460 resultados para South Australia


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The Glenelg spiny freshwater crayfish Euastacus bispinosus is a large endangered freshwater invertebrate of southeastern Australia that has suffered major population declines over the last century. Disjunct populations in the state of South Australia are in a particularly critical condition, restricted to a few isolated rising-spring habitats and in an ongoing state of decline. We assessed genetic diversity and gene flow within E. bispinosus across its current range using allele frequencies from 11 nuclear microsatellite loci and DNA sequence data from a single mitochon -drial locus (cytochrome oxidase subunit I). Populations were characterized by low levels of genetic diversity and found to be highly structured, with gene flow restricted both within and across catchments, highlighting the species' vulnerability to further habitat fragmentation and the importance of managing environmental threats on local scales across its current natural range. South Australian populations were characterized by critically low levels of genetic diversity generally, highlighting their potential vulnerability to localized extinction. Holistic conservation efforts are necessary to conserve populations, including local habitat management and, potentially, translocations to increase genetic diversity and evolutionary potential, and reduce possible inbreeding effects and the threat of extinction.

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The Glenelg spiny crayfish, Euastacus bispinosus, is an iconic freshwater invertebrate of south eastern Australia and listed as 'endangered' under the Environment Protection and Biodiversity Conservation Act 1999, and 'vulnerable' under the International Union for Conservation of Nature's Red List. The species has suffered major population declines as a result of over-fishing, low environmental flows, the introduction of invasive fish species and habitat degradation. In order to develop an effective conservation strategy, patterns of gene flow, genetic structure and genetic diversity across the species distribution need to be clearly understood. In this study we develop a suite of polymorphic microsatellite markers by next generation sequencing. A total of 15 polymorphic loci were identified and 10 characterized using 22 individuals from the lower Glenelg River. We observed low to moderate genetic variation across most loci (mean number of alleles per locus = 2.80; mean expected heterozygosity = 0.36) with no evidence of individual loci deviating significantly from Hardy-Weinberg equilibrium. Marker independence was confirmed with tests for linkage disequilibrium, and analyses indicated no evidence of null alleles across loci. Individuals from two additional sites (Crawford River, Victoria; Ewens Ponds Conservation Park, South Australia) were genotyped at all 10 loci and a preliminary investigation of genetic diversity and population structure was undertaken. Analyses indicate high levels of genetic differentiation among sample locations (F ST = 0.49), while the Ewens Ponds population is genetically homogeneous, indicating a likely small founder group and ongoing inbreeding. Management actions will be needed to restore genetic diversity in this and possibly other at risk populations. These markers will provide a valuable resource for future population genetic assessments so that an effective framework can be developed for implementing conservation strategies for E. bispinosus.

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Aim. To evaluate the effectiveness of a public health intervention aimed at changing knowledge, attitudes and behaviour. Methods. A non-blinded parallel group randomised controlled trial of pregnant women over 18 years of age. Women were recruited in the second trimester and assigned to one of two treatment groups. Both groups completed an initial questionnaire assessing knowledge, attitudes, and practices relating to alcohol consumption during pregnancy. The intervention group then received a mocktail recipe booklet and participants were asked to share the information with their partner. The control group received standard antenatal care. A follow-up questionnaire was conducted four weeks post birth. Primary outcome measures were a knowledge score of the health risks associated with alcohol consumption during pregnancy and an attitude score toward drinking during pregnancy. Secondary outcome measures included whether or not the woman and her partner abstained from drinking. Ethical approval was granted by the Women’s and Children’s Health Network and the University of South Australia. Results. A total of 161 participants were recruited at baseline (intervention = 82, control = 79) and 96 participants completed the trial (intervention = 49, control = 47). The findings suggest that the mocktail booklet was effective at improving knowledge (p<0.001; effect size 0.80) and improving attitudes towards drinking during pregnancy (p=0.017; effect size 0.43) in the intervention group compared to the control group. Although women in the intervention group were 30% more likely to abstain from drinking than in the control group (RR=1.3, 95% CI 0.97 – 1.75), this result was not statistically significant (p=0.077). Conclusions. Knowledge regarding the effects of alcohol consumption as well as attitudes towards drinking significantly improved as a result of a mocktail recipe booklet. Improving knowledge and changing attitudes has the potential to change health behaviour. Therefore, this intervention may reduce the percentage of women who continue to drink alcohol while they are pregnant and improve outcomes for infants and children.

