104 resultados para Shrimps - Geographical distribution - Australia


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Australian alpine ecosystems are expected to diminish in extent as global warming intensifies. Alpine vegetation patterns are influenced by the duration of snow cover including the presence of snowdrifts in summer, but there is little quantitative information on landscape-scale relationships between vegetation patterns and the frequency of occurrence of persistent summer snowdrifts in the Australian alps. We mapped annual changes in summer snowdrifts in the Kosciuszko alpine region, Australia, from Landsat TM images and modelled the frequency of occurrence of persistent summer snowdrifts from long-term records (1954–2003) of winter snow depth. We then compared vegetation composition and structure among four classes that differed in the frequency of occurrence of persistent summer snowdrifts. We found a curvilinear relationship between annual winter snow depth and the area occupied by persistent snowdrifts in the following summer (r2=0.9756). Only 21 ha (0.42% of study area) was predicted to have supported summer snowdrifts in 80% of the past 50 years, while 440 ha supported persistent summer snow in 10% of years. Mean cover and species richness of vascular plants declined significantly, and species composition varied significantly, as the frequency of summer snow persistence increased. Cushion plants and rushes were most abundant where summer snowdrifts occurred most frequently, and shrubs, grasses and sedges were most abundant in areas that did not support snowdrifts in summer. The results demonstrate strong regional relationships between vegetation composition and structure and the frequency of occurrence of persistent summer snowdrifts. Reductions in winter snow depth due to global warming are expected to lead to substantial reductions in the extent of persistent summer snowdrifts. As a consequence, shrubs, grasses and sedges are predicted to expand at the expense of cushion plants and rushes, reducing landscape vegetation diversity. Fortunately, few vascular plant species (e.g. Ranunculus niphophilus) appear to be totally restricted to areas where summer snow occurs most frequently. The results from this study highlight potential indicator species that could be monitored to assess the effects of global warming on Australian alpine environments.

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In Australia, numerous small mammal species have suffered extinction or severe declines in distribution and abundance following European settlement. The extent of these declines from forested areas of south-eastern Australia, however, remains poorly understood. In this paper we use sub-fossil deposits of the sooty owl (Tyto tenebricosa tenebricosa) as a tool for understanding the diversity of the small mammal palaeocommunity. These results are compared to the contemporary sooty owl diet from the same geographical region to investigate the degree of small mammal decline following European settlement. Of 28 mammal species detected in sub-fossil deposits and considered prey items of the sooty owl at the time of European settlement, only 10 species were detected in the contemporary sooty owl diet. Numerous small mammal species have not only recently suffered severe declines in distribution and abundance but have also recently undergone niche contraction, as they occupied a greater diversity of regions and habitats at the time of European settlement. For some species our understanding of their true ecological niche and ecological potential is therefore limited. The species that underwent the greatest declines occupied open habitat types or were terrestrial. The severity of decline is also likely to have resulted in severe disruption of ecosystem functions, with wide scale ecosystem consequences. There is an urgent need to improve small mammal conservation, to maintain crucial ecosystem functions performed by small mammals. It is recommended that broad-scale exotic predator control programs are conducted which may also provide suitable conditions for the re-introduction of locally extinct species.


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This article explores the changing contexts of international film exhibition in Australia over a 20-year period (1989–2009) by examining in some empirical detail Australia’s position in the global flow of films during this time. It argues that, at the most abstract level, distributors are engaged in the management and mediation of time and space in the field of global communications. It is proposed that distributors, through the organisation of temporal differentiation, are explicitly active in the creation of both cultural and commodity value. This is particularly apparent as film distributors explore and engage new methodologies of film release, which emphasise overlapping, intersecting and contradictory temporalities in the cinema experience.

