Gotowe bibliografie tematyczne / Soil mechanics South Australia

Gotowa bibliografia na temat „Soil mechanics South Australia”

Autor: Grafiati

Data publikacji: 4 czerwca 2021

Data aktualizacji: 28 stycznia 2023

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Artykuły w czasopismach na temat "Soil mechanics South Australia"

Baker, G. H., P. J. Carter i V. J. Barrett. "Survival and biomass of exotic earthworms, Aporrectodea spp. (Lumbricidae), when introduced to pastures in south-eastern Australia". Australian Journal of Agricultural Research 50, nr 7 (1999): 1233. http://dx.doi.org/10.1071/ar98181.

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The earthworm fauna of pastures in south-eastern Australia is dominated by exotic lumbricid earthworms, in particular the endogeic species, Aporrectodea caliginosa and A. trapezoides. Anecic species such as A. longa are very rare. All 3 species were introduced within cages in 10 pastures on a range of soil types within the region. Five months later, A. longa had generally survived the best and A. trapezoides the worst. The survivals and weights of individual worms varied between sites for all 3 species. The survivals of A. caliginosa and A. longa, and to a lesser extent A. trapezoides, were positively correlated with soil clay content. The weights of A. caliginosa and A. longa, but not A. trapezoides, were positively correlated with soil P content. The survivals and weights of A. longa and A. trapezoides and the weights only of A. caliginosa decreased with increasing inoculation density, suggesting increased intraspecific competition for resources, particularly in the first two species. A. longa reduced the abundance and biomass of the exotic acanthodrilid earthworm, Microscolex dubius, at one site, and the total biomass of 3 native megascolecid species at another, when these latter species occurred as contaminants in A. longa cages. The addition of lime had no effect on the survivals and weights of A. caliginosa, A. longa, and A. trapezoides, although the soils were acid at the sites tested. The addition of sheep dung increased the survival and weights of some species at some sites. Mechanical disturbance of the soil within cages reduced the survivals of A. longa and A. trapezoides. A. longa was released without being caged at 25 sites within one pasture in South Australia. Four years later, it was recovered at all release points. A. longa has the potential to colonise pastures widely throughout the higher rainfall regions of south-eastern Australia.

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Luck, Joanne E., Rosa Crnov, Barbara Czerniakowski, Ian W. Smith i Jane R. Moran. "Investigating the Presence of Biotic Agents Associated with Mundulla Yellows". Plant Disease 90, nr 4 (kwiecień 2006): 404–10. http://dx.doi.org/10.1094/pd-90-0404.

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The role of biotic agents in the dieback syndrome Mundulla Yellows (MY) was investigated by analysis of 40 Eucalyptus camaldulensis, E. leucoxylon, or E. cladocalyx trees and soil samples from South Australia and Victoria, Australia. No pathogenic fungi, bacteria, phytoplasmas, or insect pests or vectors were found to be associated with MY. However, nematode analysis identified Merlinius spp. to be associated with soil, but not roots, from symptomatic trees. Interveinal chlorosis symptoms were not transmissible by seed, mechanical inoculation, or grafting using plant material derived from symptomatic trees. Virus-like particles were detected at a single symptomatic study site using transmission electron microscopy. MY symptoms were induced in E. camaldulensis seedlings by sowing seed from asymptomatic trees into sterilized and unsterilized soil collected from underneath symptomatic trees. Significantly, sterilized soil induced more severe symptoms in seedlings than unsterilized soil. Soil collected from under asymptomatic trees did not induce MY symptoms. This preliminary investigation indicates that, with the exception of Merlinius spp., pathogenic organisms and pests were not consistently associated with MY symptoms.

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Pickering, Bianca J., Jamie E. Burton, Trent D. Penman, Madeleine A. Grant i Jane G. Cawson. "Long-Term Response of Fuel to Mechanical Mastication in South-Eastern Australia". Fire 5, nr 3 (3.06.2022): 76. http://dx.doi.org/10.3390/fire5030076.