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The effect of isolation and the importance of dispersal in establishing and maintaining populations in fragments of remnant habitat remain poorly understood. Nevertheless, environmental connectivity is likely to be important for ensuring the long-term preservation of biodiversity in extensively cleared landscapes. In this study, we compared reptile communities in large conservation parks with those in small woodland remnants 6.5-12km from the parks, on the Eyre Peninsula, South Australia, Australia. We assessed the impact of fragmentation on the abundance, richness and habitat preferences of reptiles, and examined whether connection to linear roadside vegetation altered reptile communities in small woodland remnants. Of the 31 reptile species, 12 were restricted to conservation parks and six to habitat fragments in farmland. There was a substantial reduction in reptile species richness and abundance in farmland fragments. Direct connection of remnant vegetation to roadside corridors did not affect abundance of common species in the farmland fragments, although species richness was lower in isolated remnants in one of our two study regions. The habitat preference of the scincid lizard Menetia greyii differed between farmland fragments, where they were regularly found on dunes and roadsides, and conservation parks, where they were rare and not detected on dunes. We suggest that habitat fragmentation may have altered interspecific interactions, enabling an expansion of habitat use in the farming landscape. Significantly lower abundance of four common species in farmland settings compared with reserves indicated that existing corridors and small fragments provide inadequate connectivity over larger distances. To counter this effect, large reserves may need to be less than 10km apart.

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Compliance with legislation has been highlighted as a factor influencing the reluctance of small and medium sized enterprises to take on new employees. With the objective of determining factors influencing smaller firms in their employment decisions, mailed questionnaires were used to survey small to medium manufacturing businesses in the Australian States of Victoria and New South Wales. Significant critical factors and deterrents to further employment were identified.


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Physical characteristics of roost sites used by the lesser long-eared bat Nyctophilus geoffroyi and Gould's wattled bat Chalinolobus gouldii were investigated in a farmland–remnant vegetation mosaic and adjacent forested floodplain in south-eastern Australia. A total of 45 individuals of N. geoffroyi and 27 C. gouldii were fitted with radio-transmitters, resulting in the location of 139 and 89 roosts, respectively. Male N. geoffroyi roosted in trees, fallen and decayed timber and artificial structures. These roosts were low to the ground, mainly under bark and in cracks in timber. Roosts of female N. geoffroyi were located higher above ground, and all within trees. Maternity roosts were predominantly located in large dead trees, approximately twice the diameter of roost trees used by females outside the breeding season. No maternity roosts were found under bark, despite half the roosts used by non-breeding females being located in these situations. Both sexes roosted primarily in dead timber and used cavities where the narrowest dimension of the entrance was 2.5 cm. Most roosts of C. gouldii were in dead spouts on large, live river red gum Eucalyptus camaldulensis trees. Intraspecific differences in roost characteristics were less pronounced for this species. Despite access to the same roosting opportunities, there were marked differences in roost selection between N. geoffroyi and C. gouldii. Both species favoured large diameter trees, but differed significantly for all other measured variables: type of roost structure, condition of roost tree (live or dead), height of roost tree, height of roost, and entrance dimensions. Although these species are among the most widespread bats in Australia and are often considered to be habitat 'generalists', both displayed a high level of discrimination in the roosts used. Clearly, roosting requirements are a complex and important issue in the conservation of even the most common species of bats.

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From the First World War Australian port administration came under criticism from exporters, shipping companies and the Commonwealth government, all of whom argued that port authorities charges imposed an excessive burden on exporters. They sought the replacement of public port authorities by trusts representative of business interests. The campaign for port administration reform also diverted farmers from criticism of shipping freights and to secure their acquiescence in anti-competitive practices in the shipping industry. The formation of the Australian Overseas Transport Association in 1929 was the culmination of this campaign. Elite conservative political support for such anti-competitive practices reflected a belief that competitive capitalism was inherently unstable. The Scullin Labor of 1929-31 government abandoned Labor's earlier hostility to shipping companies to support cartelisation. Conservative state governments, in a more competitive electoral position than their federal counterparts and under greater financial pressure, deflected business calls for port administration reform. Business groups expected the NSW conservative government elected in 1932 to reform port administration towards a representative model, but the Maritime Services Board established in 1935 merely rationalised existing administrative structures. In the 1980s international economic instability legitimated the project of microeconomic reform, particularly in the maritime sector, but in the interwar period a different balance of capital, labour and the state meant that economic isolationism rather than integration was the policy outcome.

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The marron, Cherax tenuimanus (Smith), is one of the most easily recognisable members of the freshwater crayfish genus Cherax. Since its description in 1912, the taxonomy of the species has not been in dispute, but recent genetic studies have demonstrated that the species is not homogenous and consists of two genetically distinct forms. One of these forms is widespread and exploited via aquaculture and the other is restricted to a single river system, the Margaret River. This paper presents allozyme data, collected over a 19-year period, which documents the introduction of the widespread form into the Margaret River and the subsequent reproductive interactions between the two forms. These data indicate minimal interbreeding between the two forms of marron and so justify their recognition as distinct species. As the original description of the marron was based on specimens collected from the Margaret River, the form native to this river retains the name C. tenuimanus and a new species, Cherax cainii Austin is described for the common, widespread form of marron. An additional outcome of this study is that C. tenuimanus has been rapidly displaced by the introduced C. cainii within the Margaret River. Consequently, urgent conservation measures are required to protect C. tenuimanus and prevent its possible extinction.

