19 resultados para Bellingshausen Sea, western flank of trough, middle shelf

em Deakin Research Online - Australia


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However derived, predictions of global marine species diversity rely on existing real data. All methods, whether based on past rates of species descriptions, on expert opinion, on the fraction of undescribed species in samples collected, or on ratios between taxa in the taxonomic hierarchy, suffer the same limitation. Here we show that infaunal macrofauna (crustaceans and polychaetes) of the lower bathyal depth range are underrepresented among available data and documented results from Australia. The crustacean and polychaete fauna (only partially identified) of the bathyal continental margin of Western Australia comprised 805 species, representing a largely novel and endemic fauna. Overall, 94.6% of crustacean species were undescribed, while 72% of polychaete species were new to the Australian fauna, including all tanaidaceans, amphipods, and cumaceans, as well as most isopods. Most species were rare, and the species accumulation rate showed no sign of reaching an asymptote with increasing area sampled. Similar data are likely for the largely unexplored bathyal regions. This leads us to conclude that the numbers upon which extrapolations to larger areas are based are too low to provide confidence. The Southern Australian and Indo-West Pacific deep-sea regions contribute significantly to global species diversity. These regions and bathyal and abyssal habitats generally are extensive, but are so-far poorly sampled. They appear to be dominated by taxonomically poorly worked and species-rich taxa with limited distributions. The combination of high species richness among infaunal taxa-compared to better known taxa with larger individuals, higher endemism than presently acknowledged because of the presence of cryptic species, the low proportion of described species in these taxa, and the vast extent of unexplored bathyal and abyssal environments-will lead to further accumulation of new species as more and more deep sea regions are explored. It remains to be tested whether ratios of 10 or more undescribed to described species, found in this study for the dominant taxa and for the deep Southern Ocean and the Indo-West Pacific, are replicable in other areas. Our data and similar figures from other remote regions, and the lack of faunal overlap, suggest that Appeltans et al.'s (Current Biology 22:1-14, 2012) estimate that between one-third and two-thirds of the world's marine fauna is undescribed is low, and that Mora et al.'s (PLoS Biol 9(8):e1001127. doi:10.1371/journal.pbio.1001127, 2011) of 91% is more probable. We conclude that estimates of global species, however made, are based on limited data. © 2014 Senckenberg Gesellschaft für Naturforschung and Springer-Verlag Berlin Heidelberg.

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This paper investigates the channels through which the middle class may matter for consumption growth and development. Determinants of the size and the growth of the middle class are also examined. Using several different middle class measures and a panel of 72 developing countries spanning the period 1985-2006, we find that a larger middle class influences growth primarily through higher levels of human capital investment. We also find that large governments, higher levels of urbanization, greater democracy, ethnic concentration, and sea access are all associated with a larger middle class. © 2011 by Asian Development Bank.

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The experience of urban settlement in the Western District of Victoria suggests that the pattern of growth and decline in small towns is tied to the pattern of land use. This, in turn, is determined by the economic and technological factors which influence farm management and practices. At times, these factors have encouraged urban development and small towns have flourished. For the most part, however, these forces have not been conducive to sustaining long-term growth and prosperity and small towns, have been trapped in a cycle of growth and decline.

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The promotion of closer settlement in the Australian state of Victoria between 1898 and 1914 was viewed as a panacea to many of the problems that beset the state. The region known as the Western District of Victoria was seen as particularly suitable for the application of land re-settlement policy. The study of this region highlights several important features of the closer settlement experiment in Victoria. First, it illustrates how the basic principles of closer settlement were used to further the interests of particular groups. Second, it highlights the flaws in foundations of the Closer Settlement Act which impacted on the settlers chances of success. And thirdly it points to the disastrous implications of policy implementation that paid little attention to the geographical and economic parameters governing the outcome of farming enterprises.