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Mechanical mastication is a fuel management strategy that modifies vegetation structure to reduce the impact of wildfire. Although past research has quantified immediate changes to fuel post-mastication, few studies consider longer-term fuel trajectories and climatic drivers of this change. Our study sought to quantify changes to fuel loads and structure over time following mastication and as a function of landscape aridity. Measurements were made at 63 sites in Victoria, Australia. All sites had been masticated within the previous 9 years to remove over-abundant shrubs and small trees. We used generalised additive models to explore trends over time and along an aridity gradient. Surface fuel loads were highest immediately post-mastication and in the most arid sites. The surface fine fuel load declined over time, whereas the surface coarse fuel load remained high; these trends occurred irrespective of landscape aridity. Standing fuel (understorey and midstorey vegetation) regenerated consistently, but shrub cover was still substantially low at 9 years post-mastication. Fire managers need to consider the trade-off between a persistently higher surface coarse fuel load and reduced shrub cover to evaluate the efficacy of mastication for fuel management. Coarse fuel may increase soil heating and smoke emissions, but less shrub cover will likely moderate fire behaviour.

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Crombie, DS, JT Tippett i TC Hill. "Dawn Water Potential and Root Depth of Trees and Understorey Species in Southwestern Australia". Australian Journal of Botany 36, nr 6 (1988): 621. http://dx.doi.org/10.1071/bt9880621.

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Water relations of selected tree and understorey species in the jarrah forest of south-western Australia were studied during summer drought and the results related to root morphology. Seasonal patterns of predawn water potential (Ψp) differed between species according to root depth and between sites according to average annual rainfall. Dawn water potentials fell most rapidly and by the greatest amount in plants with the shallowest roots. Dawn water potentials of medium and deep rooted species were not consistently different. Separation of Ψp between sites of different annual rainfall was less marked than was separation by root depth. Changes in Ψp, were consistent with a top-to-bottom drying of the soil profiles. We suggest that measurements of Ψp of plants of appropriate root depth can be used to monitor the drying of soils as an alternative to more expensive mechanical and electrical methods.

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Abdallah, Ahmed M., Hanuman S. Jat, Madhu Choudhary, Emad F. Abdelaty, Parbodh C. Sharma i Mangi L. Jat. "Conservation Agriculture Effects on Soil Water Holding Capacity and Water-Saving Varied with Management Practices and Agroecological Conditions: A Review". Agronomy 11, nr 9 (24.08.2021): 1681. http://dx.doi.org/10.3390/agronomy11091681.

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Improving soil water holding capacity (WHC) through conservation agriculture (CA)-practices, i.e., minimum mechanical soil disturbance, crop diversification, and soil mulch cover/crop residue retention, could buffer soil resilience against climate change. CA-practices could increase soil organic carbon (SOC) and alter pore size distribution (PSD); thus, they could improve soil WHC. This paper aims to review to what extent CA-practices can influence soil WHC and water-availability through SOC build-up and the change of the PSD. In general, the sequestered SOC due to the adoption of CA does not translate into a significant increase in soil WHC, because the increase in SOC is limited to the top 5–10 cm, which limits the capacity of SOC to increase the WHC of the whole soil profile. The effect of CA-practices on PSD had a slight effect on soil WHC, because long-term adoption of CA-practices increases macro- and bio-porosity at the expense of the water-holding pores. However, a positive effect of CA-practices on water-saving and availability has been widely reported. Researchers attributed this positive effect to the increase in water infiltration and reduction in evaporation from the soil surface (due to mulching crop residue). In conclusion, the benefits of CA in the SOC and soil WHC requires considering the whole soil profile, not only the top soil layer. The positive effect of CA on water-saving is attributed to increasing water infiltration and reducing evaporation from the soil surface. CA-practices’ effects are more evident in arid and semi-arid regions; therefore, arable-lands in Sub-Sahara Africa, Australia, and South-Asia are expected to benefit more. This review enhances our understanding of the role of SOC and its quantitative effect in increasing water availability and soil resilience to climate change.

