Dissertations / Theses on the topic 'Mt Lofty Ranges'

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1

Akter, Shirin. "Regional flood estimation method for the Mt. Lofty Ranges /." Title page, abstract and contents only, 1992. http://web4.library.adelaide.edu.au/theses/09ENS/09ensa315.pdf.

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2

Chalklen, Andrew John. "Outdoor recreation potential of forested land in the Mt. Lofty Ranges /." Title page, contents and abstract only, 1985. http://web4.library.adelaide.edu.au/theses/09AR/09arc436.pdf.

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3

Dalby, Paul Reginald. "Competition between earthworms in high rainfall pastures in the Mt. Lofty Ranges, South Australia." Title page, contents and summary only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phd137.pdf.

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Copy of author's previously published work inserted. Bibliography: leaves 261-306. The objectives of the project were: i. to determine whether there are competitive interactions between Aporrectodea trapezoides and A. caliginosa and A. rosea.--ii. to investigate compeditive interactions between A. calignosa, Microscolex dubius and A. trapezoides.--iii . to determine the likely impact of A. longa on soil fauna, especially the native earthworm, Gemascolex lateralis, in native ecosystems.
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4

Rogers, Beatrice R. "The habitat requirements of Brown treecreepers, Climacteris picumnus, in the Mt. Lofty Ranges /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09SB/09sbr7244.pdf.

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Thesis (B. Sc.)--University of Adelaide, Department of Zoology.
Cover title. "Submitted in partial fulfillment of the requirements for the degree of Bachelor of science with Honors, Department of Zoology, University of Adelaide, May 1998" -- Cover. Bibliography: p. 46-53.
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5

Marchesan, Doreen. "Presence, breeding activity and movement of the yellow-footed antechinus (Antechinus flavipes), in a fragmented landscape of the southern Mt Lofty Ranges." Title page, contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09AS/09asm316.pdf.

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"September 2002" Bibliography: leaves 77-85. Examines the persistence of the yellow-footed antechinus using live trapping in small, remnant patches and strips of forest, to document autecological sata and the investgate occurrence, breeding activity and inter-patch movements. Radio-tracking was conducted to compare home range properties of lactating females in restricted and unrestricted habitat.
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6

Bryan, Brett. "The ecological, psychological and political issues surrounding the management of koalas in southern Mt Lofty Ranges /." Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09ENV/09envb915.pdf.

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Thesis (M. Env. Sc.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1996.
Two col. maps in pocket on back end-paper. Includes bibliographical references (leaves 118-135).
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7

Yassaghi, Ali. "Geometry, kinematics, microstructure, strain analysis, and P-T conditions of the shear zones and associated ductile thrusts in the southern Mt. Lofty Ranges/Adelaide Hills area, South Australia /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phy29.pdf.

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8

Bastian, Richard George. "Three-dimensional modelling, simulation and visualisation of minor structures in shear zones, using samples collected from the Northern Mt. Lofty Ranges of the Southern Adelaide Fold-thrust belt /." Title page, abstract and table of contents only, 1998. http://web4.library.adelaide.edu.au/theses/09SB/09sbb326.pdf.

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9

Dare, David L. "The anatomy of a fold and thrust terrane in the northern Mt. Lofty Ranges, South Australia : an appraisal of the structural evolution and the implications for gold and base metal mineralization in the region of the Ulooloo Gold Reserve /." Title page, contents and introduction only, 1995. http://web4.library.adelaide.edu.au/theses/09S.B/09s.bd217.pdf.

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Thesis (B. Sc.(Hons.))--University of Adelaide, Dept. of Geology and Geophysics, 1996.
Australian National Grid reference Hallett 6631-11 1:50 000 sheet Caroona 6731-111 1:50 000 sheet. Includes bibliographical references.
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10

Deegan, Brian Martin. "Ecological benefits of 'environmental flows' in the Eastern Mt. Lofty Ranges." 2007. http://hdl.handle.net/2440/41432.

