Dissertationen zum Thema „Soil management South Australia“
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1
Hawkes, N. J. „Spring dead spot in tifdwarf turf, South Australia /“. Title page, contents and summary only, 1986. http://web4.library.adelaide.edu.au/theses/09A/09ah392.pdf.
2
Crawford, Michael Cameron. „Quantification of the belowground inputs of organic carbon by the annual pasture legume barrel medic (Medicago truncatula Gaertn.)“. Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phc8988.pdf.
Annotation:
Bibliography: leaves 164-193. This study aims to quantify the belowground input of organic carbon by barrel medic using techniques that account for root death and decomposition as well as root secretion and exudation. It also investigates the effect of defoliation on carbon allocation within the plant so as to determine the potential for optimising carbon input to the soil through grazing management.
3
Horsnell, Tara Kathleen. „Quantifying thresholds for native vegetation to salinity and waterlogging for the design of direct conservation approaches“. University of Western Australia. School of Environmental Systems Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0082.
Annotation:
A field-based project was undertaken to develop and test a mechanism which would allow for the correlation of the health of vegetation surrounding playa lakes in south-west Australia with the natural variation in salinity and waterlogging that occurs spatially and temporally in natural systems. The study was designed to determine threshold ranges of vegetation communities using moderately extensive data over short temporal periods which will guide the design of potential engineering solutions that manipulate hydrological regimes to ultimately conserve and protect native vegetation. A pair of playa lake ecosystems, surrounded by primary production land, was modelled with hydro-geological data collected from March 2006 to March 2007. The data was used to determine the hydroperiods of vegetation communities fringing playa lakes and provide insight into the areas and species that are most affected by extreme rainfall events which are hypothesised to have a significant, rapid deleterious effect on the ecosystems. The methodology was multi-faceted and included; a detailed topographical survey; vegetation surveys; hydrological and hydro-geological monitoring over a 12 month period. 4 The hydro-geological data and vegetation data was linked with the topographical survey at a high resolution for spatial analysis in a Geographic Information System (GIS) to determine the degree of waterlogging experienced by vegetation communities over the monitoring period. The study has found that the spatial and temporal variability of hydroperiods has been reduced by rising groundwater levels, a result of extensive clearing of native vegetation. Consequently populations are becoming extinct locally resulting in a shift in community composition. Extreme summer rainfall events also have a significant impact on the health of vegetation communities by increasing the duration of waterlogging over an annual cycle and in some areas expanding the littoral zone. Vegetation is most degraded at lower positions in the landscape where communities are becoming less diverse and dominated by salt tolerant halophytic species as a result of altered hydrological regimes. Some species appear to be able to tolerate groundwater depths of less than 2.0 m from the surface, however there are thresholds related to the duration at which groundwater is maintained at this depth. Potential engineering solutions include groundwater pumping and diverting water through drains to maintain sustainable hydroperiods for vegetation in areas with conservation value. The effectiveness and efficiency of the engineering solutions can be maximised by quantifying thresholds for vegetation that include sustainable durations of waterlogging. The study has quantified tolerance ranges to salinity and waterlogging with data collected over 12 months but species may be experiencing a transition period where they have 5 sustained irreversible damage that will result in their eventual mortality. With long-term monitoring, the methodology developed and tested in the study can be used to quantify the long-term tolerance ranges that are important for the application of conservation approaches that include engineering solutions.
4
Harris, Mark Anglin. „Some organic amendments for heavy metal toxicity, acidity and soil structure in acid-sulphate mine tailings /“. Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phh3148.pdf.
5
Dexter, Anthony Roger. „Soil mechanical properties and the behaviour of roots in structured soil : published works“. Title page, contents and introduction only, 1988. http://web4.library.adelaide.edu.au/theses/09SD/09sdd526.pdf.
6
Odeh, Inakwu Ominyi Akots. „Soil pattern recognition in a South Australian subcatchment /“. Title page, contents and abstract only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09pho23.pdf.
7
Esfandiari, Baiat Mansour, of Western Sydney Hawkesbury University, of Science Technology and Agriculture Faculty und School of Agriculture and Rural Development. „Evaluation of furrow irrigation models for south-east Australia“. THESIS_FSTA_ARD_EsfandiariBaiat_M.xml, 1997. http://handle.uws.edu.au:8081/1959.7/739.
Annotation:
The overall objective of this study was to evaluate the performance of selected furrow irrigation models for field conditions in south-east Australia. The other important aspects which were examined during this study include: developing a methodology for estimating of infiltrating characteristics, assessing the applicability of the Manning and other similar equations for flows in furrow irrigation, investigating the variation of shape factor during irrigation developing methodology for estimation of recession time and exploring the sensitivity of the models to the input parameters. Field experiments were conducted at Walla Park in northern N.S.W. and on two selected paddocks at the University Farm, Richmond, in western Sydney,Australia, over a period of three years. The validity of the assumption that the shape factor of advancing water front during furrow irrigation varies between 0.7 and 0.8 was investigated using field data collected from irrigation events monitored in the study. It was found that the average values of the shape factor varied from 0.96 to 1.80 at Walla Park site, from 0.56 to 0.80 at Field Services unit paddock site and from 0.78 to 0.84 at Horticulture Farm paddock site. The value of shape factor was affected by uniformity of furrow cross section along the length, the value and uniformity of furrow slope, furrow length and infiltration characteristics of soil. This means it is difficult to recommend a typical value for the shape factor for a given field situation.The performance of the models for prediction of advance and recession characteristics and runoff were evaluated using different indices of performance. In general, it was found that the Walker-HD and ZI model was the most satisfactory for the field conditions encountered in this study. This finding can provide a basis for initiating work on developing design criteria and management strategies for furrow irrigation in south-east Australia.Doctor of Philosophy (PhD)
8
Heshmatti, Gholam Ali. „Plant and soil indicators for detecting zones around water points in arid perennial chenopod shrublands of South Australia /“. Title page, contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phh584.pdf.
Annotation:
Thesis (Ph. D.)--University of Adelaide, Dept. of Botany, 1997.Errata page is behind title page (p. i). Copies of author's previously published articles inserted. Includes bibliographical references (leaves 121-156).
9
Brooke, Cassandra. „Marine pollution management under the Environment Protection Act 1993 (SA) /“. Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09ENV/09envb872.pdf.
10
Biddle, Dean Leslie. „Investigation of water-mineral interactions in gneissic terrain at Mt. Crawford, South Australia“. Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phb584.pdf.
Annotation:
Diskette for IBM/PC in pocket on back end paper. Copies of author's previously published articles inserted. Bibliography: leaves 186-207. An evaluation of spatial and temporal variation in composition of soil solutions collected from a hydro-toposequence with seasonally saturated soils ranging from Xeralfs to Aqualfs. The sub-catchment is under native eucalyptus and is formed from granite gneiss. The study shows that mineral weathering under eucalypt vegetation contributes substantially to the quantity of elements measured in soil solution with some aeolian salts. Migration of soil solutions to low lying areas promotes dryland salinity in these landscapes.
11
Pritchard, Deborah Leeanne. „Phosphorus bioavailability from land-applied biosolids in south-western Australia“. Curtin University of Technology, Muresk Institute, 2005. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=16492.
