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41.
Adriana García Brian G. Jones Bryan E. Chenhalland Colin V. Murray-Wallace 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):507-518
The palaeobiota from a middle to late Holocene succession in Tom Thumbs Lagoon, N.S.W., Australia, reflects a range of environmental conditions caused by sea-level changes and active estuarine sedimentation. At the base of the succession (~ ?0.4 m AHD) a thin bed, containing molluscs dated at 6.7 ka B.P. by radiocarbon and amino acid racemisation, and foraminifers is indicative of open estuarine conditions. From +0.35 m AHD towards the top of the sequence the charophyte Lamprothamnium succinctum occurs in subrecent deposits. This species is characterised here by statistical measurements, and new characters are described and illustrated. The charophytes record a drop in sea level and the establishment of a lower salinity artificial wetland. The investigation has also established that decalcification in charophytes can be related to acidification produced by the release of organic acids, aggravated after 1928 by anthropogenic pollution. 相似文献
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Gilbert J. Price Michael J. Tyler Bernard N. Cooke 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):171-182
Systematic collecting from fluvial late Pleistocene deposits from the Darling Downs, southeast Queensland, Australia, has led to the recovery of the first fossil frogs from the region, ail from the Myobatrachidae, a family of ground dwelling and burrowing frogs. The most common species recovered, Limnodynastes tasmaniensis, is extant on the Darling Downs. The fossil taxa include species whose extant populations inhabit arid zones(Limnodynastes sp. cf. L. spenceri), montane forests (Kyarranus spp.), and open woodlands (Neobatrachus sudelli), and indicate the existence of a mosaic of habitats during the Pleistocene. The absence of the Hylidae (tree frogs), a family common throughout the Darling Downs today, may be explained by a taphonomic bias that favours non-arboreal forms. Alternatively, hylids may have been rare or absent on the Darling Downs during the Pleistocene. 相似文献
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Colin Mcleay 《Geographical Research》1997,35(1):40-46
This paper provides a critical analysis of the cultural and arts policies released by the Keating Labor government of the early 1990s and the current Howard Coalition government. While official definitions of Australian national identity promoted multiculturalism, analysis of Creative Nation, Labor's 1994 cultural policy, and recent statements from the Coalition, exposes the partiality of recent constructions. Both Labor and the Coalition's constructions of identity were based on an economism that was linked to traditional, masculine myths of egalitarianism and ‘mateship’. Such constructions show that neither party has embraced multiculturalism to the degree suggested by policy rhetoric. 相似文献
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Colin Palmer 《International Journal of Nautical Archaeology》2009,38(2):314-330
Weatherliness is widely considered to have been an important ability for ancient sailing vessels, yet little firm experimental or theoretical data on the matter is available. However, by drawing on a variety of sources of model-test data and trials of full-scale replicas, it is possible to establish a general picture of what might have been possible. It appears that while ancient sailing vessels may have been capable of modest windward performance in moderate conditions and with a freshly-cleaned hull, this capability quickly disappeared as the hull became fouled and/or the wind and sea conditions deteriorated.
© 2008 The Author 相似文献
© 2008 The Author 相似文献
49.
Scott Orford Colin Rallings Michael Thrasher Galina Borisyuk 《Transactions (Institute of British Geographers : 1965)》2009,34(2):195-214
This paper considers the impact of distance to polling station upon electoral turnout. Using polling station level data from a London borough, it examines three types of election – parliamentary, European and local elections – over a twenty year period. The UK is notable among western liberal democracies for its relatively large turnout gap – the percentage point difference between turnout at elections for the Westminster parliament compared to that for other institutions, including local councils and the supra-national European parliament. This research considers the hypothesis that in high information, high salience elections for the national parliament the costs of voting associated with travelling to a polling station to vote in person are perceived as either low or insignificant but that in low information, low salience elections, those costs are perceived as higher and may act as a deterrent upon voting. A series of multi-level models consider the relationships between the dependent variable, percentage turnout, and a range of independent variables, including socio-economic characteristics, marginality as well as the spatial context. We show that there is indeed a relationship between distance and voter turnout, and other spatial and contextual variables, which are stronger for the lower salience European and local elections than for the higher salience national elections. Hence we conclude that the local geography of the polling station can have a significant impact on voter turnout and that there should be a more strategic approach to the siting of polling stations. 相似文献
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