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Determining the biological and environmental factors that limit the distribution and abundance of organisms is central to our understanding of the niche concept and crucial for predicting how species may respond to large-scale environmental change, such as global warming. However, detailed ecological information for the majority of species has been collected only at a local scale, and insufficient consideration has been given to geographical variation in intraspecific niche requirements. To evaluate the influence of environmental and biological factors on patterns of species distribution and abundance, we conducted a detailed, broadscale study across the tropical savannas of northern Australia on the ecology of three large, sympatric marsupial herbivores (family Macropodidae): the antilopine wallaroo (Macropus antilopinus), common wallaroo (M. robustus), and eastern grey kangaroo (M. giganteus). Using information on species abundance, climate, fire history, habitat, and resource availability, we constructed species' habitat models varying from the level of the complete distribution to smaller regional areas. Multiple factors affected macropod abundance, and the importance of these factors was dependent on the spatial scale of analyses. Fire regimes, water availability, geology, and soil type and climate were most important at the large scale, whereas aspects of habitat structure and interspecific species abundance were important at smaller scales. The distribution and abundance of eastern grey kangaroos and common wallaroos were strongly influenced by climate. Our results suggest that interspecific competition between antilopine wallaroos and eastern grey kangaroos may occur. The antilopine wallaroo and eastern grey kangaroo (grazers) preferred more nutrient-rich soils than the common wallaroo (grazer/browser), which we relate to differences in feeding modes. The abundance of antilopine wallaroos was higher on sites that were burned, whereas the abundance of common wallaroos was higher on unburned sites. Future climate change predicted for Australia has the capacity to seriously affect the abundance and conservation of macropod species in tropical savannas. The results of our models suggest that, in particular, the effects of changing climatic conditions on fire regimes, habitat structure, and water availability may lead to species declines and marked changes in macropod communities.


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Blue whales Balaenoptera musculus aggregate to feed in a regional upwelling system during November–May between the Great Australian Bight (GAB) and Bass Strait. We analysed sightings from aerial surveys over 6 upwelling seasons (2001–02 to 2006–07) to assess within-season patterns of blue whale habitat selection, distribution, and relative abundance. Habitat variables were modelled using a general linear model (GLM) that ranked sea surface temperature (SST) and sea surface chlorophyll (SSC) of equal importance, followed by depth, distance to shore, SSC gradient, distance to shelf break, and SST gradient. Further discrimination by hierarchical partitioning indicated that SST accounted for 84.4% of variation in blue whale presence explained by the model, and that probability of sightings increased with increasing SST. The large study area was resolved into 3 zones showing diversity of habitat from the shallow narrow shelf and associated surface upwelling of the central zone, to the relatively deep upper slope waters, broad shelf and variable upwelling of the western zone, and the intermediate features of the eastern zone. Density kernel estimation showed a trend in distribution from the west during November–December, spreading south-eastward along the shelf throughout the central and eastern zones during January–April, with the central zone most consistently utilised. Encounter rates in central and eastern zones peaked in February, coinciding with peak upwelling intensity and primary productivity. Blue whales avoided inshore upwelling centres, selecting SST ~1°C cooler than remotely sensed ambient SST. Whales selected significantly higher SSC in the central and eastern zones than the western zone, where relative abundance was extremely variable. Most animals departed from the feeding ground by late April.

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A case study is used to demonstrate the application of Geographical Information Systems (GIS) to inform sustainable development. The suitability of the landscape to support tourism accommodation in a Local Government Area (LGA) is modelled by integrating existing datasets, including conservation areas, residential zones, major roads and known locations of tourism operators into a logistic regression framework. By using a data-driven approach an indication of the relative importance of each explanatory variable can be accounted for, therefore informing planners of the importance of different assets. In a region where tourism is reliant upon natural features, this use of information systems in conjunction with quantitative statistical modelling can value-add to existing datasets. The provision of this kind of knowledge is important as it would otherwise not factor into the decision-making process had the datasets been considered independently of each other – a concept that applies to both the public and private sectors.