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This thesis examined the impact of anthropogenic alterations in four riverine catchments of the Eastern Mt. Lofty Ranges, South Australia, to identify if creek restoration via environmental flows is a viable management option and if so, to determine; 1) Whether an aquatic/riparian viable seed bank was present and if so what was its composition 2) The ecological condition of selected riverine reaches. This in combination with the seed bank study would identify those creeks that would most benefit from the imposition of environmental flows 3) The response of key species to the water regimes likely to result from the imposition of environmental flows 4) The influence of nutrient enrichment under a fluctuating water level and to use this information to formulate best practice policy for environmental flows 5) Whether aquatic plants promoted by environmental flows were a significant fraction of the diet for higher trophic levels represented by Trichopterans and Amphipods. The seed banks were of comparable density (ranging from 4,000 to 110,000 seeds m-2) and species richness (ranging from 13 to 20 aquatic / riparian species) to the seed banks of other Australian rivers and wetlands, but this varied significantly among riverine sections and across catchments. Out of a total of 81 species recorded, 51 were classified as terrestrial (63% of all species recorded). What is of greater concern was the number of exotic (both aquatic and terrestrial) species recorded: 43% of the species recorded in the Angas, 47% of the species in the Finniss, 39% of the species in Tookayerta creek and 43% of the species recorded in Currency creek were exotic, which are significantly higher in comparison to other Australian studies. There were 24 to 28 aquatic/riparian species recorded in the extant vegetation of each catchment that were not recorded in their seed banks. Likewise, a number of species (3 to 7) were recorded in each catchments seed bank that were not recorded in the extant vegetation of those catchments. A species of particular interest is Crassula sieberana, which is on the State endangered plant species list. Indices for assessing the ecological condition, health or integrity of a river or riparian habitat were employed to investigate the relationship between the river/riparian habitat and the land and water management practices associated with those habitats. Of the four catchments surveyed, each catchment identified a unique set of site parameters (subindex indicators) that were strongly correlated with its ecological condition. Indicator species analyses revealed pasture grasses to be a significant indicator of reaches in very poor condition (p = 0.0010) along the Finniss and Baumea juncea of those reaches in good condition (p = 0.0230). Along the Angas, Cotula coronopifolia was an indicator of those reaches in average condition (p = 0.0240) and along Currency creek, Cladium procerum was an indicator of those reaches in good condition (p = 0.0190). However, when all 115 surveyed reaches were analysed together, those reaches of average to excellent ecological condition were all strongly correlated (R2 = 0.50) with the subindex indicators: bank stability, % riparian cover, grazing, fenced, aquatic wood, and width of the riparian vegetation. This would indicate that these subindex indicators are the main site parameters determining the ecological condition of a riverine reach and hence its restoration potential. Those catchments or sub-catchments containing a high proportion of reaches classified to be in poor to very poor condition had significantly reduced seed banks. The influence of water level fluctuations (±15 cm, ±30 cm and ±45 cm) on the growth of four species of emergent macrophytes (Cyperus vaginatus, Phragmites australis, Typha domingensis and Triglochin procerum) were species dependent. These species naturally inhabits different zones across the elevation gradient. C. vaginatus, which has a high elevation preference, was strongly inhibited by increasing water depth and fluctuations in water levels. In contrast, species with an intermediate elevation preference, such as Phragmites australis and Typha domingensis, were more tolerant to both depth and water level fluctuations. However, the biomass and relative growth rate (RGR) of T. domingensis and P. australis were depressed when grown under the combination of deep elevation and a highly fluctuating water level (±45 cm). Between the static and ±45 cm amplitude treatments, growth of T. domingensis was inhibited by 52%. The growth of P. australis appeared to be enhanced by fluctuating water levels and only showed a severe drop-off in growth in the deep elevation, ±45 cm amplitude treatment. In C. vaginatus the RGR was dependent of the average emergent surface area (and the implied rate of carbon acquisition)(p<0.0001; r2=0.7196; F=87.276; n=36; RGR (mg g-1 day-1) = -5.096 + 4.313 × ln (Average emergent surface area (cm2)), but this was not the case in P. australis and T. domingensis (p>0.05) even when the photosynthetic canopy was partially inundated by rising water levels. Yet these two species demonstrated different growth rates when grown under different water regime amplitudes and at different elevations. Growth of T. procerum did not respond to either amplitude or elevation, but its RGR remained negative. This suggests that another factor(s) was limiting the growth of P. australis, T. domingensis and possibly T. procerum, a factor that varies with water level. Cyperus gymnocaulos had significantly increased plant performance (p <.0001) with increased nutrient loading rates but this effect was significantly reduced under a fluctuating water regime (p =0.0007). Remarkably, under a fluctuating regime, P. australis had a significant reduction in performance with increased nutrient loading rates (p =0.0013), whereas T. domingensis performance was significantly limited (p =0.034) even with increased nutrient loading rates. T. procerum too had increased plant performance with increased nutrient loading rates but this effect was reduced under a fluctuating regime. The morphological response by T. procerum demonstrates that it is mainly limited by the nutrient loading rates and not the water regime. However, it was significantly limited/reduced by its increased turnover rates caused by a stochastic fluctuating water regime. Illustrating that in fact the effects of nutrient enrichment on T. procerum were independent of water regime but bearing in mind that water regime is the primary factor determining the productivity of this species. For those species with higher elevation preferences, e.g. C. gymnocaulos, or low elevation preference, e.g. T. procerum, the effects of nutrient loading are independent of water regime, whereas those species with an intermediate elevation preference, e.g. P. australis and T. domingensis the effects of nutrient loading are largely dependent on the water regime. Amphipoda and Trichoptera selectively fed on succulent semi-emergent macrophytes across sites of average to excellent ecological condition (31-64% to 65-97% of diet), depending on availability. These semi-emergent macrophytes contained the lowest C:N ratio (≈10:1), closest to that of their consumers (≈5:1) and therefore the highest nutritional content. In degraded riverine reaches, there were limited food resources available, hence course particulate organic matter (CPOM) formed the main dietary components of Amphipoda (20-53% of diet) even though it had the highest C:N ratio (≈40:1). At site VP. 1, filamentous algae was the main dietary component of Trichoptera (48-64% of diet) due to its availability and its low C:N ratio (≈14:1) in comparison to the other primary sources available. The imbalanced consumer-resource nutrient ratios in these degraded riverine reaches are likely to impose constraints on the growth and reproduction of their aquatic shredder communities with probable knock-on effects at higher trophic levels. The installation of environmental flows to restore and promote aquatic/riparian plant communities, which in turn would benefit higher trophic organisms, is a viable and realistic management option along selected reaches. Those selected reaches contain a significant aquatic/riparian seed bank and with sufficient physical habitat remaining to promote their germination and establishment. However, the imposition of environmental flows as a control measure to prevent the colonisation and dominance of particular species (T. domingensis and P. australis) was deemed to be redundant as a management technique given the limited water resources available.
Thesis (Ph.D.) -- School of Earth and Environmental Sciences, 2007
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11