Annotation:
The annual production of biosolids in the Perth region during the period of this study was approximately 13,800 t dry solids (DS), being supplied by three major wastewater treatment plants. Of this, 70% was typically used as a low-grade fertiliser in agriculture, representing an annual land use area of around 1,600 ha when spread between 5 and 7 t DS/ha. Loading rates of biosolids are typically based on the nitrogen (N) requirements of the crop to be grown, referred to as the N Limiting Biosolids Application Rate (NLBAR). A consequence of using the NLBAR to calculate loading rates is that phosphorus (P) is typically in excess of plant requirement. The resultant high loading rates of P are considered in the guidelines developed for the agricultural use of biosolids in Western Australia, but lack research data specific to local conditions and soil types. Regulatory changes throughout Australia and globally to protect the environment from wastewater pollution have created a need for more accountable and balanced nutrient data. Experiments presented in this thesis were undertaken to ascertain: the percentage relative effectiveness (RE) of biosolids as a source of plant available P compared with inorganic P fertiliser; loading rates to best supply P for optimum crop growth; P loading rates of risk to the environment; and the forms of P in local biosolids. Therefore, both the agronomic and environmental viewpoints were considered. Anaerobically digested and dewatered biosolids produced from Beenyup Wastewater Treatment Plant, Perth with a mean total P content of 2.97% dry weight basis (db) were used in a series of glasshouse, field and laboratory experiments. The biosolids were sequentially fractionated to identify the forms of P present and likewise in soil samples after applying biosolids or monocalcium phosphate (MCP).The biosolid P was predominantly inorganic (92%), and hence the organic fraction (8%) available for mineralisation at all times would be extremely low. The most common forms of biosolid P were water-soluble P and exchangeable inorganic P (66%), followed by bicarbonate extractable P (19%) and the remaining P as inorganic forms associated with Fe, Al and Ca (14%). Following the application of biosolids to a lateritic soil, the Fe and Al soil fractions sorbed large amounts of P, not unlike the distribution of P following the addition of MCP. Further investigation would be required to trace the cycling of biosolid P in the various soil pools. The growth response of wheat (Triticum aestivum L.) to increasing rates of biosolids and comparable rates of inorganic P as MCP, to a maximum of 150 mg P/kg soil was examined in the glasshouse. The percentage relative effectiveness (RE) of biosolids was calculated using fitted curve coefficients from the Mitscherlich equation: y = a (1-b exp–cx) for dry matter (DM) production and P uptake. The initial effectiveness of biosolid P was comparable to that of MCP with the percentage RE of biosolids averaging 106% for DM production of wheat shoots and 118% for shoot P uptake at 33 days after sowing (DAS) over three consecutive crops. The percentage residual value (RV) declined at similar rates for DM production in MCP and biosolids, decreasing to about 33% relative to freshly applied MCP in the second crop and to approximately 16% in the third crop. The effectiveness of biosolid P was reduced significantly compared with inorganic P when applied to a field site 80 km east of Perth (520 mm annual rainfall). An infertile lateritic podsolic soil, consistent with the glasshouse experiment and representative of a soil type typically used for the agricultural application of biosolids in Western Australia was used.
Increasing rates of biosolids and comparable rates of triple superphosphate (TSP), to a maximum of 145 kg P/ha were applied to determine a P response curve. The percentage RE was calculated for seasonal DM production, final grain yield and P uptake in wheat followed by lupin (Lupinus angustifolius L.) rotation for the 2001 and 2002 growing seasons, respectively. In the first year of wheat, the RE for P uptake in biosolids compared with top-dressed TSP ranged from 33% to 55% over the season and by grain harvest was 67%. In the second year, and following incorporation with the disc plough at seeding, the RE for P uptake by lupins in biosolids averaged 79% over the growing season compared with top-dressed TSP, and by grain harvest the RE was 60%. The residual value (RV) of lupins at harvest in biosolids compared with freshly applied TSP was 47%. The non-uniform placement of biosolids (i.e. spatial heterogeneity) was primarily responsible for the decreased ability of plant roots to absorb P. The P was more effective where biosolids were finely dispersed throughout the soil, less so when roughly cultivated and least effective when placed on the soil surface without incorporation. The RE for grain harvest of wheat in the field decreased from 67% to 39% where biosolids were not incorporated (i.e. surface-applied). The RE could also be modified by factors such as soil moisture and N availability in the field, although it was possible to keep these variables constant in the glasshouse. Consequently, absolute values determined for the RE need to be treated judiciously. Calculations showed that typical loading rates of biosolids required to satisfy agronomic P requirements of wheat in Western Australia in the first season could vary from 0 to 8.1 t DS/ha, depending on soil factors such as the P Retention Index (PRI) and bicarbonate available P value.
Loading rates of biosolids were inadequate for optimum P uptake by wheat at 5 t DS/ha (i.e. 145 kg P/ha) based on the NLBAR on high P sorbing soils with a low fertiliser history (i.e. PRI >15, Colwell bicarbonate extractable P <15 mg P/kg). On soils of PRI <2 mL/g however, biosolids applied at identical loading rates would result in high concentrations of available P. Further work on sites not P deficient would be necessary to validate these findings on farmed soils with a regular history of P fertiliser. The sieving of soil samples used in the field experiment to remove stones and coarse organic matter prior to chemical analysis inadvertently discarded biosolids particles >2 mm, and thus their was little relationship between soil bicarbonate extractable P and P uptake by plants in the field. The risk of P leaching in biosolids-amended soil was examined over a number of different soil types at comparable rates of P at 140 mg P/kg (as either biosolids or MCP) in a laboratory experiment. Given that biosolids are restricted on sites prone to water erosion, the study focussed on the movement of water-soluble P by leaching rather than by runoff of water-soluble P and particulate P. In general the percentage soluble reactive P recovered was lower in soils treated with biosolids than with MCP, as measured in leachate collected using a reverse soil leachate unit. This was particularly evident in acid washed sand with SRP measuring 14% for biosolids and 71% for MCP, respectively, although the differences were not as large in typical agricultural soils. Specific soil properties, such as the PRI, pH, organic carbon and reactive Fe content were negatively correlated to soluble reactive P in leachate and thus reduced the risk of P leaching in biosolids-amended soil.
Conversely, the total P and bicarbonate extractable P status of the soils investigated were unreliable indicators as to the amount of P leached. On the basis of the experiments conducted, soils in Western Australia were categorised according to their ability to minimise P enrichment and provide P necessary for crop growth at loading rates determined by the NLBAR. Biosolids applied at the NLBAR to soils of PRI >2mL/g with reactive Fe >200 mg/kg were unlikely to necessitate P loading restrictions. Although specific to anaerobically digested biosolids cake applied to Western Australian soils, the results will be of relevance to any industry involved in the land application of biosolids, to prevent P contamination in water bodies and to make better use of P in crop production.
12
Jayaswal, Shanti. „The geostatistical study of soil parameters for properties near Loxton, Riverland, South Australia /“. Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09SB/09sbj42.pdf.
13
Hood, Malcolm. „Coastal management in the District Council of Willunga South Australia“. Adelaide : University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1995. http://web4.library.adelaide.edu.au/theses/09ENV/09envh777.pdf.
14
Swarts, Derek Juan. „Soil community structure and litter decomposition under irrigated Eucalyptus Globulus in South Western Australia“. Connect to thesis, 2006. http://portal.ecu.edu.au/adt-public/adt-ECU2006.0051.html.
15
Hunter, David, und n/a. „Conservation Management of Two Threatened Frog Species in South-Eastern New South Wales, Australia“. University of Canberra. Applied Science, 2007. http://erl.canberra.edu.au./public/adt-AUC20081020.142239.
Annotation:
The decline and extinction of amphibian species over the past three decades is widely acknowledged as one of the greatest biodiversity crises of modem time. Providing convincing data to support hypotheses about these declines has proved difficult, which has greatly restricted the development and implementation of management actions that may prevent further amphibian declines and extinctions from occurring. In this thesis, I present research that was undertaken as part of the recovery programs for the southern corroboree frog (Pseudophryne corroboree), and the Booroolong frog (Litoria booroolongensis); two species that underwent very rapid declines in distribution and abundance during the 1980's. More specifically, I investigated potential causal factors in the declines of both species using experimental and correlative studies, and examined the mechanisms by which one threatening process (chytridiomycosis) may be causing continued decline and extinction in P. corroboree. I also examined the implications of population dynamics for monitoring L. booroolongensis, and suggest a possible monitoring strategy that may reliably facilitate the implementation of recovery objectives for this species. I also tested one possible reintroduction technique aimed at preventing the continued decline and extinction of P. corroboree populations.