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Jettner, R., S. P. Loss, L. D. Martin i K. H. M. Siddique. "Responses of faba bean (Vicia faba L.) to sowing rate in south-western Australia II Canopy development, radiation absorption and dry matter partitioning". Australian Journal of Agricultural Research 49, nr 6 (1998): 999. http://dx.doi.org/10.1071/a98003.

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Sowing rate influences plant density, canopy development, radiation absorption, dry matter production and its partitioning, and seed yield. The canopy development, radiation interception, and dry matter partitioning of faba bean (cv. Fiord) were examined using 6 sowing rate treatments from 70 to 270 kg/ha in field experiments conducted over 3 years at Northam as part of a larger investigation of sowing rate responses in faba bean in south-western Australia. High sowing rates resulted in significantly earlier canopy closure, larger green area indexes, more radiation absorption, more dry matter accumulation particularly during the early vegetative stages, and greater seed yield than treatments where a low plant density was established. The results suggest that further increases in canopy development, radiation absorption, dry matter accumulation, and seed yield are possible by using sowing rates in excess of 270 kg/ha. The rate of node appearance was relatively constant within and across seasons (1 every 65·9 degree-days), whereas the number of branches per plant declined with increasing plant density, and less branches survived through to maturity at high density. The peak photosynthetically active radiation absorption (75-85%) measured at green area index of 2·9-3·8 in the highest sowing rate treatment in this study is similar to previous reports for other crops. The estimated radiation use efflciency (1·30 g/MJ) was constant across sowing rate treatments and seasons. High sowing rates produced tall crops with the lowest pods further from the soil surface than those at low plant density, and hence, mechanical harvesting was easier. The growth of individual plants may have been limited by the low growing season rainfall (266-441 mm) and/or low soil pH (5·0 in CaCl2) at the site, and competition between plants for radiation was probably small even at the highest sowing rate. Early canopy closure and greater dry matter production with high sowing rates may also cause greater suppression of weeds and aphids.

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Regan, K. L., K. H. M. Siddique i L. D. Martin. "Response of kabuli chickpea (Cicer arietinum L.) to sowing rate in Mediterranean-type environments of south-western Australia". Australian Journal of Experimental Agriculture 43, nr 1 (2003): 87. http://dx.doi.org/10.1071/ea01200.

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The effect of sowing rate (60–320 kg/ha) on the growth and seed yield of kabuli chickpea (cv. Kaniva) was assessed at 11 sites for 4 seasons in the cropping regions of south-western Australia. The economic optimum plant density and yield potential were estimated using an asymptotic model fitted to the data and calculating the sowing rate above which the cost of additional seed was equivalent to the revenue that could be achieved from the extra seed yield produced, assuming a 10 and 50% opportunity cost. On average for all sites and seasons, plant densities ranged from 10 plants/m2 when sown at 60 kg/ha to 43�plants/m2 when sown at 320 kg/ha. Assuming a mean seed weight of 400 mg and a germination of 80%, then on average 75% of viable seeds sown (or 60% of sown seeds) established as plants. The poor establishment rates are thought to be associated with reduced viability caused by mechanical damage, storage conditions, fungal infection in the soil, and unfavourable seed bed moisture and temperatures. In general, there was a positive relationship between sowing rate and seed yield. Seed yield increases at higher sowing rates were mainly associated with the greater number of plants per unit area. There were fewer pods per plant at higher sowing rates, but there were more pods per unit area. Changing the sowing rate had little effect on mean seed weight and the number of seeds per pod. The economic optimum plant density varied from 8 to 68 plants/m2, depending on the location, but the mean (27�plants/m2) was within the range currently recommended in southern Australia (25–35 plants/m2). Due to the low establishment rates observed in this study, we estimate a sowing rate greater (160–185 kg/ha) than currently suggested (110–160 kg/ha) to achieve this density. There was a strong relationship between economic optimum plant density and seed yield potential (r2 = 0.66, P<0.01), which allows an estimation of the most profitable sowing rate, depending on the seed yield potential of the site. For most crops yielding about 1.0 t/ha in southern Australia, a plant density of 25 plants/m2 is most profitable, while in higher-yielding situations (>1.5 t/ha) plant densities >35�plants/m2 will produce the most profit.