Deegan, Brian Martin. "Ecological benefits of 'environmental flows' in the Eastern Mt. Lofty Ranges." Thesis, 2007. http://hdl.handle.net/2440/41432.

Full text
Abstract:
This thesis examined the impact of anthropogenic alterations in four riverine catchments of the Eastern Mt. Lofty Ranges, South Australia, to identify if creek restoration via environmental flows is a viable management option and if so, to determine; 1) Whether an aquatic/riparian viable seed bank was present and if so what was its composition 2) The ecological condition of selected riverine reaches. This in combination with the seed bank study would identify those creeks that would most benefit from the imposition of environmental flows 3) The response of key species to the water regimes likely to result from the imposition of environmental flows 4) The influence of nutrient enrichment under a fluctuating water level and to use this information to formulate best practice policy for environmental flows 5) Whether aquatic plants promoted by environmental flows were a significant fraction of the diet for higher trophic levels represented by Trichopterans and Amphipods. The seed banks were of comparable density (ranging from 4,000 to 110,000 seeds m-2) and species richness (ranging from 13 to 20 aquatic / riparian species) to the seed banks of other Australian rivers and wetlands, but this varied significantly among riverine sections and across catchments. Out of a total of 81 species recorded, 51 were classified as terrestrial (63% of all species recorded). What is of greater concern was the number of exotic (both aquatic and terrestrial) species recorded: 43% of the species recorded in the Angas, 47% of the species in the Finniss, 39% of the species in Tookayerta creek and 43% of the species recorded in Currency creek were exotic, which are significantly higher in comparison to other Australian studies. There were 24 to 28 aquatic/riparian species recorded in the extant vegetation of each catchment that were not recorded in their seed banks. Likewise, a number of species (3 to 7) were recorded in each catchments seed bank that were not recorded in the extant vegetation of those catchments. A species of particular interest is Crassula sieberana, which is on the State endangered plant species list. Indices for assessing the ecological condition, health or integrity of a river or riparian habitat were employed to investigate the relationship between the river/riparian habitat and the land and water management practices associated with those habitats. Of the four catchments surveyed, each catchment identified a unique set of site parameters (subindex indicators) that were strongly correlated with its ecological condition. Indicator species analyses revealed pasture grasses to be a significant indicator of reaches in very poor condition (p = 0.0010) along the Finniss and Baumea juncea of those reaches in good condition (p = 0.0230). Along the Angas, Cotula coronopifolia was an indicator of those reaches in average condition (p = 0.0240) and along Currency creek, Cladium procerum was an indicator of those reaches in good condition (p = 0.0190). However, when all 115 surveyed reaches were analysed together, those reaches of average to excellent ecological condition were all strongly correlated (R2 = 0.50) with the subindex indicators: bank stability, % riparian cover, grazing, fenced, aquatic wood, and width of the riparian vegetation. This would indicate that these subindex indicators are the main site parameters determining the ecological condition of a riverine reach and hence its restoration potential. Those catchments or sub-catchments containing a high proportion of reaches classified to be in poor to very poor condition had significantly reduced seed banks. The influence of water level fluctuations (±15 cm, ±30 cm and ±45 cm) on the growth of four species of emergent macrophytes (Cyperus vaginatus, Phragmites australis, Typha domingensis and Triglochin procerum) were species dependent. These species naturally inhabits different zones across the elevation gradient. C. vaginatus, which has a high elevation preference, was strongly inhibited by increasing water depth and fluctuations in water levels. In contrast, species with an intermediate elevation preference, such as Phragmites australis and Typha domingensis, were more tolerant to both depth and water level fluctuations. However, the biomass and relative growth rate (RGR) of