In Chapters 2 and 3, I present the results from a series of experiments in artificial enclosures designed to examine whether the tadpoles of L. booroolongensis are susceptible to predation by co-occurring introduced predatory fish species; brown trout (Salmo trutta), rainbow trout (Oncorhynchus mykiss), European carp (Cyprinus carpio), redfin perch (Percafluviatilis), and mosquito fish (Gambusia holbrooki). I demonstrated that the tadpoles of L. booroolongensis, and a closely related species Litoria lesueuri, were palatable to non-native trout species, but not to two native predatory fish species, Gadopsis bispinosus and Galaxias olidus. A pond breeding frog species included in this experiment, Limnodynastes tasmaniensis, was palatable to both the native and non-native fish species. In a separate experiment I also demonstrated that the tadpole of L. booroolongensis is palatable to the three other introduced fish species examined in this study; C. carpio, P. fluviatilis, and G. holbrooki. In three of the experiments, the provision of rock within enclosures as a potential refuge habitat did not afford protection to L. booroolongensis tadpoles from
predation by any of the five introduced fish species examined. While all the introduced fish species tested here did consume L. booroolongensis tadpoles, the results also suggested that chemical unpalatability might afford some level of protection against some of these fish species. Firstly, the addition of alternative prey items in one of the experiments reduced the proportion of tadpoles consumed, suggesting that L. booroolongensis may not be a preferred prey item. Secondly, the proportion of tadpoles consumed varied greatly among the different fish species examined, suggesting differing levels of palatability. Overall, this study supports previous research in suggesting that chemical unpalatability may be an important strategy for the tadpoles of riverine frog species in south-eastern Australia to avoid predation by native fish species, and that this strategy is less effective against introduced fish species. While L. booroolongensis currently persists in streams inhabited by a number of introduced fish species, this study supports the likelihood that these species are having a negative impact on populations of L. booroolongensis in the wild.
In Chapter 4, I present the results of a study aimed at examining potential monitoring techniques for L. booroolongensis. The results of a mark-recapture exercise demonstrated that L. booroolongensis may exhibit large fluctuations in abundance from one year to the next, and through a prospective power analysis approach, I demonstrated that it would be difficult to confidently identify population trends of interest using either indices or estimates of abundance for this species. An assessment of the capacity to identify the presence or absence of L. booroolongensis using nighttime
spotlight surveys demonstrated the high detectability of this species using this technique, at both the scale of 300-meter sections of stream and individual breeding areas (typically less than 10-meters of stream). This study suggests that the monitoring objectives of the L. booroolongensis recovery program would be most effectively achieved using presence/absence surveys at different scales.
In Chapter 5, I present the results of a field survey aimed at determining the current distribution and habitat requirements of L. booroolongensis in the South West Slopes region of New South Wales. Of the 163 sites I surveyed across 49 streams,I located
L. booroolongensis along 77 of these sites from 27 streams. Based on population and habitat connectivity, this study identified 18 populations of L. booroolongensis that
are likely to be operating as independent populations. Twelve of these populations are not represented in conservation reserves, but rather occur along streams that flow through the agricultural landscape. A broad scale habitat analysis identified a positive relationship between extent of rock structures along the stream and the occurrence of
L. booroolongensis, and a negative relationship between the proportion of canopy cover and this species' occurrence. At the breeding habitat scale, this study identified a positive relationship between the presence of breeding males and; number of rock crevices in the aquatic environment, extent of emergent rocks, and proportion pool. This analysis also detected a negative relationship between occupancy and water depth. These results confirm previous work suggesting the importance of rocky stream habitats to the persistence of L. booroolongensis, but also suggest how disturbance processes, such as increasing sedimentation and weed invasion, may reduce the suitability of rocky structures as breeding sites.
In Chapter 6, I investigated current levels of amphibian chytrid fungus (Batrachochytrium dendrobatidis) infection in corroboree frog populations, and used retrospective screening of museum specimens to assess the possibility that this pathogen was implicated in the initial decline of the corroboree frogs. Using histology, I did not detect any B. dendrobatidis infections in corroboree frog populations prior to their decline, however using the same technique, moderate levels of infection were detected in post-decline populations of both species. Real-time PCR screening of skin swabs identified much higher overall infection rates in post-decline populations of P. corroboree (between 44% and 59%), while significantly lower rates of infection were observed in P. pengilleyi populations (14%). These results suggest that the initial and continued decline of the corroboree frogs may well be attributed to the emergence of B. dendrobatidis in populations of these species.
In Chapter 7, I investigated how B. dendrobatidis may be causing the continued decline of P. corroboree through the presence of an abundant reservoir host for this pathogen. I found that populations of adult C. signifera in sub-alpine bogs carry high
B. dendrobatidis infection rates (86%), but appear unaffected by this infection. An experiment involving the release of P. corroboree tadpoles into 15 natural pools resulted in metamorphs from seven of these pools testing positive for B. dendrobatidis, with all these individuals dying soon after metamorphosis. These
results support the possibility that B. dendrobatidis infection in P. corroboree populations is being facilitated by the presence of large numbers of infected C. signifera in the shared environment.
Chapter 8 presents the results of a population augmentation study for P. corroboree. I investigated the extent to which increasing recruitment to metamorphosis may result in population recovery in this species. This was undertaken by harvesting eggs from the field and rearing them through to mid stage tadpoles over the winter period prior to being released back to their natal ponds in spring. While I was able to increase recruitment to metamorphosis by an average of 20 percent, this did not result in a noticeable influence on the subsequent adult population size, as both manipulated and non-manipulated sites declined over the course of this study by an average of 80 percent. I observed a positive relationship between natural recruitment to a late tadpole stage and subsequent adult male population size, however there was considerable variation associated with this relationship. The relationship between recruitment and subsequent population size at the augmentation sites was consistent with the relationship observed at the non-manipulated sites. These results suggest that recruitment to metamorphosis may not be the most important life stage restricting the population recovery of P. corroboree, but that mortality during post-metamorphic stages may be more important in regulating current population size. Hence, further attempts to use captive rearing to increase P. corroboree populations in the wild should focus on the release of post-metamorphic frogs.
Overall, this thesis demonstrates the value of quantitative research to the implementation and progress of threatened species recovery programs. While this research will specifically contribute to the recovery programs for L. booroolongensis
and P. corroboree, it more broadly contributes to the understanding and capacity to respond to the concerning levels of amphibian extinctions currently occurring throughout the world.
16
Hunter, David. „Conservation management of two threatened frog species in South-Eastern New South Wales, Australia /“. full text via ADT, 2007. http://erl.canberra.edu.au/public/adt-AUC20081020.142239/index.html.
17
Reeve, Martin. „Fragmented landscape and fragmented law : threatened species management in South Australia /“. Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09ENV/09envr331.pdf.
18
Gauvin, Clea. „Controlling space : management of Torrens Title in South Australia and overseas /“. Title page, table of contents and introduction only, 1997. http://web4.library.adelaide.edu.au/theses/09ISG/09isgg277.pdf.
19
Kupke, Valerie. „Local Agenda 21 : integrated environmental management by local government in South Australia /“. Title page, table of contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09ENV/09envk96.pdf.
20
Clarke, Beverly Dawn. „Aquaculture management & planning in South Australia : blue farming revolution or goldrush? /“. Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09ENV/09envc597.pdf.
21
Sunohara, Mark Douglas. „Soil microstructure and soil erodibility at IBSRAM Sloping Lands management sites in south-east Asia“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ36876.pdf.
22
Sun, Hua. „Digital terrain modelling of catchment erosion and sedimentation /“. Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phs9565.pdf.
23
Szota, Christopher. „Root morphology, photosynthesis, water relations and development of jarrah (Eucalyptus marginata) in response to soil constraints at restores bauxite mines in south-western Australia“. University of Western Australia. School of Plant Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0058.
Annotation:
Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots. Bauxite mining is a major activity in the jarrah (Eucalyptus marginata Donn ex Sm.) forest of south-western Australia. After mining, poor tree growth can occur in some areas. This thesis aimed to determine whether soil constraints, including reduced depth and compaction, were responsible for poor tree growth at low-quality restored bauxite mines. In particular, this study determined the response of jarrah root morphology, leaf-scale physiology and growth/development to soil constraints at two contrasting (low-quality and high-quality) restored bauxite-mine sites. Jarrah root excavations at a low-quality restored site revealed that deep-ripping equipment failed to penetrate the cemented lateritic subsoil, causing coarse roots to be restricted to the top 0.5 m of the soil profile, resulting in fewer and smaller jarrah trees. An adjacent area within the same mine pit (high-quality site) had a kaolinitic clay subsoil, which coarse roots were able to penetrate to the average ripping depth of 1.5 m. Impenetrable subsoil prevented development of taproots at the low-quality site, with trees instead producing multiple lateral and sinker roots. Trees in riplines, made by deep-ripping, at the high-quality site accessed the subsoil via a major taproot, while those on crests developed large lateral and sinker roots.