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SINGH, B., i R. J. GILKES. "Properties of soil kaolinites from south-western Australia". Journal of Soil Science 43, nr 4 (grudzień 1992): 645–67. http://dx.doi.org/10.1111/j.1365-2389.1992.tb00165.x.

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Aldaoud, R., W. Guppy, L. Callinan, S. F. Flett, K. A. Wratten, G. A. Murray, T. Cook i A. McAllister. "Occurrence of Phytophthora clandestina in Trifolium subterraneum paddocks in Australia". Australian Journal of Experimental Agriculture 41, nr 2 (2001): 187. http://dx.doi.org/10.1071/ea00048.

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In 1995–96, a survey of soil samples from subterranean clover (Trifolium subterraneum L.) paddocks was conducted across Victoria, South Australia, New South Wales and Western Australia, to determine the distribution and the prevalence of races of Phytophthora clandestina (as determined by the development of root rot on differential cultivars), and the association of its occurrence with paddock variables. In all states, there was a weak but significant association between P. clandestina detected in soil samples and subsequent root rot susceptibility of differential cultivars grown in these soil samples. Phytophthora clandestina was found in 38% of the sampled sites, with a significantly lower prevalence in South Australia (27%). There were significant positive associations between P. clandestina detection and increased soil salinity (Western Australia), early growth stages of subterranean clover (Victoria), mature subterranean clover (South Australia), recently sown subterranean clover (South Australia), paddocks with higher subterranean clover content (Victoria), where herbicides were not applied (South Australia), irrigation (New South Wales and Victoria), cattle grazing (South Australia and Victoria), early sampling dates (Victoria and New South Wales), sampling shortly after the autumn break or first irrigation (Victoria), shorter soil storage time (Victoria) and farmer’s perception of root rot being present (Victoria and New South Wales). Only 29% of P. clandestina isolates could be classified under the 5 known races. Some of the unknown races were virulent on cv. Seaton Park LF (most resistant) and others were avirulent on cv. Woogenellup (most susceptible). Race 1 was significantly less prevalent in South Australia than Victoria and race 0 was significantly less prevalent in New South Wales than in South Australia and Western Australia. This study revealed extremely wide variation in the virulence of P. clandestina. The potential importance of the results on programs to breed for resistance to root rot are discussed. in South Australia.

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St. Pierre, Tim G. "Mössbauer Spectra of Soil Kaolins from South-Western Australia". Clays and Clay Minerals 40, nr 3 (1992): 341–46. http://dx.doi.org/10.1346/ccmn.1992.0400315.

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Rozprawy doktorskie na temat "Soil mechanics South Australia"

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.

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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.

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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.

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Esfandiari, Baiat Mansour, of Western Sydney Hawkesbury University, of Science Technology and Agriculture Faculty i 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.

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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)

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Huang, Chunyuan. "Mechanisms of Mn efficiency in barley". 1996, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phh8739.pdf.

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Bibliography: leaves 131-153. This thesis investigates the mechanisms of manganese (Mn) efficiency (genetic tolerance to Mn-deficient soils) in barley (Hordeum vulgare L.) at both physiological and molecular levels.

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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.

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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).

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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.

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Pritchard, Deborah Leeanne. "Phosphorus bioavailability from land-applied biosolids in south-western Australia". Thesis, Curtin University, 2005. http://hdl.handle.net/20.500.11937/2380.

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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.

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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.

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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.

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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.

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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.

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Książki na temat "Soil mechanics South Australia"

Australia-New Zealand Conference on Geomechanics (8th 1999 Hobart, Tas.). 8th Australia New Zealand Conference on Geomechanics, Hobart: Proceedings. Barton, ACT: Australian Geomechanics Society, 1999.

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Regional, Conference for Africa on Soil Mechanics and Geotechnical Engineering 12th Durban 1999. Geotechnics for developing Africa = La géotechnique au service du développement de l'Afrique: Proceedings of the Twelfth Regional Conference for Africa on Soil Mechanics and Geotechnical Engineering, Durban, South Africa, 25-27 October 1999 = comptes rendus [...]. Rotterdam: Balkema, 1999.