T. domingensis and P. australis were depressed when grown under the combination of deep elevation and a highly fluctuating water level (±45 cm). Between the static and ±45 cm amplitude treatments, growth of T. domingensis was inhibited by 52%. The growth of P. australis appeared to be enhanced by fluctuating water levels and only showed a severe drop-off in growth in the deep elevation, ±45 cm amplitude treatment. In C. vaginatus the RGR was dependent of the average emergent surface area (and the implied rate of carbon acquisition)(p<0.0001; r2=0.7196; F=87.276; n=36; RGR (mg g-1 day-1) = -5.096 + 4.313 × ln (Average emergent surface area (cm2)), but this was not the case in P. australis and T. domingensis (p>0.05) even when the photosynthetic canopy was partially inundated by rising water levels. Yet these two species demonstrated different growth rates when grown under different water regime amplitudes and at different elevations. Growth of T. procerum did not respond to either amplitude or elevation, but its RGR remained negative. This suggests that another factor(s) was limiting the growth of P. australis, T. domingensis and possibly T. procerum, a factor that varies with water level. Cyperus gymnocaulos had significantly increased plant performance (p <.0001) with increased nutrient loading rates but this effect was significantly reduced under a fluctuating water regime (p =0.0007). Remarkably, under a fluctuating regime, P. australis had a significant reduction in performance with increased nutrient loading rates (p =0.0013), whereas T. domingensis performance was significantly limited (p =0.034) even with increased nutrient loading rates. T. procerum too had increased plant performance with increased nutrient loading rates but this effect was reduced under a fluctuating regime. The morphological response by T. procerum demonstrates that it is mainly limited by the nutrient loading rates and not the water regime. However, it was significantly limited/reduced by its increased turnover rates caused by a stochastic fluctuating water regime. Illustrating that in fact the effects of nutrient enrichment on T. procerum were independent of water regime but bearing in mind that water regime is the primary factor determining the productivity of this species. For those species with higher elevation preferences, e.g. C. gymnocaulos, or low elevation preference, e.g. T. procerum, the effects of nutrient loading are independent of water regime, whereas those species with an intermediate elevation preference, e.g. P. australis and T. domingensis the effects of nutrient loading are largely dependent on the water regime. Amphipoda and Trichoptera selectively fed on succulent semi-emergent macrophytes across sites of average to excellent ecological condition (31-64% to 65-97% of diet), depending on availability. These semi-emergent macrophytes contained the lowest C:N ratio (≈10:1), closest to that of their consumers (≈5:1) and therefore the highest nutritional content. In degraded riverine reaches, there were limited food resources available, hence course particulate organic matter (CPOM) formed the main dietary components of Amphipoda (20-53% of diet) even though it had the highest C:N ratio (≈40:1). At site VP. 1, filamentous algae was the main dietary component of Trichoptera (48-64% of diet) due to its availability and its low C:N ratio (≈14:1) in comparison to the other primary sources available. The imbalanced consumer-resource nutrient ratios in these degraded riverine reaches are likely to impose constraints on the growth and reproduction of their aquatic shredder communities with probable knock-on effects at higher trophic levels. The installation of environmental flows to restore and promote aquatic/riparian plant communities, which in turn would benefit higher trophic organisms, is a viable and realistic management option along selected reaches. Those selected reaches contain a significant aquatic/riparian seed bank and with sufficient physical habitat remaining to promote their germination and establishment. However, the imposition of environmental flows as a control measure to prevent the colonisation and dominance of particular species (T. domingensis and P. australis) was deemed to be redundant as a management technique given the limited water resources available.
Thesis (Ph.D.) -- School of Earth and Environmental Sciences, 2007
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12