24
James-Smith, Julianne Marie. „Development of a water management model for the evaluation of streamflow for aquifer storage and recovery“. Title page, contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09ENS/09ensj291.pdf.
Annotation:
Addendum on back page. Includes bibliography. Groundwater levels within the Willunga Basin, South Australia, are declining due to excessive extraction of water for irrigation purposes. An alternative source of water is needed to supplement the declining levels to ensure the sustainability of the groundwater system. A model was developed to evaluate the potential for using aquifer storage and recovery in conjunction with the surface storage of streamflow as a possible alternative water source. The application of this model to the largest catchment in the Willinga basin shows that sufficient streamflow is available to reverse the current overexploitation of the groundwater system.
25
Nguyen, Cao Nam. „Farming risks in the Upper Eyre Peninsula : AGRIC 7010 Project C (ANR) (one semester)“. Title page, table of contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09AGM/09agmn5764.pdf.
Annotation:
"November 2002." Bibliography: leaves 73-80. Identifies main sources of farming risk in the Upper Eyre Peninsula as climate variability and financial risk. Finds that farmers manage risk by having high equity and off-farm investment, using gross margin analysis, having farm management deposits, diversifying varieties, minimizing tillage, relying on experts for grain marketing and keeping stock for high price periods.
26
Norrish, Shane A., University of Western Sydney, of Science Technology and Environment College und School of Environment and Agriculture. „Soil and water interactions controlling wheat crop response to phosphorus fertiliser in north-western New South Wales“. THESIS_CSTE_EAG_Norrish_S.xml, 2003. http://handle.uws.edu.au:8081/1959.7/613.
Annotation:
This thesis examines the response to P fertiliser by wheat crops growing in the vertosol soils of the low rainfall areas of the northern grain zone of eastern Australia. Farmers in this region depend on water accumulated from rainfall over a fallow period and stored in the subsoil to increase wheat grain yield beyond that normally achievable from in-crop rainfall and to decrease the production risks due to rainfall variability. The large variability in stored water, seasonal rainfall and subsoil properties result in extremely varied yield and yield responses to P fertiliser between seasons and between sites. Finally, as a practical guide to predicting wheat response to P fertilizer: 1/. current sampling strategies of determining P only in the surface 10 cm appear to be adequate for soils with bicarbonate P concentrations greater than 15 mg/kg. 2/. For soils with lower concentrations in the surface, sampling of 80 cm is recommended. Crops with a mean concentration of bicarbonate P greater than 7 mg/kg between 10 - 80 cm are unlikely to respond to P fertiliser. 3/. No increase in profitable grain yield response was found for fertiliser applications greater than 10 kg P/ha.Doctor of Philosophy (PhD)
27
Conran, Leigh Garde. „Establishment vegetation patterns in an artificial urban wetland as a basis for management“. Title page, contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09ENV/09envc754.pdf.
28
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.
Annotation:
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.
29
Tiver, Fleur. „Vegetation patterns of eastern South Australia : edaphic control and effects of herbivory /“. Title page, contents and abstract only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09pht623.pdf.
30
Morgan, Karina School of Biological Earth & Environmental Sciences UNSW. „Evaluation of salinisation processes in the Spicers Creek catchment, central west region of New South Wales, Australia“. Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2005. http://handle.unsw.edu.au/1959.4/24327.
Annotation:
Spicers Creek catchment is located approximately 400 km west of Sydney in the Central West region of New South Wales, Australia. Dryland salinity has been recognised as a major environmental issue impacting soil and water resources in the Central West region of NSW for over 70 years. Due to the geological complexity of the catchment and the presence of high salt loads contained within the soils, groundwater and surface waters, the Spicers Creek catchment was identified as a large contributor of salinity to the Macquarie River catchment. Over fifty-two dryland salinity occurrences have been identified in the Spicers Creek catchment and it appears that dryland salinity is controlled by the presence of geological structures and permeability contrasts in the shallow aquifer system. Combinations of climatic, geological and agricultural factors are escalating salinity problems in the catchment. The main aim of this thesis was to identify the factors affecting salinisation processes in the Spicers Creek catchment. These include the role of geological structures, the source(s) of salts to the groundwater system and the geochemical processes influencing seepage zone development. To achieve these aims a multidisciplinary approach was untaken to understand the soils, geology, hydrogeology and hydrogeochemistry of the catchment. Investigative techniques employed in this project include the use of geophysics, soil chemistry, soil spectroscopy, hydrogeochemistry and environmental isotopes. Evaluation of high-resolution airborne magnetics data showed a major north-east to south-west trending shear zone. This structure dissects the catchment and several other minor faults were observed to be splays off this major structure. These structures were found to be conducive to groundwater flow and are influencing the groundwater chemistry in the fractured aquifer system. Two distinctive groundwater chemical types were identified in the catchment; the saline Na(Mg)-Cl-rich groundwaters associated with the fractured Oakdale Formation and the Na-HCO3-rich groundwaters associated with the intermediate groundwater system. The groundwater chemistry of other deep groundwaters in the catchment appears to be due to mixing between these end-member groundwaters within the fractured bedrock system. The spatial distribution of electrical conductivity, Cl-, Sr2+ and 87Sr/86Sr isotopic ratios showed the correlation between saline groundwaters and the location of faults. Elevated salinities were associated with the location of two crosscutting fault zones. The spatial distribution of HCO3-, K+, Li+ and ?????3CDIC highlighted the extent of Na-HCO3-rich groundwaters in the catchment and showed that these groundwaters are mixing further east than previously envisaged. These findings show that Na(Mg)-Cl-rich groundwaters are geochemically distinctive and have evolved due to extensive water-rock interaction processes within the fracture zones of the Oakdale Formation. These saline groundwaters contain elevated concentrations of trace elements such as As, V and Se, which pose a potential risk for water resources in the area. 87Sr/86Sr isotopic ratios indicated that the source of salinity to the Na(Mg)-Cl-rich groundwaters was not purely from marine or aerosol input. Salt is most likely contributed from various allochthonous and autochthonous sources. This research found that the main mechanism controlling the formation of dryland salinity seepage zones in the Spicers Creek catchment is due to the presence of geological structures. These groundwater seepage zones act as mixing zones for rainfall recharge and deeper groundwaters. The main sources of salt to the seepage zones are from deeper Na(Mg)-Cl-rich groundwaters and rainfall accession. The major importance of this research highlights the need for an integrated approach for the use of various geoscientific techniques in dryland salinity research within geologically complex environments.
31
Pudasaini, Madhu S., University of Western Sydney, of Science Technology and Environment College und School of Engineering and Industrial Design. „Erosion modelling under different land use management practices“. THESIS_CSTE_EID_Pudasaini_M.xml, 2003. http://handle.uws.edu.au:8081/1959.7/721.
Annotation:
Soil erosion has been recognised as a global threat against the sustainability of natural ecosystem. The work in this thesis has been undertaken to assist in combating this threat, and addresses the soil erosion issues associated with urban construction activities. The Revised Universal Soil Loss Equation (RUSLE) was employed in this research work and the parameters associated with the model were calibrated. This model was chosen for calibration, as it has been proven to be an easy to use tool yet providing reasonable results. Large scale rainfall simulators developed at UWS were used for rainfall simulation at two sites with diverse soil types: dispersive clayey soils at Penrith and highly permeable sandy soil at Somersby (Both in New South Wales, Australia). It is concluded that RUSLE can be successfully used in single storms for erosion prediction. Calibrated values of RUSLE parameters are useful in predicting soil erosion from the construction sites in NSW. It is also identified that in rolled smooth land condition, clayey soils are more erodible than sandy soil. Specific support practices such as short grass strips, gravel bags and silt fences are identified as very effective erosion control measures in reducing soil erosion from 45% to 85%. These results will be very useful in soil erosion prediction planning and conservation management in NSW.Master of Engineering (Hons)
32
com, rxysharma76@gmail, und Rajesh Sharma. „Soil and Landscape Factors Affecting Phosphorus Loss from the Fitzgerald River Catchment in South West of Western Australia“. Murdoch University, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20100331.90105.
