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151.
Acid sulphate soils form when iron pyrite oxidises to sulphuric acid on atmospheric exposure, lowering soil pH below 4. In the Richmond River estuary, northern New South Wales, flood mitigation, drainage works and floodplain excavations have augmented acid sulphate soil formation by increasing pyrite availability for oxidation. These engineering works have facilitated the transport of acidified water and have impeded recovery from tributary acidification. The increased frequency and duration of acidification are associated with elevated concentrations of inorganic monomeric aluminium and dissolved iron, and major iron hydroxide precipitation, with deleterious effects on exposed aquatic biota and habitat. Fish kills and an outbreak of epizootic ulcerative syndrome (EUS) have been recorded from acidified sites in the estuary. 相似文献
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G.J.R. LINGE 《Geographical Research》1995,33(1):116-132
The sovereignty of the bleak Kurile islands, off northern Japan, has long been the subject of a bitter stand-off between Russia and Japan. This has not only prevented their signing a post-1945 Peace Treaty but has retarded the flow of official financial assistance and corporate investment funds across the few hundred kilometre-wide Sea of Japan. As a result the reconstruction of the Russian Far East has been made more difficult, thus exacerbating the economic and social hardship there. Examples like this should cause us to reflect on the dangers of making simplistic explanations about the spatial organisation of economic activity as well as the need to rediscover political geography. 相似文献
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Bénédicte Zimmermann 《European Review of History》1998,5(1):9-23
Concepts of unemployment or of the labour market are not abstract, but develop from each society's own particular logic. Taking the examples of Germany and France at the end of the nineteenth century, it is possible to see how these concepts were constructed in specific national contexts, and how they were then used in practice. This analysis leads us to rethink current ideas about work and unemployment, and to ask what their future will be in a united Europe. 相似文献
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Daniel R. White 《European Legacy》1998,3(3):76-79
From Monad to Man: The Concept of Progress in Evolutionary Biology. By Michael Ruse (Harvard University Press, 1997), x + 628 pp., $49.95 cloth. 相似文献