Dalby, Paul Reginald. "Competition between earthworms in high rainfall pastures in the Mt. Lofty Ranges, South Australia / Paul Reginald Dalby." Thesis, 1996. http://hdl.handle.net/2440/18758.

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Copy of author's previously published work inserted.
Bibliography: leaves 261-306.
xxix, 308 leaves : ill. (some col.), maps ; 30 cm.
The objectives of the project were: i. to determine whether there are competitive interactions between Aporrectodea trapezoides and A. caliginosa and A. rosea.--ii. to investigate compeditive interactions between A. calignosa, Microscolex dubius and A. trapezoides.--iii . to determine the likely impact of A. longa on soil fauna, especially the native earthworm, Gemascolex lateralis, in native ecosystems.
Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, 1996
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13

Marchesan, Doreen. "Presence, breeding activity and movement of the yellow-footed antechinus (Antechinus flavipes), in a fragmented landscape of the southern Mt Lofty Ranges." Thesis, 2002. http://hdl.handle.net/2440/109645.

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Examines the persistence of the yellow-footed antechinus using live trapping in small, remnant patches and strips of forest, to document autecological sata and the investgate occurrence, breeding activity and inter-patch movements. Radio-tracking was conducted to compare home range properties of lactating females in restricted and unrestricted habitat.
Thesis (M.App.Sc.) -- University of Adelaide, Dept. of Animal Science, 2002
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14

Ottewell, Kym M. "A survey of the reproductive ecology and patterns of pollen-mediated gene flow in Eucalyptus camaldulensis and E.leucoxylon paddock trees." 2007. http://hdl.handle.net/2440/57106.