Annotation:
Following over 100 years of agriculture and continuous phosphorus (P) fertilizer application in the south west of Western Australia, there is a growing risk of P transport from cropping and pasture land to streams. However, soil and landscape factors affecting the likelihood of P losses and of stream water contamination have not yet been assessed for the South coast region of Western Australia. The present investigation was conducted in the Fitzgerald River catchment located ~ 400 km south east of Perth, to identify risk of P losses from agricultural land to streams, through an understanding of how P is retained within complex landscapes and released via surface and subsurface flow paths. The 104,000 ha catchment is in a moderately dissected landscape (average annual rainfall 450 mm) and discharges into the World Heritage listed Fitzgerald Biosphere. The main use of cleared land in the catchment is broad-scale agriculture, primarily winter grain cropping and pasture for livestock.
The aim of an initial study was to identify the areas with high soil P concentrations and their relationship to factors such as soil type, topography, management (e.g. fertilizer and manure inputs, and uptake by crops or forage) and how variations in soil P concentrations were related to soil physico-chemical properties, P fertilizer management and landscape position. A wide variation in P concentrations was observed across the catchment, but few of the samples exceeded Colwell extractable P levels of 30 mg/kg in the 0-10 cm layer which is regarded as a critical level for crop and pasture productivity. The western area of the catchment, which was cleared earlier (before 1966) than the eastern area had a greater prevalence of loam soils, and higher Colwell-extractable P concentrations (average)22 mg/kg vs. 13 mg P/kg) due to soil type effects and higher P accumulation over time. Risk of P loss from the east and west of the catchment is expected to vary due to textural and topographic differences and P history (P fertilizer input and uptake by crops). The CaCl2-extractable P in the catchment was negatively correlated with oxalate extractable Fe (Feox) in soils. This suggests that P may be transported as particulate P (PP) on loam and clay soils due to sorption of P on oxides surfaces, while on sand soil leaching losses may be more likely. On loam and clay soils, higher sodicity and the dispersive nature of subsoils may increase the risk of both dissolved P (DP) and PP loss due to the effects on hydraulic conductivity of the profile.
Hedley's fractionation scheme was used to quantify P fractions in the order of decreasing lability, viz: resin-P > NaOH-Pi > NaOH-Po > acid-P (H2SO4-P) > residual-P. Surface soil had higher resin and NaOH-Pi, which are regarded as water-soluble and readily exchangeable P forms, respectively and expected to contribute to DP in the runoff losses. The residual P was the largest fraction followed by the hydroxide extractable organic-P fraction (NaOH-Po): the former was positively correlated (r) with clay content, organic carbon (OC) and pyrophosphate extractable Fe and Al (0.48**, 0.61**, 0.69** and 0.58**, P < 0.01). A relatively higher value of NaOH-Po in the subsurface layer and positive correlation with OC (r = 0.45**, P < 0.01) suggests potential mobility of P as soluble organic P in run-off, throughflow and leachate.
Phosphorus sorption and its relationship to soil properties was used to assess the potential P release from the catchment soils. Values of P sorption maxima varied from 1111-3333 mg/kg for surface soils and 1010-2917 mg/kg for subsoils. The P sorption isotherms conformed better to the Freundlich equation than the Langmuir equation. A highly significant negative correlation between CaCl2 extractable P and Feox in surface soils (r = -0.65**, P < 0.01) suggests that P was bound to hydrated Fe oxide surfaces and this may determine the concentration and dynamics of loosely bound P equilibrating with leachates and eroded particulate materials. On the other hand, high surface organic matter and the high proportion of total dissolved P in organically bound form may inhibit P sorption on clays and sesquioxides, which would increase P mobility through leaching or runoff losses.
The relationship between soil P concentration and degree of P stratification in the top 0-10 cm of soils along five toposequences was examined to predict the effect on runoff P losses. The total Colwell-P content of the 0-10 cm layer of soils in the catchment was very low in comparison to other studies on P losses from agricultural soils, but soils showed higher P concentration at 0-1 cm depth compared to 5-10 cm (average 37 mg/kg vs. 19 mg/kg). The higher extractable P concentration in the 0-1 cm layer will create a greater P mobilization risk in surface runoff and leachate than analysis of the 0-10 cm layer might suggest. Assessment of P risk using the 0-10 cm data would still be reliable as P concentration in the 0-1 cm layer was linearly related (R2 = 0.59) with concentration in the 0-10 cm layer. The sampling at varied soil depths will result in different critical P levels for estimating the risk of P enrichment in runoff.
In a glasshouse study with intact soil columns, initial high P concentrations in leachate decreased with leaching events suggesting that macropore flow dominated in initial leaching events changing later to matrix flow. The hydraulic behavior of clay and loam soil below 10 cm depends largely on structure and the type of clay minerals and exchangeable Na. Higher levels of exchangeable Na in the subsoil might increase dispersion of clay particles resulting in low permeability leading to ponding of surface water or lateral movement of water at the interface of sand A and clay B horizons. Lateral water movements increase the risk of P losses in the form of DP, dissolved organic P (DOP) or PP. The P concentration in all the P forms (DRP, DOP and TDP) increased significantly with P rates of application (P < 0.01). The DRP concentration was < 2 mg/l in unfertilized columns but an increase to 11 mg/l was observed with P application at 40 kg P/ha. The higher proportion of DOP relative to DRP and its correlation with TDP indicates that the DOP was the major form of P in leachate. However, the estimation of DOP which was by subtraction of DRP from TDP generally overestimates OP concentration.
The TDP load from unfertilized soil was < 0.20 mg/l in runoff and < 2.40 mg/l in throughflow but increased with P application (20, 40 kg P/ha) for both packed box and field studies. Under field conditions, higher P loss was found with broadcast P application compared to drill placement. The higher load of DOP as a proportion of TDP and its significant relationship with TDP in runoff (R2sand = 0.81; R2clay = 0.79) and throughflow (R2sand = 0.94; R2clay = 0.98) in field and box studies also suggests DOP was the major form of P loss from soil. Dissolved OP concentration increased significantly with increase in soluble organic carbon (SOC) in soil solution at 5 cm depth (P < 0.05). Consequently, the amount of organic matter dissolved in soil solution may influence P sorption and mobility. Relatively higher affinity of soil for sorption of DRP compared to DOP might allow DOP to be more mobile through the profile. Higher PP load in clay soil in throughflow indicates subsurface lateral flow along the interface with the horizon of dispersive clay might be an additional risk factor regarding P mobility in clay soils of the catchment.
The runoff, throughflow and leachate were dominated by eroded particles of clay and colloidal organic materials. However, the soil solution collected though 0.1 m pores in the Rhizon samplers had a similar dominance of DOP to the < 0.45 jum filtered samples in runoff and throughflow. This reduces the likelihood that the so-called DOP fraction was mostly P associated with PP in the 0.1 to 0.45 jum size fraction. The composition of DOP in soil solution collected through Rhizon samplers (< 0.1 jum) might provide important insights for P mobility since this more effectively excluded PP than in the < 0.45 jum filtrate used for runoff and throughflow samples. The DOP in soil solution (< 0.1 jum) might be associated with fine colloidal compound such as silicates, metallic hydroxides, humic acids, polysaccharides, fulvic acids and proteins. If so, then most, but not all of the DOP fraction would be organically bound. However, this requires verification.
