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This paper explores the various dimensions of integration that need consideration in developing appropriate institutional arrangements for integrated water resource management (IWRM), drawing upon both IWRM and spatial planning sources. As a result, a framework of integration in IWRM is set out. This is then used to consider the strengths and weaknesses of the new spatial planning system in England, and its potential to contribute to IWRM activities that are being developed, partly in response to the European Union Water Framework Directive. From this analysis it is argued that, taken overall, spatial planning is well placed to meet these challenges and it could in fact play a much more central role than is currently envisaged. An alternative model for IWRM in England is set out which sees the new river basin management plans as integral, rather than parallel, to the spatial planning system.  相似文献   
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Fifty scapolites have been analysed spectrographically for numerouselements. Average concentrations (p.p.m.) were as follows: B25, Be 9-3, Ga 33, Ti 82, Li 56, Cu 4-4, Zr 59, Mn 57, Sr 1,800,Pb 45, Ba 120, Rb 20. The following were seldom or never detected:Cr, Ni, Co, Mo, Sn, V, Sc, Ag, Y, La. The major elements Ca,Na, K were also determined. The distribution of the trace elementscan be explained by isomorphous substitution, but no detailedcorrelation of trace elements with each other or with majorelements was found. Refractive indices were determined and the relation betweenaverage index and per cent Me was examined: correlation waspoor, which may in part be attributed to analytical error. Examination of scapolite parageneses shows that scapolite characteristicallyoccurs in the upper amphibolite facies or the pyroxene hornfelsfacies: it is not restricted to these and may occur in any faciesfrom zeolitic to granulitic and in any hornfels facies. Theelements generally concentrated in scapolite include Ca, Na,C, Cl, S, H, B, Be, Li, Sr, Pb. The presence of C, Cl, S, Htestify to genesis in the presence of high partial pressureof CO2, Cl2, SO3, H2O (or related compounds), that is in pneumatolytic,pegmatitic, or hydrothermal environments. The concentrationof B, Be, Li can also be attributed to these conditions. The source of the elements concentrated in scapolite must inpart be common rocks. In a limited contact zone, the nearbymagma supplied some elements, but where regional scapolitizationhas taken place the presence of magma is less clear. Many commonrocks or rock series contain all the necessary constituents,but some particular conjunction of conditions is necessary forscapolite to form, or it would be more common.  相似文献   
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Deposition of till by melt-out was described as early as a hundred years ago, and today the criteria which provide evidence to support an interpretation of melt-out till are available. The most important criteria are (P1) the presence of unlithified, sorted and stratified sediments within or interstratified with the till(s). (P2) the presence of a statistically preferred orientation of stone axes closely related to ice-flow condition, and (P3) a configuration of till with a recognizable textural or lithological property closely related to the configruation of englacial debris with regard to P1. Based on P1 and P2 and on regional aspects, tills composing ridges transverse to the dircetion of ice flow are interpreted as mult-out till and flow till. The interpretation of till genesis must be based on the balnce of probability, as absolute proof is unrealistic in most cases.  相似文献   
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Analysis of 24 reference materials for B, Sm, Gd, H, has been carried out over several years, using prompt gamma neutron activation analysis. The results are compared with values obtained by other workers, in order to better calibrate these standards. In most cases our results of repeated analysis of RMs show agreement with results from other laboratories, using various methods. A djustments to working values are proposed in some cases.  相似文献   
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The paper presents an account of the occurrence, petrography,mineralogy, and geochemistry of several intrusions of adamellite-porphyrite,an early member of the New England Bathylith (N.S.W.). The rockis composed of phenocrysts of quartz, andesine, hornblende,biotite, augite (and minor orthopyroxene) which are set in afine-grained quartzofeldspathic groundmass. Compositions ofsilicate phenocrysts (which reveal widespread evidence of cataclasis)accord with coexisting phases of an assemblage appropriate tointermediate rocks. Xenolith mineralogy is similar to equivalentminerals occurring as phenocrysts. The recalculated bulk compositionof a rock represented by the modal andesine, hornblende, biotite,augite, and magnetite of the adamellite-porphyrite is similarto the composition of a biotite–diorite; the compositionof the quartzo-feldspathic groundmass plots in the low-meltingregion of the NaAISi3O8-KAISi3O8-SiO2-H2O system. Evidence ispresented to indicate a hybrid origin for the adamellite-porphyritewhereby disrupted biotite-diorite was invaded and mixed withlow-melting silicic alkalic liquid.  相似文献   
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Coastal upwelling meanders and filaments are common features off eastern ocean boundaries. Their growth is reinvestigated herein using a nonhydrostatic three-dimensional model and a reduced-gravity model, with the objective of assessing contributions from two mechanisms that emerge in the nonhydrostatic regime. The first mechanism is caused by the vertical projection of the Coriolis force in the momentum equation. It is found that the vertical Coriolis force often acts as a restoring force against numerical damping off eastern ocean boundaries and thus enhances the growth of meanders and filaments. The second mechanism arises from unstable ocean stratification when the cold upwelled water intrudes seaward over the warm layer. The unstable stratification, albeit transient, further enhances the growth of meanders and filaments. It is concluded that although nonhydrostatic effects do not change our understanding of how meanders and filaments grow, the realism can be enhanced using a nonhydrostatic model insofar as meanders and filaments off eastern ocean boundaries are concerned.  相似文献   
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当前GIS广泛采用的空间数据模型不足以满足时态GIS发展的需要。该文探讨时态GIS所需的、可操作性时空数据模型,并且以土地利用和交通发展的时空相互作用为例,说明如何设计和实施相关的时空数据模型,用于支持发展时态GIS。  相似文献   
20.
城市群体移动研究通常以网格为空间分析单元,其分析存在可塑性面积单元问题(modifiable area unit problem,MAUP),目前的研究缺乏对不同大小的网格面积单元所忽略的城市群体移动规律的定量分析结论。对城市空间进行有限的不同大小的等间距格网划分并对城市群体移动忽略部分进行分析,发现格网内群体移动量随格网大小线性递增,格网间的群体移动量随格网大小线性递减,并以提取城市重要位置的空间分布和属性特征的不一致为例,表明应对忽略的短距离移动予以重视,避免决策上的偏差。与此同时,不同格网划分大小情况下格网内的移动量在住宅用地、工业用地上被忽略程度较为严重,建议根据实际研究的目的采取不均匀划分空间格网方法,避免过多忽略群体移动。  相似文献   
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