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The research reported in this paper examined spoken mathematics in particular well-taught classrooms in Australia, China (both Shanghai and Hong Kong), Japan, Korea and the USA from the perspective of the distribution of responsibility for knowledge generation in order to identify similarities and differences in classroom practice and the implicit pedagogical principles that underlie those practices. The methodology of the Learner’s Perspective Study (LPS) documented the voicing of mathematical ideas in public discussion and in teacher-student conversations and the relative priority accorded by different teachers to student oral contributions to classroom activity. Significant differences were identified among the classrooms studied, challenging simplistic characterisations of ‘the Asian classroom’ as enacting a single pedagogy, and suggesting that, irrespective of cultural similarities, local pedagogies reflect very different assumptions about learning and instruction. We have employed spoken mathematical terms as a form of surrogate variable, possibly indicative of the location of the agency for knowledge generation in the various classrooms studied (but also of interest in itself). The analysis distinguished one classroom from another on the basis of “public oral interactivity” (the number of utterances in whole class and teacher-student interactions in each lesson) and “mathematical orality” (the frequency of occurrence of key mathematical terms in each lesson). Classrooms characterized by high public oral interactivity were not necessarily sites of high mathematical orality. In particular, the results suggest that one characteristic that might be identified with a national norm of practice could be the level of mathematical orality: relatively high mathematical orality characterising the mathematics classes in Shanghai with some consistency, while lessons in Seoul and Hong Kong consistently involved much less frequent spoken mathematical terms. The relative contributions of teacher and students to this spoken mathematics provided an indication of how the responsibility for knowledge generation was shared between teacher and student in those classrooms. Specific analysis of the patterns of interaction by which key mathematical terms were introduced or solicited revealed significant differences. It is suggested that the empirical investigation of mathematical orality and its likely connection to the distribution of the responsibility for knowledge generation are central to the development of any theory of mathematics instruction.

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This paper discusses preliminary findings from a sub-set of empirical data collected for a recent NCVER study that explored the geographic dimensions of social exclusion in four locations in Victoria and South Australia with lower than average post school education participation. Set against the policy context of the Bradley Review (2008) and the drive to increase the post-school participation of young people from low socio-economic status neighbourhoods, this qualitative research study, responding to identified gaps in the literature, sought a nuanced understanding of how young people make decisions about their post-school pathways. Drawing on Appadurai’s (2004) concept ‘horizons of aspiration’ the paper explores the aspirations of two young people formed from, and within, their particular rural ‘neighborhoods’. The paper reveals how their post-school education and work choices, imagined futures and conceptions of a ‘good life’, have topographic and gendered influences that are important considerations for policy makers.

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 Australians enjoy a relatively high degree of life quality as judged by comparative international statistics. This chapter reviews the distribution of Quality of Life in Australia by considering both the objective and subjective wellbeing (SWB) of the Australian population. The review begins with an overview of objective circumstances, including income, social support, and life expectancy. It also considers the distribution of trust. Two extant measures of the subjective wellbeing of Australians are then reviewed, and it is revealed that SWB has demonstrated remarkably stable properties over the last 12 years. This chapter provides some insight into the properties of the measures and the theoretical construct of Subjective Wellbeing to explain fluctuations that occur for different components of SWB. Further, this chapter considers the demographic characteristics that are common to Australians with higher and lower SWB and offers a basis of research upon which future measures of population wellbeing can be founded

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Curatorial considerations, aims and objectives:The title for this exhibition (37 ° South to 19 ° North) refers to the Latitude of Melbourne, Australia and Cuernavaca, Mexico.My curatorial objective for making such a reference to the geographical was to invoke a sense of both distance and connection between the two locations of Australia and Mexico and to also create a sense of sharing, not only between our distant landscapes and cultures but also between the feelings and emotions that we all experience in response to the places in which we live out the moments which make up our daily lives.In developing this project I considered the work of more than 35 contemporary Australian photographers and finally selected 15 photographers (including myself). Most of these artists have or have had close connection to Melbourne and to the southern/eastern line of Australian continent. The final selection ranged from Hobart to Maroochydore and one artist who had lived in Melbourne for many years but was now living in Mexico. These photographers (and the specific works) were selected because their long term creative practice captures a sense of location (place and space) with a deep introspective sensibility which I feel offers a viewer a personal and softly spoken vision of some particular aspect of an Australian location, be that exterior landscape or interior place and a sense of unique connection to such places. These images are not documents but rather representations of feelings, stories, memories and dreams which emerge in the milieu of our inhabitants.In selecting the works, careful consideration was also given to diversity of approaches to photographic practice in conjunction to thematic content. Formats and media included black and white, pin hole photography, toy camera, large format (both 4” x 5” and 10”x 8”), phone camera, various digital camera images and other experimental approaches. The local art scene in Cuernavaca is very strong and there is a strong interest in photography. This is partially due to the number of local arts schools and universities which offer studies in photography as well as the political dimension regarding Mexican art in general - as a tool of both political media, reportage and documentary work, photography is a significant medium for many of the people who would be visiting the exhibition. I therefore felt it was important to address the diversity of approaches to the medium which are currently being explored by Australian practitioners.The City Museum of Cuernavaca provided two large walls and some smaller sections of side walls on both the grounds level and the upper level of the main museum galleries for exhibition.The works were arranged with a simple thematic structure. Top level, left to right, then bottom level, left to right starting with images which presented a sense of wilderness and landscape (which were also quite abstract and reductive) to more representational landscape images moving to landscape with small figures (people) emerging within the images (Ash Kerr) to landscapes with larger figures and the emerging presence of man-made elements to urban landscapes and then to interior urban scapes and finally to interior locations with people and finally finishing on the metaphorical image by Harry Nankin of Bogong Moths and the politics of climate change. (It is also interesting to note that the migration path of the Bongong moth matches well the distribution of the artists selected for this project)Broadly speaking the images started outside with broad landscape to intimate interior locations. With these works a great deal of personal content from each photographer was presented. Most artists chose to present 3 large format images while some only presented 2 images. Other graphic and visual elements were considered in the final placement of the images.It must also be noted that the artists selected ranged broadly from very highly established and significant local artists to mid-career/younger establishing artist to some lesser known and emerging artists. From a curatorial perspective I feel this is offers the possibility of what I shall term, a more balanced representation of the local Australian practice and it provides a context in which both established and emerging artists / works must engage on a dialogue, within the exhibition. I believe it also placing the curatorial premise on the strength of the work rather than on whom the artists are and their status. It also supports the younger emerging artists and provides a less formal and predictable outcome for the established artists and for as a collective presentation as a whole.