In conclusion, soil P levels across the catchment were never very high when assessed in the 0-10 cm layer, but levels in the 0-1 cm layer were more than twice as high. Overall, < 1 % of land area of the upper Fitzgerald River catchment had Colwell-P levels > 30 mg/kg (0-10 cm) and hydrological connection to streams. In addition, another 7 % of land had Colwell-P levels > 15 mg/kg, which appears to be a change point in soils for the release of CaCl2 extractable P. These areas, which are predicted to represent critical source areas of the catchment, need careful management. The high proportions of TDP as DOP in runoff, throughflow and soil solution suggest DOP was the major form of P loss from soil. Phosphorus losses from the catchments are also likely in the form of PP in clay and loam soil but leaching losses are more likely in sand. High exchangeable Na in the subsoil of loam and clay soils increases dispersion of clay particles resulting in low permeability of subsoil and greater lateral P mobility as throughflow at the interface of sand and clay textured horizons.
In general, soils of Fitzgerald River catchment had low soil P, but nevertheless significant risk of P loss at Colwell-P > 15 mg/kg. This study provides baseline information for P loss risks in the wheatbelt of WA. Stream water quality monitoring instruments were installed in the upper Fitzgerald River Catchment at 5 stream locations by CSIRO to measure base line concentrations of P. The measured P concentrations were higher than ANZECC trigger values (> 0.05 mg P/l) for management response over the three-year monitoring period (2005-07). Hence this and many other catchments on the south coast and wheatbelt of south west Western Australia need assessment for P loss risks. Previous emphasis in south west Western Australia on P losses from sandy coastal soils under pasture may need to be reconsidered. In the South coast region, cropping land in the medium rainfall zone may still represent a risk of P loss to waterways and risk to water quality. The present study evaluated the risk of P loss based on soil P forms and their mobility. It suggests greater attention needs to be given to the difference between clay and loam soils with dispersive or non-dispersive sub-soils, and to the composition and mobility of DOP. However, a more complete understanding of P loss risks depends on follow-up studies on hydrological flow and connectivity in the upper Fitzgerald River catchment and similar landscapes of south west Western Australia.
33
Sharma, Rajesh. „Soil and Landscape Factors Affecting Phosphorus Loss from the Fitzgerald River Catchment in South West of Western Australia“. Sharma, Rajesh (2009) Soil and Landscape Factors Affecting Phosphorus Loss from the Fitzgerald River Catchment in South West of Western Australia. PhD thesis, Murdoch University, 2009. http://researchrepository.murdoch.edu.au/1690/.
Annotation:
Following over 100 years of agriculture and continuous phosphorus (P) fertilizer application in the south west of Western Australia, there is a growing risk of P transport from cropping and pasture land to streams. However, soil and landscape factors affecting the likelihood of P losses and of stream water contamination have not yet been assessed for the South coast region of Western Australia. The present investigation was conducted in the Fitzgerald River catchment located ~ 400 km south east of Perth, to identify risk of P losses from agricultural land to streams, through an understanding of how P is retained within complex landscapes and released via surface and subsurface flow paths. The 104,000 ha catchment is in a moderately dissected landscape (average annual rainfall 450 mm) and discharges into the World Heritage listed Fitzgerald Biosphere. The main use of cleared land in the catchment is broad-scale agriculture, primarily winter grain cropping and pasture for livestock.
The aim of an initial study was to identify the areas with high soil P concentrations and their relationship to factors such as soil type, topography, management (e.g. fertilizer and manure inputs, and uptake by crops or forage) and how variations in soil P concentrations were related to soil physico-chemical properties, P fertilizer management and landscape position. A wide variation in P concentrations was observed across the catchment, but few of the samples exceeded Colwell extractable P levels of 30 mg/kg in the 0-10 cm layer which is regarded as a critical level for crop and pasture productivity. The western area of the catchment, which was cleared earlier (before 1966) than the eastern area had a greater prevalence of loam soils, and higher Colwell-extractable P concentrations (average)22 mg/kg vs. 13 mg P/kg) due to soil type effects and higher P accumulation over time. Risk of P loss from the east and west of the catchment is expected to vary due to textural and topographic differences and P history (P fertilizer input and uptake by crops). The CaCl2-extractable P in the catchment was negatively correlated with oxalate extractable Fe (Feox) in soils. This suggests that P may be transported as particulate P (PP) on loam and clay soils due to sorption of P on oxides surfaces, while on sand soil leaching losses may be more likely. On loam and clay soils, higher sodicity and the dispersive nature of subsoils may increase the risk of both dissolved P (DP) and PP loss due to the effects on hydraulic conductivity of the profile.
Hedley's fractionation scheme was used to quantify P fractions in the order of decreasing lability, viz: resin-P > NaOH-Pi > NaOH-Po > acid-P (H2SO4-P) > residual-P. Surface soil had higher resin and NaOH-Pi, which are regarded as water-soluble and readily exchangeable P forms, respectively and expected to contribute to DP in the runoff losses. The residual P was the largest fraction followed by the hydroxide extractable organic-P fraction (NaOH-Po): the former was positively correlated (r) with clay content, organic carbon (OC) and pyrophosphate extractable Fe and Al (0.48**, 0.61**, 0.69** and 0.58**, P < 0.01). A relatively higher value of NaOH-Po in the subsurface layer and positive correlation with OC (r = 0.45**, P < 0.01) suggests potential mobility of P as soluble organic P in run-off, throughflow and leachate.
Phosphorus sorption and its relationship to soil properties was used to assess the potential P release from the catchment soils. Values of P sorption maxima varied from 1111-3333 mg/kg for surface soils and 1010-2917 mg/kg for subsoils. The P sorption isotherms conformed better to the Freundlich equation than the Langmuir equation. A highly significant negative correlation between CaCl2 extractable P and Feox in surface soils (r = -0.65**, P < 0.01) suggests that P was bound to hydrated Fe oxide surfaces and this may determine the concentration and dynamics of loosely bound P equilibrating with leachates and eroded particulate materials. On the other hand, high surface organic matter and the high proportion of total dissolved P in organically bound form may inhibit P sorption on clays and sesquioxides, which would increase P mobility through leaching or runoff losses.
The relationship between soil P concentration and degree of P stratification in the top 0-10 cm of soils along five toposequences was examined to predict the effect on runoff P losses. The total Colwell-P content of the 0-10 cm layer of soils in the catchment was very low in comparison to other studies on P losses from agricultural soils, but soils showed higher P concentration at 0-1 cm depth compared to 5-10 cm (average 37 mg/kg vs. 19 mg/kg). The higher extractable P concentration in the 0-1 cm layer will create a greater P mobilization risk in surface runoff and leachate than analysis of the 0-10 cm layer might suggest. Assessment of P risk using the 0-10 cm data would still be reliable as P concentration in the 0-1 cm layer was linearly related (R2 = 0.59) with concentration in the 0-10 cm layer. The sampling at varied soil depths will result in different critical P levels for estimating the risk of P enrichment in runoff.
In a glasshouse study with intact soil columns, initial high P concentrations in leachate decreased with leaching events suggesting that macropore flow dominated in initial leaching events changing later to matrix flow. The hydraulic behavior of clay and loam soil below 10 cm depends largely on structure and the type of clay minerals and exchangeable Na. Higher levels of exchangeable Na in the subsoil might increase dispersion of clay particles resulting in low permeability leading to ponding of surface water or lateral movement of water at the interface of sand A and clay B horizons. Lateral water movements increase the risk of P losses in the form of DP, dissolved organic P (DOP) or PP. The P concentration in all the P forms (DRP, DOP and TDP) increased significantly with P rates of application (P < 0.01). The DRP concentration was < 2 mg/l in unfertilized columns but an increase to 11 mg/l was observed with P application at 40 kg P/ha. The higher proportion of DOP relative to DRP and its correlation with TDP indicates that the DOP was the major form of P in leachate. However, the estimation of DOP which was by subtraction of DRP from TDP generally overestimates OP concentration.
