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A significant metamorphosis of channel form occurred on the lower Macdonald River between 1949 and 1955; width and width-depth ratio increased and depth, sinuosity and weighted mean per cent silt-clay in the channel perimeter decreased. The channel has remained unstable since 1955, exhibiting frequent variations in bed elevation and a recent period of minor channel contraction followed by slight enlargement. Since 1946 there has been an increase in summer and annual rainfall and an abrupt, upward shift of the annual series flood frequency curve. As a result an increased proportion of the total sediment load of the river is now being transported as bed-material load. The change in sediment load is a result of greater stream competence and the consequent reworking of sandy sediment temporarily stored within the channel as benches. The observed channel changes are a quasi-adjustment to the increased flood and bed-material load discharges.  相似文献   
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A number of investigations have been undertaken by the New South Wales Water Resources Commission to determine the regional and compound effects of large scale extractive industries on the stability of the Hunter River, New South Wales. Sedimentologic studies of bed material suggest that the Hunter River upstream of Denman has an armoured gravel bed that is immobile during regulated releases from Glenbawn Dam but is disrupted by moderate but less than bankfull flows. Annual bedloadyields have been computed by the bedload rating-flow duration technique for five river gauging stations. Approximate sand and gravel budgets for selected reaches of the Hunter River demonstrate that the present annual extraction rate from temporary sediment storages within the channel greatly exceeds the transport rate upstream of Denman and is approximately equal to the transport rate downstream of Denman. River degradation is imminent if extractive industries continue operating in the channel of the Hunter River  相似文献   
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ANDREW HEROD† 《对极》1991,23(4):385-402
This paper analyzes the responses to two separate closures of a large glass manufacturing plant in Clarksburg, West Virginia, to examine how geography has been integral to the conduct of local political practice in this community. When the plant, by far the local area's largest manufacturing employer, first closed in 1979 the state and local government put together a considerable package of incentives to attract a purchaser for the facility. However, although glass production continued, the plant was again closed in 1987 after a corporate takeover. In response to this second closure the characteristically pro-business Governor of West Virginia initiated an almost $650 million lawsuit against the plant's new owners. The plant's union leaders on the other hand collaborated with city government officials and local business interests to constrain community opposition to the closure. The paper argues that this paradoxical situation, of actors taking up positions contrary to those which an ageographical class analysis would have predicted, was the result precisely of their locality dependence in the face of mobile capital.  相似文献   
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A trial, monitored release on the Wingecarribee River over 27 days had a peak discharge below the Wingecarribee Dam of 1090 ML/d, which had a flow duration of 0.95 per cent. Morphological impacts on 29 km of channel below the dam included bank erosion, concentrated neck overflow, bed degradation and channel widening at recent cutoffs, sedimentation in weir pools and overbank flow, particularly at discharges greater than 800 ML/d. Prolonged operational releases at bankfull discharge (400–800 ML/d) will have the greatest morphologic impacts and should be avoided. Pulses which dissipate stream power over a broad, well-vegetated floodplain should be incorporated in the operational release policy, provided such pulses are phased to facilitate channel and vegetation recovery.  相似文献   
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The article investigates homemaking processes of mature age gay men living in a provincial Australian town. All too often the experience of older gay men living in non-metropolitan centres has slipped the attention of scholars. The article draws on interview data collected in Townsville (Queensland, Australia) from ten men over 40 years of age who self-identified as gay. These men were asked to explain why they live in Townsville, their understanding of home, and if they understand Townsville as home. We investigate the spatialised understandings of home articulated by these gay men, focusing on two mutually constituted geographical scales: Townsville-as-home and house-as-home, including the material objects within domestic space. For older gay men to call a provincial town home is an ongoing, complex process of reconciling multiple and contradictory subjectivities across different geographical scales. How older gay men constitute Townsville-as-home provides important insights about both non-heterosexual life in provincial centres and how to conceptualise home—as a paradoxical space, contested site, and as multiscalar.  相似文献   
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This article scrutinizes the merits of holding a referendum over UK membership of the EU. It queries the assumption that direct democracy can somehow resolve the longstanding Europe question in British politics. To do this, the analysis traces the existence of an exceptionalist approach to the EU within Britain, now associated with re‐negotiating UK membership in the shadow of a referendum. The article argues that the prospects for a radical reconfiguration of the UK's treaty obligations are slim, thereby increasing the risk of a vote to withdraw. Yet withdrawal would be the opposite of a simple solution to the Europe question. Political and economic interests dictate lengthy politicking over a highly complex post‐Brexit settlement revisiting free movement of goods, services, capital and people. Such negotiations undermine any mooted cathartic benefits of a popular vote, while Eurosceptics will remain dissatisfied in the event of a yes, a result likely to further destabilize the Conservative Party. Consequently, the simplicity and decisiveness that a referendum—particularly one that spurns the EU—promises is merely a mirage as relations with the EU necessarily form part of an enduring British political conversation.  相似文献   
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