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The Australasian gannet (Morus serrator) population has increased considerably over the past century, both in New Zealand and Australia. Since 1980, the population in Australian waters has increased threefold, from 6,600 breeding pairs to approximately 20,000 pairs in 1999-2000, a rate of 6% per year. Reasons for the increase in the Australasian gannet population are poorly understood; here we consider the possible effects of recent fluctuations in climatic and oceanographic conditions, and changes in major local commercial fisheries. A significant trend towards more frequent, and stronger, El Niño Southern Oscillation events, warmer summer sea surface temperatures in Bass Strait, increased annual catches and catch per unit effort in the Victorian pilchard (Sardinops sagax) fishery and potential increased discarding of fisheries bycatch may account for at least some of the observed increase in the Australasian gannet population. The potential interactive effects of these factors on prey distribution and abundance and consequently on gannet numbers are discussed.

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Students completing three-year engineering technology and four-year professional engineering undergraduate courses may undertake a number of common study units. To gain an objective understanding of the academic performance characteristics of both student groups in the engineering and technology programs at Deakin University (Australia), a study was  undertaken of close to 9000 unit enrollments. It was found that: overall the BTech withdrawal rate was about 20% higher than for BE students; the rate of withdrawal was significantly different between the two student groups; the grade distribution for completing students was not significantly different between the two groups; the mean final grade was not significantly different between the two student groups; the failure rate was not significantly different between the two student groups; and the overall wastage rate (withdrawn rate plus fail rate) was significantly higher for BTech students. Other related results are also reported.

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Previously, minimal work has been carried out on conulariids due to their rare occurrences and resultant biostratigraphical limitations. The palaeobiogeographical distribution of Permian conulariids suggests that they have a marked preference for cold to cool-water regions, that they are significant indicators for migration patterns, and that they can potentially provide information on the palaeogeographical configuration and movement of terranes. Permian conulariids are found in Australia, India, New Zealand, Pakistan, Iran, Afghanistan, Kashmir, China, Japan, Russia, Germany, Canada, United States of America, and Bolivia. The diversity of Permian conulariids is markedly higher in the polar regions than in the palaeoequatorial region.

Permian conulariid genera include Notoconularia Thomas 1969, Gondaconularia Waterhouse 1986, Cheliconularia Waterhouse 1986, Neoconularia Sugiyama 1942, Calloconularia Sinclair 1952, Diconularia Sinclair 1952, Paraconularia Sinclair 1940, Mesoconularia Boucek 1939 and Conularia Sowerby 1821. This paper describes two new species of conulariids: Diconularia meadepeakensis sp. nov. from the Phosphoria Formation (Guadalupian), Idaho, USA and Paraconularia kazanensis sp. nov. from the Sokian Horizon (?Roadian), Volga Region, Russia.