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1.Foraging behaviours of the Australian sea lion (Neophoca cinerea) reflect an animal working hard to exploit benthic habitats. Lactating females demonstrate almost continuous diving, maximize bottom time, exhibit elevated field metabolism and frequently exceed their calculated aerobic dive limit. Given that larger animals have disproportionately greater diving capabilities, we wanted to examine how pups and juveniles forage successfully.
2.Time/depth recorders were deployed on pups, juveniles and adult females at Seal Bay Conservation Park, Kangaroo Island, South Australia. Ten different mother/pup pairs were equipped at three stages of development (6, 15 and 23 months) to record the diving behaviours of 51 (nine instruments failed) animals.
3. Dive depth and duration increased with age. However, development was slow. At 6 months, pups demonstrated minimal diving activity and the mean depth for 23-month-old juveniles was only 44 ± 4 m, or 62% of adult mean depth.
4. Although pups and juveniles did not reach adult depths or durations, dive records for young sea lions indicate benthic diving with mean bottom times (2·0 ± 0·2 min) similar to those of females (2·1 ± 0·2 min). This was accomplished by spending higher proportions of each dive and total time at sea on or near the bottom than adults. Immature sea lions also spent a higher percentage of time at sea diving.
5. Juveniles may have to work harder because they are weaned before reaching full diving capability. For benthic foragers, reduced diving ability limits available foraging habitat. Furthermore, as juveniles appear to operate close to their physiological maximum, they would have a difficult time increasing foraging effort in response to reductions in prey. Although benthic prey are less influenced by seasonal fluctuations and oceanographic perturbations than epipelagic prey, demersal fishery trawls may impact juvenile survival by disrupting habitat and removing larger size classes of prey. These issues may be an important factor as to why the Australian sea lion population is currently at risk.

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This report presents the results of an analysis of three years of tide and meteorological data aimed at delineating the influences of atmospheric pressure, waves, onshore winds and longshore winds on coastal sea levels West of Port Phillip Bay, Victoria« The data was used to develop predictive and hindcasting techniques for meteorological tides on the Otway Coast, using statistical methods, an empirical method and a mathematical model. The nature and magnitude of contributions of the various components of the meteorological tide, and the general variability of monthly and seasonal variations were also studied. It was found that meteorological tides on the Otway Coast can account for significant sea level changes, with the main factors being wind and atmospheric pressure. The wind component of the meteorological tide was found to be approximately twice the pressure component, and longshore winds were found to be more significant than onshore winds for wind setup on the Otway Coast. The meteorological tide models developed enable estimates of wind setup and atmospheric pressure setup on the Otway Coast to be readily computed using data from synoptic charts. The wave setup component could not be separated from the meteorological tide and is included in the wind setup component. The results of the investigation are relevant to the design and maintenance of coastal engineering works, and point to the need for the establishment and operation of coastal management schemes on the Otway Coast.

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 The use of an online diplomatic simulation to increase learning outcomes amongst students of MIddle East Politics. The chapter explores the gains to be had from such collaborative online learning, including the increased depth and breadth of knolwedge gained, the defeat of ethnocentricity, high levels of stduent engagement and the changing role of the teacher in this role play as learners become more self-directed.

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How is the rise of China perceived in the West? Why is it often labelled as ‘threat’ and/or ‘opportunity’? What are the implications of these China imageries for global politics?

Taking up these important questions, this ground-breaking book argues that the dominant Western perceptions of China’s rise tell us less about China and more about Western self-imagination and its desire for certainty. Chengxin Pan expertly illustrates how this desire, masked as China ‘knowledge’, is bound up with the political economy of fears and fantasies, thereby both informing and complicating foreign policy practice in Sino-Western relations. Insofar as this vital relationship is shaped not only by China’s rise, but also by the way we conceptualise its rise, this book makes a compelling case for critical reflection on China watching.

Knowledge, Desire and Power in Global Politics is the first systematic and deconstructive analysis of contemporary Western representation of China’s rise. Setting itself apart from the mainstream empiricist literature, its critical interpretative approach and unconventional and innovative perspective will not only strongly appeal to academics, students and the broader reading public, but also likely spark debate in the field of Chinese international relations.