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171.
John Taylor 《The Australian geographer》2003,34(3):355-370
Population estimates are rarely constructed for ecological regions. The recent establishment of a Desert Knowledge Cooperative Research Centre (CRC) generates a need for such estimates. This paper obliges by presenting Indigenous and total population projections for the Australian desert to 2016. The desert is found to be a region of relatively low population growth in national terms, contrary to the experience of many other parts of non-metropolitan Australia where population decline is prevalent. Also noted is the markedly different growth observed for the Indigenous and non-Indigenous components of the desert population, with the former projected to increase much more rapidly over time. It is likely that virtually all of the increase in the desert population over the next 15 years will arise from natural increase among Indigenous peoples. As a consequence, the Indigenous share of the regional population is projected to rise from 20 per cent in 2001 to 24 per cent by 2016, with attendant consequences for social and economic policy. 相似文献
172.
R.J. Johnston 《The Australian geographer》1997,28(1):29-37
Having been invited to contribute an external view of Australian geography, I concluded that such a task was impossible—that geographers elsewhere do not have a general view of Australian geography. I maintain that this is neither surprising nor significant, setting the argument within the context of a discipline fragmented along four major cleavage lines. Because of these cleavages, most geographers (like most other academics) work in small intellectual communities which are necessarily ‘parochial’: as a consequence, the discipline is characterised by a series of parts that do not make a coherent whole. 相似文献
173.
利用NCEP/NCAR逐月SLP再分析资料,通过复经验正交函数展开(CEOF),借助其第1模态恢复场研究了1952-1998年期间南极绕极波动的年代际变化和传播特征。结果表明,东南太平洋是研究南极绕极波动(ACW)的关键区,并由此定义东南太平洋ACW活动指数(EPAI)。相关分析揭示了秋季EPAI与次年中国夏季降水有着密切的关系,当秋季EPAI出现异常正位相时,即当东南太平洋SLP距平出现正异常时,次年春、夏季澳大利亚高压偏强,进而由于越赤道气流的增强及西太平洋副高调整引起次年夏季中国出现华南多雨、江淮少雨的雨型分布,证实了ACW是另一个与中国夏季降水异常有密切关联的年际变化强信号。 相似文献
174.
Goniomya sp. ind., and Goniomya sp. ind. aff. G. kasanensis (Geinitz), described by Diener (1903) from the Permian of the Central Himalayas, are shown to belong to Undulomya. Goniomya uhligi Holdhaus, 1913, thought by Holdhaus to be of Jurassic age, is also regarded as an Undulomya and con‐specific with or closely related to the above species. Cosmomya egregaria Holdhaus, 1913, the type species of Cosmomya Holdhaus, 1913, which comes from the same locality as Undulomya uhligi, is regarded as congeneric with Palaeocosmomya Fletcher, 1946. Palaeocosmomya therefore, becomes a synonym of Cosmomya, but is retained at the subgeneric level. The evidence now available indicates that Undulomya uhligi and Cosmomya egregaria are of Late Permian age. Undulomya and Cosmomya are regarded as two quite distinctive genera which also differ from the Jurassic genus Goniomya, in which species of both have hitherto often been included. Undulomya and Cosmomya have so far been recorded from Australia, India, Madagascar and the Soviet Union and Cosmomya, in addition, from Greenland. 相似文献
175.
利用NCEP/NCAR再分析资料、Hadley中心海温资料及CMAP降水资料等,通过亚澳季风联合指数挑选异常年份,对东亚夏季风和澳洲冬季风强度反相变化特征进行研究。结果表明,当东亚夏季风偏强、澳洲冬季风偏弱时,南北半球中低纬地区都出现了复杂的异常环流系统。在热带地区对流层低层,西北太平洋为异常反气旋式环流系统所控制,与南太平洋赤道辐合带的异常反气旋环流在赤道地区发生耦合,形成赤道异常东风,而在南北印度洋上则存在两个异常气旋式环流系统。在这两对异常环流之间的海洋性大陆地区,出现赤道以南为反气旋环流而赤道以北为气旋式环流。在东亚季风区,东南沿海的东侧海洋上存在反气旋异常,中国东南地区受异常反气旋西南侧的东南风影响。此外,澳洲北部受异常西风影响。这就形成了东亚夏季风偏强、澳洲冬季风偏弱的情形,从而东亚夏季风和澳洲冬季风活动出现了强弱互补的变化特征。当东亚夏季风偏弱、澳洲冬季风偏强时,南北半球的环流特征则出现与上述相反的环流特征。总体而言,当东亚夏季风偏强、澳洲冬季风偏弱时,东亚—澳洲季风区在南北半球呈现出不同的气候异常分布特征,即北半球降水北少南多、气温北高南低,南半球降水西多东少、气温西高东低。 相似文献
176.