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Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library.
In many areas of south-eastern Australia, the clearance of temperate eucalypt woodlands for agriculture has been so extensive that only scattered remnant trees remain. The loss of habitat and increased spatial isolation of trees in paddocks is predicted to lead to a decline in plant fecundity because of disruptions to plant-pollinator interactions, which has important implications for the long-term persistence and maintenance of these populations. In order to assess the ability of paddock trees to contribute to population regeneration, this study assessed the reproductive viability and patterns of mating of paddock trees of two woodland species, Eucalyptus camaldulensis and E.leucoxylon in the Mt. Lofty Ranges, South Australia. This study revealed that paddock tree populations of E. camaldulensis and E.leucoxylon were reproductively viable and received sufficient visits by pollinators that resulted in high outcrossing rates. The results suggest that seed collected from these paddock trees are both genetically diverse and representative of adult populations. Therefore, such trees could contribute successfully to conservation strategies that sought to regenerate cleared paddocks.
http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1292793
Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007
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15

Ottewell, Kym Marie. "A survey of the reproductive ecology and patterns of pollen-mediated gene flow in Eucalyptus camaldulensis and E.leucoxylon paddock trees." Thesis, 2007. http://hdl.handle.net/2440/57106.

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Abstract:
Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library.
In many areas of south-eastern Australia, the clearance of temperate eucalypt woodlands for agriculture has been so extensive that only scattered remnant trees remain. The loss of habitat and increased spatial isolation of trees in paddocks is predicted to lead to a decline in plant fecundity because of disruptions to plant-pollinator interactions, which has important implications for the long-term persistence and maintenance of these populations. In order to assess the ability of paddock trees to contribute to population regeneration, this study assessed the reproductive viability and patterns of mating of paddock trees of two woodland species, Eucalyptus camaldulensis and E.leucoxylon in the Mt. Lofty Ranges, South Australia. This study revealed that paddock tree populations of E. camaldulensis and E.leucoxylon were reproductively viable and received sufficient visits by pollinators that resulted in high outcrossing rates. The results suggest that seed collected from these paddock trees are both genetically diverse and representative of adult populations. Therefore, such trees could contribute successfully to conservation strategies that sought to regenerate cleared paddocks.
Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007
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16

Croft, Sonia Julie. "Canopy dieback and decline in pink gums, Eucalyptus fasciculosa, F.Muell in the Mt Lofty Ranges and adjoining plains." Thesis, 2017. http://hdl.handle.net/2440/111991.

