required to provide an estimate of the actual 'patchiness' is dependent on the type of fire and range between 5 and 10, to obtain 90% accuracy of the estimate of the patchiness. The empirical transect data from each site was used using GIS to develop a spatial model assessing the relative influences of a range of topographic and environmental variables on the patchiness of a fire. The relative influence of these variables was different for each fire. From this analysis, a map was produced from a GIS that described the spatial distribution of patchiness within a given fire. This transect data was graphed to indicate the relative distribution and abundance of unburnt patches. The studies performed indicate these methods have important applications for managing biodiversity and wildfires.
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An approach to dynamic environmental life-cycle assessment by evaluating structural economic sequences /Gloria, Thomas P. January 1900 (has links)
Thesis (Ph.D.)--Tufts University, 2000. / Adviser: Stephen H. Levine. Submitted to the Dept. of Civil Engineering. Includes bibliographical references (leaves 259-277). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
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Environmental valuation and policy : applications in the management of endangered species, recreation, and tourism /Fredman, Peter, January 1900 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
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Studies on organochlorine environmental contaminants with emphasis on analytical methods and occurrence in humans /Weistrand, Cecilia, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 7 uppsatser.
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Health effects of environmental lead exposure in children /Osman, Katarina, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.
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Studies on the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on vitamin A homeostasis /Nilsson, Charlotte, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.
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