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Meiofauna from Avicennia marina leaf litter in a temperate mangrove forest was enumerated, and the nematode assemblages compared on the bases of leaf colour (used as a guide to leaf age) and shore horizon where samples were collected. Twenty-one putative nematode species were collected from 48 leaf litter samples. Univariate analyses indicated that neither the colour of the leaf nor the shore horizon significantly affected abundance of nematodes. However, of the four (222) treatment groups, rarefaction curves revealed highest diversity on brown leaves from under the shade of the tree canopy (H'=0.751-0.126 SE, n=17). Species diversity of leaf litter nematodes was lower in this temperate mangrove system than reported from tropical mangrove studies. ANOSIM tests confirmed a significant effect of shore horizon on nematode assemblages. The dominant feeding group among nematodes was non-selective deposit feeders (7/21 species, but 77% of all nematodes). Epigrowth grazers were represented by 8/21 species of nematodes, but only 19% of the total number. Excised leaves became skeletonised by about 15 weeks. Shorter temporal scales of life cycles of nematodes compared with leaf degradation, and the dynamic nature of epibiontic assemblages, probably explain the similar assemblage structure on yellow and brown leaves.

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This paper examines the independent variables of perceived environmental uncertainty (PEU) and the cultural beliefs of collectivism/individualism between two countries, Australia and South Africa. These countries were chosen because Australia is a stable democracy and South Africa is an emerging democracy which is undergoing significant political, social and economic transformation. The purpose of this paper is to determine whether accountants' commitment to an organisation is associated with perceived environmental uncertainty, collectivism and nationality.

The results of this study suggest that individuals' organizational commitment is associated with nationality (South African and Australian) and that relationship is associated with their cultural beliefs (collectivism/individualism) and an environmental variable, perceived environmental uncertainty.

This research is regarded as important in that multi-national organisations operating in different political and social environments may choose to use different means to ensure the maximum organisational commitment from their employees, in particular, those who are professional accountants.

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The pathogen Phytophthora cinnamomi causes extensive 'dieback' of Australian native vegetation. This study investigated the distribution of infection in an area of significant sclerophyll vegetation in Australia. It aimed to determine the relationship of infection to site variables and to develop a predictive model of infection. Site variables recorded at 50 study sites included aspect, slope, altitude, proximity to road and road characteristics, soil profile characteristics and vegetation attributes. Soil and plant tissues were assayed for the presence of the pathogen. A geographical information systyem (GIS) was employed to provide accurate estimations of spatial variables and develop a predictive model for the distribution of P. cinnamomi. The pathogen was isolated from 76% of the study sites. Of the 17 site variables initially investigated during the study a logistic regression model identified only two, elevation and sun-index, as significant in determining the probability of infection. The presence of P. cinnamomi infection was negatively associated with elevation and positively associated with sun-index. The model predicted that up to 74% of the study area (11 875 ha) had a high probability of being affected by P. cinnamomi. However, the present areas of infection were small, providing an opportunity for management to minimize spread into highly susceptible uninvaded areas.

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This study was based on wild-caught blacklip abalone Haliotis rubra L., from Port Fairy waters, south eastern Australia (142°15′E; 38°21′S), from July  1998 to November 1999, and was initiated to evaluate the spawning season and other aspects of its reproductive biology. The shell length and body weight of female and male abalone sampled ranged from 12.0 to 18.6 and 12 to 15 cm, and 137 to 529 and 148 to 585 g, respectively. The sex ratio did not vary significantly from 1:1 through the year. The gonadosomatic index (GSI) ranged from 3.0% to 8.4% in males, and 2.5% to 14.1% for females, and the highest GSI as well as the highest proportion of mature animals were recorded from September to October. During these months the hepatosomatic index (HSI) was low, and an inverse correlation between GSI and HSI (P < 0.05) was evident. Fecundity of blacklip abalone ranged from 1.09 to 7.5 million eggs for females of 12–14.5 cm in length, and 115–487 g in total body weight, respectively. The lipid content of the female gonad increased significantly from about July to November, and an opposite trend was observed for lipid content of the digestive gland. Seasonal changes in the protein and ash contents of the gonad and/or the digestive gland were not always significant.

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In the budget review of23 February 2000, the South African Minister of Finance announced that a capital gains tax ('CGT') would be introduced into South Africa, the anticipated start date at that point being 1 April 2001. Pursuant to Taxation Laws Amendment Act 5 of 2001, a CGT of general operation was introduced into the South African Income Tax Act 58 of 1962 (the 'ITA 1962') through the insertion of the Eighth Schedule1, read together with s 26A of the Act. Section 26A is the charging provision that states that a person's taxable income included their 'taxable capital gain'. As discussed below, the start date was revised to 1 October 2001.