The TDP load from unfertilized soil was < 0.20 mg/l in runoff and < 2.40 mg/l in throughflow but increased with P application (20, 40 kg P/ha) for both packed box and field studies. Under field conditions, higher P loss was found with broadcast P application compared to drill placement. The higher load of DOP as a proportion of TDP and its significant relationship with TDP in runoff (R2sand = 0.81; R2clay = 0.79) and throughflow (R2sand = 0.94; R2clay = 0.98) in field and box studies also suggests DOP was the major form of P loss from soil. Dissolved OP concentration increased significantly with increase in soluble organic carbon (SOC) in soil solution at 5 cm depth (P < 0.05). Consequently, the amount of organic matter dissolved in soil solution may influence P sorption and mobility. Relatively higher affinity of soil for sorption of DRP compared to DOP might allow DOP to be more mobile through the profile. Higher PP load in clay soil in throughflow indicates subsurface lateral flow along the interface with the horizon of dispersive clay might be an additional risk factor regarding P mobility in clay soils of the catchment.
The runoff, throughflow and leachate were dominated by eroded particles of clay and colloidal organic materials. However, the soil solution collected though 0.1 m pores in the Rhizon samplers had a similar dominance of DOP to the < 0.45 jum filtered samples in runoff and throughflow. This reduces the likelihood that the so-called DOP fraction was mostly P associated with PP in the 0.1 to 0.45 jum size fraction. The composition of DOP in soil solution collected through Rhizon samplers (< 0.1 jum) might provide important insights for P mobility since this more effectively excluded PP than in the < 0.45 jum filtrate used for runoff and throughflow samples. The DOP in soil solution (< 0.1 jum) might be associated with fine colloidal compound such as silicates, metallic hydroxides, humic acids, polysaccharides, fulvic acids and proteins. If so, then most, but not all of the DOP fraction would be organically bound. However, this requires verification.
In conclusion, soil P levels across the catchment were never very high when assessed in the 0-10 cm layer, but levels in the 0-1 cm layer were more than twice as high. Overall, < 1 % of land area of the upper Fitzgerald River catchment had Colwell-P levels > 30 mg/kg (0-10 cm) and hydrological connection to streams. In addition, another 7 % of land had Colwell-P levels > 15 mg/kg, which appears to be a change point in soils for the release of CaCl2 extractable P. These areas, which are predicted to represent critical source areas of the catchment, need careful management. The high proportions of TDP as DOP in runoff, throughflow and soil solution suggest DOP was the major form of P loss from soil. Phosphorus losses from the catchments are also likely in the form of PP in clay and loam soil but leaching losses are more likely in sand. High exchangeable Na in the subsoil of loam and clay soils increases dispersion of clay particles resulting in low permeability of subsoil and greater lateral P mobility as throughflow at the interface of sand and clay textured horizons.
In general, soils of Fitzgerald River catchment had low soil P, but nevertheless significant risk of P loss at Colwell-P > 15 mg/kg. This study provides baseline information for P loss risks in the wheatbelt of WA. Stream water quality monitoring instruments were installed in the upper Fitzgerald River Catchment at 5 stream locations by CSIRO to measure base line concentrations of P. The measured P concentrations were higher than ANZECC trigger values (> 0.05 mg P/l) for management response over the three-year monitoring period (2005-07). Hence this and many other catchments on the south coast and wheatbelt of south west Western Australia need assessment for P loss risks. Previous emphasis in south west Western Australia on P losses from sandy coastal soils under pasture may need to be reconsidered. In the South coast region, cropping land in the medium rainfall zone may still represent a risk of P loss to waterways and risk to water quality. The present study evaluated the risk of P loss based on soil P forms and their mobility. It suggests greater attention needs to be given to the difference between clay and loam soils with dispersive or non-dispersive sub-soils, and to the composition and mobility of DOP. However, a more complete understanding of P loss risks depends on follow-up studies on hydrological flow and connectivity in the upper Fitzgerald River catchment and similar landscapes of south west Western Australia.
34
Graham, Andrew. „Towards an integrated management approach for the common starling (Sturnus vulgaris) in South Australia /“. Title page, contents and introduction only, 1996. http://web4.library.adelaide.edu.au/theses/09SM/09smg738.pdf.
35
Chorom, Mostafa. „Behaviour of alkaline sodic soils and clays as influenced by pH and particle change“. Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phc551.pdf.
Annotation:
Copies of author's previously published articles inserted. Bibliography: leaves 173-196. The objective of this thesis is to investigate the factors affecting swelling and dispersion of alkaline sodic soils containing lime and the ways to manage these soils to improve their physical condition. Studies on pure clay systems are included to understand the fundamental process involved in swelling and dispersion of pure and soil clays.
36
Nobbs, J. M. „The distribution and abundance of nematodes (especially the plant parasites) in the arid region of South Australia /“. Title page, contents and summary only, 1987. http://web4.library.adelaide.edu.au/theses/09PH/09phn744.pdf.
37
Son, Vo Thanh, und n/a. „Evaluation of the USLE (Universal Soil Loss Equation) to estimate soil loss from hobby farms and commercial pastoral properties around Murrumbateman, NSW, Australia“. University of Canberra. Applied Science, 1993. http://erl.canberra.edu.au./public/adt-AUC20061108.171337.
Annotation:
This thesis is an evaluation of the use the USLE to estimate soil loss from
two pastoral land uses - commercial properties and "hobby farms" in
Murrumbateman. Sensitivity analysis was used to evaluate the USLE
components. Sediment measurement in farm dams was taken to estimate
sediment yield from several sites, as an alternative approach to study soil
loss. The annual soil loss from entire study area was 0.25 t/ha/year whilst
these figures from commercial properties and hobby farms were 0.29
t/ha/year and 0.21 t/ha/year, respectively. The annual average sediment
yield from three catchments in hobby farms was 0.3 t/ha/year. The USLE
was found to be highly sensitive to slope steepness, ground cover and
stocking rates. The critical values were 16% for slopes, 35% for the ground
cover and 19 Dry Sheep Equivalent/ha for stocking rate. I tentatively
conclude that the USLE is sufficiently sensitive to detect differences in soil
loss between the two land uses. There is, however, a need to improve the
operation of the model in some respects. The use of farm dams for
estimating sediment yield also shows promise.
38
Mokoena, Karabo. „Decentralisation of water resource management : a comparative review of catchment management authorities in South Africa and Victoria, Australia“. Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/19783.
Annotation:
By the adoption of Integrated Water Resource Management (IWRM), South Africa has significantly changed its water management regime and the institutions governing water in this country. These changes were first introduced by the National White Policy Paper on Water in South Africa in 1997 and subsequently the National Water Act in 1998. One of the key components of IWRM is the decentralisation of water management to a regional or catchment level and the introduction of public participation in the water management sector. With the enactment of the NWA South Africa incorporated IWRM in its legal system and a decade on, authorities are now turning to its implementation. The NWA introduces Catchment Management Agencies (CMAs) in water management and gives them authority over water management at a catchment level. Initially there were nineteen (19) and this number has since been reduced to nine (9) due to a number of factors. South African authorities are now seeking ways in which they can effectively decentralise water to a catchment level, including delegating and assigning some of the functions currently held by the Minster to CMAs. Using Victoria, Australia as a comparative study, this study investigates how water management can best be decentralised to a catchment level; it starts off by investigating the theory of decentralisation and its pros and cons; then sets off to investigate water management has been decentralised in Australia from the national level, to state level and catchment level; it then investigates the role of Rural Water Authorities in Victoria and compares them to Catchment Management Agencies in South Africa. Finally the work highlights the water management regime and the various stakeholders in water management South Africa from a national level to a catchment level and the challenges facing South Africa in term of WRM; and then makes recommendations and a conclusion based on its research findings and the South African socio-economic and political context.
39
Situmorang, Rahel. „The concept of ecological sustainability and coastal development, with reference to South Australia /“. Title page, contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09PL/09plms623.pdf.
40
Mugford, John S. „Towards an equitable land-use policy in the Mount Bold catchment of South Australia /“. Title page, contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09ENV/09envm951.pdf.
41
Ritson, Peter. „Growth, yield and carbon sequestration of pinus pinaster established on farmland in south-western Australia /“. Connect to thesis, 2004. http://eprints.unimelb.edu.au/archive/00001319.