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Cruden, D. M. Monitoring the south peak of Turtle Mountain, 1980 to 1985. Edmonton: The Division, 1986.

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Silverton), South African Geotechnical Conference (1980. South African Geotechnical Conference, 1980: Proceedings of the South African Geotechnical Conference organised by the Geotechnical Engineering Division of the South African Institution of Civil Engineers, Silverton, 11-13 November 1980. Rotterdam: Balkema, 1985.

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Runge, Werner. Land qualities in the south-west of Western Australia: A summary of land degradation and land capability. Nedlands, W.A: Dept. of Geography, University of Western Australia, 1999.

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Booker, Memorial Symposium (2000 Sydney N. S. W. ). Developments in theoretical geomechanics: Proceedings of the Booker Memorial Symposium, Sydney, N.S.W., Australia, 16-17 November 2000. Rotterdam: A.A. Balkema, 2000.

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Hurlow, Hugh A. Geology and ground-water chemistry, Curlew Valley, Northwestern Utah and South-Central Idaho, implications for hydrogeology. Salt Lake City, Utah: Utah Geological Survey, 2008.

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Conference on Probabilistic Methods in Geotechnical Engineering (1993 Canberra, A.C.T.). Probabilistic methods in geotechnical engineering: Proceedings of the Conference on Probabilistic Methods in Geotechnical Engineering, Canberra, Australia, 10-12 February 1993. Rotterdam: A.A. Balkema, 1993.

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Abdelmalek, Bouazza, Kodikara Jayantha i Parker Roger, red. Environmental geotechnics: Proceedings of the 1st Australia-New Zealand Conference on Environmental Geotechnics-Geoenvironment 97 : Melbourne/Victoria/Australia, 26-28 November, 1997. Rotterdam: A.A. Balkema, 1997.

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Australasian Conference on the Mechanics of Structures and Materials (16th 1999 Sydney, N.S.W.). Mechanics of structures and materials: Proceedings of the 16th Australasian Conference on the Mechanics of Structures and Materials, Sydney, New South Wales, Australia, 8-10 December 1999. Rotterdam: A.A. Balkema, 1999.

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Części książek na temat "Soil mechanics South Australia"

Gratchev, Ivan, Sinnappoo Ravindran, Dong Hyun Kim, Chen Cui i Qianhao Tang. "Mechanisms of Shallow Rainfall-Induced Landslides from Australia: Insights into Field and Laboratory Investigations". W Progress in Landslide Research and Technology, Volume 1 Issue 1, 2022, 113–22. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-16898-7_7.

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AbstractThis paper presents and discusses the mechanisms of rainfall-induced shallow landslides that commonly occur in South East Queensland (SEQ) and northern New South Wales (NSW), Australia. The major factors causing the formation of landslide mass such as geology, weathering, and rainfall patterns were discussed. Results from field surveys and laboratory testing of rock/soil material from landslide masses were presented, and relationships between the material strength and landslide occurrence were drawn. It was found that most of shallow slides were related to sandstone deposits. Those failures occurred on natural slopes and road cuts with the inclination of the failure plane being in the range of 35–45°. For natural slopes where the landslide mass mostly consisted of coarse-grained soil, the relationship between the soil strength and water content was established. In addition, the relationship between rainfall patterns such as intensity and duration, and the landslide occurrence was presented. Based on the data from field work and laboratory results including a series of flume tests, the mechanism of shallow landslides triggered by rainfall events was identified and discussed.

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Berveling, Steven. "Decontamination Responsibilities of Local Authorities in New South Wales, Australia". W Soil & Environment, 119–20. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-2018-0_15.

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Merry, R. H., T. J. V. Hodge, D. C. Lewis i J. Jacka. "Evaluation of liming materials used in South Australia". W Plant-Soil Interactions at Low pH: Principles and Management, 497–503. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0221-6_76.

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McBratney, Alex B., i John Triantafilis. "Fuzzy Soil Layer, Profile and Suitability Classification in the Lower Manoi Valley, New South Wales, Australia". W Soil & Environment, 515–17. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-2008-1_113.