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In Australia, widespread decline of Eucalyptus species has been occurring largely since the 1970s. In southern Australia, pink gums (Eucalyptus fasciculosa F. Muell) occur within a restricted area, and have been assigned a conservation rating due to perceived canopy decline. This study aimed to describe the population structure and canopy condition of pink gums in the Mt Lofty Ranges and surrounding plains, and to distinguish between causes of short-term dieback and long-term decline. I hypothesised that decline in pink gum woodlands was most likely to be because of one or more of the following: (1) long-term and continuous mistletoe infection; (2) declining annual rainfall commencing several decades ago, particularly for trees growing in deep sandy soils and (3) reduced groundwater availability that commenced well before 2003. Dieback was most likely to be associated with insect attack. Within the study region, pink gums occupy a wide gradient of rainfall, soil type and topography. A regional survey between 2009 and 2012 recorded that the mean canopy intactness for 2814 pink gums was 70%, but canopy condition varied widely between, and often within, pink gum woodlands. The habitat variables that contributed most to variation in canopy intactness were mistletoe prevalence, followed by insect damage. In almost 30% of populations there were no seedling pink gums. Between 2009 and 2011, mean canopy intactness of 1751 pink gums declined from 71% to 66%, 21 pink gums died, and no recruitment was recorded. Leaf production in pink gums was greatest during the above-average rainfall in the summer of 2010/11. This was followed by localised high levels of gum leaf skeletoniser (Uraba lugens) and lerp (Cardiaspina densitexta). Canopy loss from these insects was concluded to be cyclic and short term. The canopy intactness of 161 pink gums and their mistletoe load, was recorded between 2003 and 2015. The net number of live mistletoes declined by two thirds, with the greatest net decline occurring during three consecutive below-average rainfall years. While the mean canopy intactness of pink gums was the same in 2003 and 2015, pink gums whose canopy comprised at least 20% mistletoe, recorded significant canopy loss during consecutive years of below-average rainfall. Comparison of aerial photographs between 1949 and 2005 for two pink gum woodlands indicated that canopy decline began in the mid-1970s, coinciding with lowering of groundwater levels and increased mistletoe infection, and the beginning of an ongoing decline in autumn rainfall. These pink gums occurred on deep sands with approximately 500 mm annual rainfall, a habitat that would be more prone to autumn soil drying. Because of the lack of recent recruitment at many pink gum woodlands, it may be necessary to restore and/or maintain populations with revegetation. A glasshouse experiment involving manipulating water supply to three pink gum provenances showed that there was genetic variation between provenances. This will provide the option in revegetation projects, of matching selection of seed sources to projected climate change. However, in a separate six year study, 12 of 34 pink gum juveniles remained the same height, with insect defoliators and competition from nearby trees considered largely responsible for suppressing growth. The potential slow growth rate of pink gums should be incorporated into revegetation planning. This study provided evidence that pink gums may be at least partially groundwater dependent. Within the same woodland, where all habitat factors other than depth to groundwater appeared to be equal, pink gums sited over shallower groundwater tables were significantly taller and had greater canopy volumes. A key finding was that pink gums occurring on deep sands with moderate mean annual rainfall for the study region and with high mistletoe loads, had low canopy intactness. Areas of future research should focus on: which populations of pink gums are at least partially groundwater dependent; the interaction between pink gum water stress and mistletoe abundance over long time frames; and differences between pink gum provenances in drought response and growth rates. Future monitoring of survey sites established in this study would provide information on pink gum canopy and population trends, and mistletoe population trends.
Thesis (Ph.D.) -- University of Adelaide, School of Biological Sciences, 2017.
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17

Hammerli, Johannes. "Using microanalysis of minerals to track geochemical processes during metamorphism: examples from the Mary Kathleen fold belt, Queensland, and the Eastern Mt. Lofty Ranges, South Australia." Thesis, 2014. https://researchonline.jcu.edu.au/39966/1/39966-hammerli-2014-thesis.pdf.