Annotation:
Thesis (Ph.D.)--University of Melbourne, School of Forest and Ecosystem Science,Institute of Land and Food Resources, 2005.Typescript (photocopy). Includes bibliographical references (leaves 253-263).
42
Warren, Samantha. „A geostatistical study of soil profile data from an irrigated vineyard in the Hundred of Markaranka, Riverland, South Australia /“. Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09SB/09sbw293.pdf.
43
Shrestha, Hari Ram. „Post-fire recovery of carbon and nitrogen in sub-alpine soils of South-eastern Australia /“. Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/6963.
Annotation:
The forests of south-eastern Australia, having evolved in one of the most fire-prone environments in the world, are characterized by many adaptations to recovery following burning. Thus forest ecosystems are characterized by rapid regenerative capacity, from either seed or re-sprouting, and mechanisms to recover nutrients volatilized, including an abundance of N2 fixing plants in natural assemblages. Soil physical, chemical and biological properties are directly altered during fire due to heating and oxidation of soil organic matter, and after fire due to changes in heat, light and moisture inputs. In natural ecosystems, carbon (C) and nitrogen (N) lost from soil due to fires are recovered through photosynthesis and biological N2 fixation (BNF) by regenerating vegetation and soil microbes.This study investigated post-fire recovery of soil C and N in four structurally different sub-alpine plant communities (grassland, heathland, Snowgum and Alpine ash) of south-eastern Australia which were extensively burnt by landscape-scale fires in 2003. The amount and isotopic concentration of C and N in soils to a depth of 20 cm from Alpine ash forest were assessed five years after fire in 2008 and results were integrated with measurements taken immediately prior to burning (2002) and annually afterwards.
Because the historical data set, comprised of three soil samplings over the years 2002 to 2005, consisted of soil total C and N values which were determined as an adjunct to 13C and 15N isotopic studies, it was necessary to establish the accuracy of these IRMS-derived measurements prior to further analysis of the dataset. Two well-established and robust methods for determining soil C (total C by LECO and oxidizable C by the Walkley-Black method) were compared with the IRMS total C measurement in a one-off sampling to establish equivalence prior to assembling a time-course change in soil C from immediately pre-fire to five years post-fire. The LECO and IRMS dry combustion measurements were essentially the same (r2 >0.99), while soil oxidizable C recovery by the Walkley-Black method (wet digestion) was 68% compared to the LECO/IRMS measurements of total C. Thus the total C measurement derived from the much smaller sample size (approximately 15 mg) combusted during IRMS are equivalent to LECO measurement which require about 150 mg of sample.
Both total C and N in the soil of Alpine ash forests were significantly higher than soils from Snowgum, heathland and grassland communities. The ratio of soil NH4+ to NO3- concentration was greater for Alpine ash forest and Snow gum woodland but both N-fractions were similar for heathland and grassland soils. The abundance of soil 15N and 13C was significantly depleted in Alpine ash but both isotopes were enriched in the heathland compared to the other ecosystems. Abundance of both 15N and 13C increased with soil depth.
The natural abundance of 15N and 13C in the foliage of a subset of non-N2 fixing and N2 fixing plants was measured as a guide to estimate BNF inputs. Foliage N concentration was significantly greater in N2 fixers than non-N2 fixers while C content and 13C abundance were similar in both functional groups. Abundance of 15N was depleted in the N2 fixing species but was not significantly different from the non-N2 fixers to confidently calculate BNF inputs based on the 15N abundance in the leaves.
The total C pool in soil (to 20 cm depth) had not yet returned to the pre-fire levels in 2008 and it was estimated that such levels of C would be reached in another 6-7 years (about 12 years after the fire). The C and N of soil organic matter were significantly enriched in 15N and 13C isotopes after fire and had not returned to the pre-fire levels five years after the fire. It is concluded that the soil organic N pool can recover faster than the total C pool after the fire in the Alpine ash forests.
44
Alexander, Kathy. „Promoting health at the local level : a management and planning model for primary health care services /“. Title page, contents and introduction only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09pha376.pdf.
45
Kremor, Andrew George. „Engineering geological factors affecting slope stability in soft brown coal deposits : a South Australian example /“. Title page, contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09PH/09phk898.pdf.
46
Tynan, R. W. „Stocking limits for South Australian pastoral leases : historical background and relationship with modern ecological and management theory“. Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09AS/09ast987.pdf.
47
Goudie, Sharyn Leanne, und sharyngoudie@yahoo com au. „The Prospect of Independence: A critique and proposal for responding to youth homelessness in South Australia“. Flinders University. Flinders Institute of Public Policy and Management, 2009. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20090630.143621.
Annotation:
The lack of resources a young person brings with them to their experience of being homeless dramatically impacts on their ability to get out of homelessness. Young people who become homeless come with limited experience of successful independent living and at a life stage in which they are still developing physically, intellectually and psychologically. Johnson (2006) found that the younger a person was when they first became homeless the more likely they would remain homeless for a longer period of time. Evidence also shows that the longer someone remains homeless the more likely it is that they will develop substance use and/or mental health issues, further reducing their opportunities to get out of homelessness.
Youth homelessness disrupts schooling and limits future opportunities for economic participation, placing these young people well and truly at the bottom of the labour market. This paper asks Given that young people follow a unique pathway to homelessness, what supports and services are needed to effectively respond to this
group?
This paper is divided into three sections a critique of the characteristics of young
people who become homeless, a review of current theories of intervention and government responses, and finally a proposal for an improved response to young people who are at risk of becoming or who are already homeless.
48
Caton, Brian. „The conservation of scenic coasts : an examination of the English heritage system and its possible use in South Australia /“. Title page, contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09ENV/09envc366.pdf.
49
Morrison, Judith Ellen. „Independent scholarly reporting about conflict interventions : negotiating Aboriginal Native Title in South Australia /“. Morrison, Judith Ellen (2007) Independent scholarly reporting about conflict interventions: negotiating aboriginal native title in south Australia. PhD thesis, Murdoch University, 2007. http://researchrepository.murdoch.edu.au/210/.
Annotation:
This thesis uses an action research methodology to develop a framework for improving independent scholarly reporting about interventions addressing social or environmental conflict. As there are often contradictory interpretations about the causes and strategic responses to conflict, the problem confronting scholar-reporters is how to address perceptions of bias and reflexively specify the purpose of reporting. It is proposed that scholar-reporters require grounding in conventional realist-based social theory but equally ability to incorporate theoretical ideas generated in more idealist-based peace research and applied conflict resolution studies. To do this scholar-reporters can take a comparative approach systematically developed through an integrated framework as described in this thesis.
Conceptual and theoretical considerations that support both conventional and more radical constructions are comparatively analysed and then tested in relation to a case study. In 2000 Aboriginal people throughout South Australia deliberated whether their native title claims could be better accorded recognition through conservative court processes or a negotiation process to allay deep-seated conflict. The author, in a scholar-reporter capacity, formulated a report attributing meaning to this consultative process.
As such a report could have been formulated according to alternative paradigms, methodological approaches and theoretical frameworks, the analysis of the adopted framework highlights how different approaches can bias the interpretation of the process and prospects for change. Realist-based conservative interpretations emphasise 'official' decision-making processes where legitimacy is expressed through political and legal frameworks based on precedent. Idealist-based interpretations emphasise that circumstances entailing significant conflict warrant equal consideration being given to 'non-official' 'resolutionary' problem-solving processes where conflict is treated as a catalyst for learning and outcomes are articulated as understanding generated about conflict and how different strategies can transform it.
The developed integrated framework approach establishes the independence of scholarly reporting. Its purpose goes beyond perpetuating scholarly debate about alternative 'objective' understandings of conflict; it focuses primarily on communicating a more inclusive understanding of the contradictions inherent in a particular conflict. It increases the capacity to understand when, where, why and how conflict precipitates social change, and articulates possibilities for reconceptualising what might be the more sustainable direction of change.
50
McElhinny, Chris. „Quantifying stand structural complexity in woodland and dry sclerophyll forest, South-Eastern Australia /“. View thesis entry in Australian Digital Theses Program, 2005. http://thesis.anu.edu.au/public/adt-ANU20060322.133914/index.html.