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Leys, J. F. "The threshold friction velocities and soil flux rates of selected soils in south-west New South Wales, Australia". W Aeolian Grain Transport, 103–12. Vienna: Springer Vienna, 1991. http://dx.doi.org/10.1007/978-3-7091-6703-8_8.

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Oliver, D. P., K. G. Tiller, M. K. Conyers, W. J. Slattery, R. H. Merry i A. M. Alston. "The effects of soil pH on Cd concentration in wheat grain grown in south-eastern Australia". W Plant-Soil Interactions at Low pH: Principles and Management, 791–95. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0221-6_127.

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Slattery, J. F., W. J. Slattery i B. M. Carmody. "Influence of Soil Chemical Characteristics on Medic Rhizobia in the Alkaline Soils of South Eastern Australia". W Highlights of Nitrogen Fixation Research, 243–49. Boston, MA: Springer US, 1999. http://dx.doi.org/10.1007/978-1-4615-4795-2_49.

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Baker, G. H., V. J. Barrett, P. J. Carter, J. C. Buckerfield, P. M. L. Williams i G. P. Kilpin. "Abundance of earthworms in soils used for cereal production in south-eastern Australia and their role in reducing soil acidity". W Plant-Soil Interactions at Low pH: Principles and Management, 213–18. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0221-6_30.

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Hollingsworth, I. D., R. Boardman i R. W. Fitzpatrick. "A Soil-Site Evaluation Index of Productivity in Intensively Managed Pinus Radiata (D. Don) Plantations in South Australia". W Global to Local: Ecological Land Classification, 531–41. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-1653-1_37.

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Sun, X., J. Li, A. Zhou i G. Ren. "The impacts of climate change on expansive soil movements in Australia". W Unsaturated Soil Mechanics - from Theory to Practice, 697–702. CRC Press, 2015. http://dx.doi.org/10.1201/b19248-116.

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Streszczenia konferencji na temat "Soil mechanics South Australia"

Fityus, Stephen, i J. Gibson. "Rock Mass Stability in the Southern New England Fold Belt, New South Wales, Australia". W First Southern Hemisphere International Rock Mechanics Symposium. Australian Centre for Geomechanics, Perth, 2008. http://dx.doi.org/10.36487/acg_repo/808_57.

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Shi, Xianzhong, Mehrooz Aspandiar i Ian C. Lau. "Assessment of acid sulfate soil using hyperspectral data in South Yunderup, Western Australia". W IGARSS 2013 - 2013 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2013. http://dx.doi.org/10.1109/igarss.2013.6723790.

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Sainsbury, David. "Analysis of River Bed Cracking Above Longwall Extraction Panels in the Southern Coalfield of New South Wales, Australia". W First Southern Hemisphere International Rock Mechanics Symposium. Australian Centre for Geomechanics, Perth, 2008. http://dx.doi.org/10.36487/acg_repo/808_137.

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"Evaluation of modelled and measured evaporation from a bare Vertosol soil in south east Queensland, Australia". W 20th International Congress on Modelling and Simulation (MODSIM2013). Modelling and Simulation Society of Australia and New Zealand (MSSANZ), Inc., 2013. http://dx.doi.org/10.36334/modsim.2013.j9.kodur.

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Rudiger, Christoph, Alessandra Monerris, David McJannet, Luigi Renzullo, Mariette Vreugdenhil i Wolfgang Wagner. "Comparison of Different High-Resolution Soil Moisture Products Across an Agricultural Landscape in South-Eastern Australia". W IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2018. http://dx.doi.org/10.1109/igarss.2018.8518208.

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Hewson, R. D., G. R. Taylor i L. B. Whitbourn. "Application of TIR Imagery and Spectroscopy for the Extraction of Soil Textural Information at Fowlers Gap, Western New South Wales, Australia". W IGARSS 2008 - 2008 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2008. http://dx.doi.org/10.1109/igarss.2008.4779095.