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Understanding the behaviour of major and trace elements during metamorphism is fundamental for our understanding of the geochemical evolution of the Earth's crust and the formation of orogenic orebodies. Furthermore, it is essential to know how key elements and radiogenic isotopes behave in metamorphic/hydrothermal systems in order to apply them meaningfully to solve important questions in geosciences. Metamorphic/hydrothermal reactions are most evidently preserved at the mineral scale, so in situ microanalytical techniques are best suited for tracing the record of metamorphism or hydrothermal alteration. In this thesis, I outline new analytical developments for in situ analysis of halogens in minerals and fluid samples, and of Sm-Nd isotopes in REE-rich minerals. These techniques, in conjunction with comprehensive bulk rock and mineral geochemistry and element distribution analysis, are then applied to well-characterised metamorphic rocks from the Adelaide Fold Belt and Mt Isa Inlier. Although fluid is an essential ingredient for mass transport during metamorphism, it is often difficult to identify the source of metamorphic/hydrothermal fluids. Traditionally, fluid inclusions have been used to gain insights into the source and composition of fluids. Until very recently, quantification of key elements such as bromine and chlorine in fluid inclusions relied almost solely on bulk rock analyses techniques (i.e., crush-leach). These methods do not allow distinction between different fluid inclusion generations that might hold crucial information on the evolution of a hydrothermal system and associated mineralization. The development of in situ LA-ICP-MS analysis of chlorine and bromine in fluid inclusions now allows for the targeting of individual fluid inclusions of a specific fluid type in a mineral. In this thesis these techniques were further tested and refined, and applied for the first time to a range of natural scapolite group minerals, minerals assumed to reflect the Cl/Br content of the coexisting hydrothermal fluids. The results show that fluid sources can be identified with a ~ 25 μm resolution in Cl and Br bearing minerals. This technique was applied on scapolite minerals from skarns, regional metamorphic rocks and a mineralized shear-zone of the Mary Kathleen Fold Belt in the Mt. Isa inlier. While scapolite minerals in skarns contain Cl/Br ratios typically associated with granitic fluids, metamorphic scapolite indicates that fluids were dominantly derived from basinal brines formed from sub-aerial evaporation of seawater beyond the point of halite saturation. This bittern fluid infiltrated the underlying sedimentary sequences prior to regional metamorphism. Zoned scapolite in the mineralized shear-zone records three discrete pulses of magmatic and metamorphic fluid, and it is suggested that fluid mixing may have assisted mineralization along and around this shear-zone. To investigate element mobility during metamorphism, I studied the Eastern Mt. Lofty Ranges in South Australia. Metamorphic rocks of the Mt. Lofty Ranges have a relatively simple metamorphic history, and metamorphic gradients and widespread up-temperature fluid flow has been documented previously. This allows monitoring of mineral and bulk rock compositional changes (or lack thereof) during metamorphism across a regional metamorphic gradient from ~350–400 ˚C to migmatite grade (~ 650–700 ˚C) at ~0.3–0.5 GPa, in a confined framework. The results show that, despite widespread up-temperature fluid flow, major elements and most trace elements are isochemical during metamorphism. These elements are effectively redistributed into newly formed major minerals or accessory phases. Monazite or allanite and xenotime control the whole rock concentration of REE whereas apatite and titanite are minor REEs hosts. The only non-volatile mobile elements are Zn, Pb, Cs and As whose concentrations decreased with increasing metamorphic grade. The Zn and Pb depletion was progressive with increasing temperature in staurolite-absent psammo-pelites, with losses of ~ 75% of the original Zn and ~ 50 % of the original Pb from the rocks from high-grade metamorphic zones. Microanalysis showed that biotite is a key mineral for Zn sequestration by concentrating >80 % of the Zn in the bulk rock. Zinc and Pb likely partitioned into a Cl-rich hydrothermal/metamorphic fluid that led to the observed depletion of Pb and Zn in the bulk rock. Simple mass balance calculations show that ~27 Mt of Zn and ~2.7 Mt of Pb were mobilized during prograde metamorphism, which is comparable to the amounts of base metals found in world class Pb-Zn deposits. Hence, prograde metamorphism of sedimentary rock packages is a viable base metal source for the formation of some Pb-Zn deposits, provided that the metamorphic fluid contains sufficient Cl to effectively mobilise metals from the metamorphic system into ore-forming environments. The observed As loss is consistent with the recrystallization of As-bearing pyrite to As-poor pyrrhotite, confirming previous studies. Cesium depletion in migmatites can be explained by the incompatibly of Cs in micas in high-grade metamorphic rocks. Significant element mobility during metamorphism is likely only achieved under conditions with high fluid flux. In order to understand crustal evolutionary processes and crustal fractionation via for example melt production in migmatitic systems equivalent to the high-grade zone of the Eastern Mt. Lofty Ranges, geochemists widely rely on radiogenic isotopes. However recent claims of Nd and Sr isotope disequilibrium during anatexis question the reliability radiogenic isotopes. Microanalysis of REE-rich accessory minerals was used to investigate Nd isotope equilibration during metamorphism in order to assess to potential of disequilibrium situations during high-grade metamorphism. The results are used to demonstrate that apatite retains an original, probably detrital, highly variable Nd isotopic signature until at least 500 ˚C, before being isotopically homogenized. In contrast, allanite and titanite are equilibrated at temperatures as low as 350–400 ˚C. REE-rich accessory minerals in high-grade rocks (~600 ˚C) show very similar initial Nd isotope values at the time of metamorphism. I conclude that Nd isotope disequilibrium between crustal melts and metasedimentary sources is unlikely. Furthermore, in situ microanalysis of radiogenic isotopes can help to identify external melt components in migmatites that would not be resolvable by conventional bulk rock analysis.
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