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Jing, Yuanshu, Buaphean Ruthaikarn, Xinyi Jin i Bo Pang. "The Artificial Neural Network Estimation for Daily and Hourly Rice Evapotranspiration in the Region of Red Soil, South China". W The 2015 International Conference on Applied Mechanics, Mechatronics and Intelligent Systems (AMMIS2015). WORLD SCIENTIFIC, 2015. http://dx.doi.org/10.1142/9789814733878_0094.

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Sigurdsson, Gudfinnur, Jan Mathisen, Pa˚l Stro̸m i Tok Kwong Goh. "Reliability Reassessment of a Jacket Platform With Gas Seepage in the South China Sea". W ASME 2003 22nd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2003. http://dx.doi.org/10.1115/omae2003-37472.

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A structural reliability analysis is carried out on a jacket platform in 75 m water depth, in the South China Sea. A platform collapse failure mode is considered, with emphasis on uncertain soil conditions around the pile foundations, due to gas seepage while the platform has been in service. Random environmental conditions due to wind, waves and current are taken into account, based on observed data. Allowance for the short duration of environmental measurements is included and has a marked effect on the results. Two response surfaces are applied in the reliability calculation, to model the loads and the system capacity.

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Gommenginger, C. P., M. A. Srokosz, P. G. Challenor i P. D. Cotton. "Measuring Ocean Wave Period and Wave Height With Satellite Altimeters". W ASME 2004 23rd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/omae2004-51423.

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A novel source of ocean wave period information based on satellite altimeters measurements is examined and compared — using monthly mean climatologies — with ECMWF ERA 40 output and NDBC buoy historical records. The altimeter derived wave period appears to perform well in regions dominated by wind seas, including the Southern Ocean, but does not depict the large swell events observed in the ERA 40 output West of South America and Australia. Altimeter wave period compares well in magnitude and variability with NDBC buoy historical records in three geographical regions (Alaska, Gulf of Mexico, Central Pacific), but further validation of the altimeter model is required against in situ data in regions dominated by swell.

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Hodder, M. S., D. J. White i M. J. Cassidy. "Centrifuge Modelling of Riser-Soil Stiffness Degradation in the Touchdown Zone of a Steel Catenary Riser". W ASME 2008 27th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/omae2008-57302.

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Steel catenary risers (SCRs) are economical to assemble and install compared to conventional vertical risers. However, accurate evaluation of the fatigue life of an SCR remains a major challenge due to uncertainty surrounding the interaction forces at the seabed within the touchdown zone (TDZ). Fatigue life predictions are heavily dependant on the assumed stiffness between the riser and the seabed and therefore an accurate assessment of seabed stiffness — or more specifically the nonlinear pipe-soil resistance — is required. During the lifespan of an SCR, vessel motions due to environmental loading cause repeated penetration of the riser into the seabed within the TDZ. This behaviour makes assessment of seabed stiffness difficult due to the gross deformations of the seabed and the resulting soil remoulding and water entrainment. This paper describes a model test in which the movement of a length of riser pipe was simulated within the geotechnical beam centrifuge at the University of Western Australia. The model soil was soft, lightly over-consolidated kaolin clay with a linearly increasing shear strength profile with depth, typical of deepwater conditions. The pipe was cycled over a fixed vertical distance from an invert embedment of 0.5 diameters to above the soil surface. This range represents a typical vertical oscillation range of a section of riser within the TDZ during storm loading. The results indicate a significant degradation in the vertical pipe-soil resistance during cyclic vertical movements. Due to the cyclic degradation in soil strength, the component of the vertical resistance created by buoyancy was significant, particularly due to the influence of heave. A new approach to the interpretation of heave-enhanced buoyancy was used to extract the separate influences of soil strength and buoyancy, allowing the cyclic degradation in strength to be quantified. During cycling, the soil strength reduced by a factor of 7.5 relative to the initial penetration stage. This degradation was more significant than the reduction in soil strength during a cyclic T-bar penetration test. This contrast can be attributed to the breakaway of the pipe from the soil surface which allowed water entrainment. This dramatic loss of strength and therefore secant stiffness, and the significance of the buoyancy term in the total vertical pipe-soil resistance, has implications for the fatigue assessment of SCRs.

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