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41.
胡浩 《人文地理》2004,19(2):84-87
本分析了关中地区城镇生活水价现状和问题,得出了城镇生活水价是不可持续的结论,即水价低于供水生产成本,水价结构不合理。在探讨可持续水价的调整原则的基础上,提出了价格杠杆调节关中生活水价的措施,包括:逐步把水价调整到成本水价以上的水平,并调整水价结构,使之能反映供水成本和水资源价值;实行累进加价制度,对超定额用水征收高水价;实施季节性水价等。  相似文献   
42.
ABSTRACT Water is a resource that both unites and divides people in the Upper Hunter Valley of New South Wales, where many communities are facing the prospect of large‐scale open‐cut coalmining developments on productive mixed use land, or already live in proximity to mines and power stations. This article analyses conflicts over a proposed coal mine at Bickham in the Upper Hunter Valley, by contrasting the various protagonists' discourses of water scarcity, supply, and connectivity. It examines the ways in which the terms of opposition are narrowed to the arena of state and industry supported science and economic development, marginalising other cultural values and environmental ethics that are integral to opponents' discourses. Opponents have achieved some measure of success through contestation of the uncertain science of hydrological modelling, bolstered by the context of drought and increasing public acceptance of climate change science.  相似文献   
43.
Modern technology lends itself to holistic exploration and widely accessible outreach. New technology allows scientists studying our planet either from space or deep under the seas, to explore and reveal both natural and cultural resources that have previously escaped our scrutiny. However, the use of these new technologies is expensive and often the exclusive tool of industrial research. Yet, these new technologies can lead the way to greater collaboration, better science and more public access. In 2003 and 2004, a landmark project, combining government agencies, industrial technology and outreach set new standards in collaborative scientific exploration. The project focused on six shipwrecks at depth in the Gulf of Mexico. The questions posed by the project illuminate how science and industry can collaborate to produce remarkable results. The papers presented in this issue form a model for deepwater exploration.  相似文献   
44.
The existence of gendered knowledge has been identified as a significant feature of Indigenous Australian culture, and the importance of considering the implications of gendered environmental knowledge in collaborative cross-cultural natural resource management has been highlighted. There is a lack of case studies that demonstrate how Indigenous women's knowledge and laws can be provided for in resource management contexts. From collaborative research with Anmatyerr women in central Australia, we discuss the implications of gender bias in relation to gendered knowledge in natural and cultural resource management, with a specific focus on Anmatyerr women's involvement in providing inputs about the cultural values of water within water allocation planning processes. This research highlights Anmatyerr women's own perspectives of their roles in contemporary contexts and identifies the existence of cultural change and continuity in relation to rights and responsibilities around water.  相似文献   
45.
Ongoing excavations at Olduvai Gorge, Tanzania, reveal tremendous variability among stone artifact assemblages across the Plio-Pleistocene Olduvai Lake Basin during Bed I and lower Bed II times. Theoretically, stone artifact traces of Oldowan hominin land use are determined by the distribution of larger mammal carcasses and arboreal refuge from predation as well as proximity to stone material sources.  相似文献   
46.
J. J. Adams  S. Bachu 《Geofluids》2002,2(4):257-271
Physical properties of formation waters in sedimentary basins can vary by more than 25% for density and by one order of magnitude for viscosity. Density differences may enhance or retard flow driven by other mechanisms and can initiate buoyancy‐driven flow. For a given driving force, the flow rate and injectivity depend on viscosity and permeability. Thus, variations in the density and viscosity of formation waters may have or had a significant effect on the flow pattern in a sedimentary basin, with consequences for various basin processes. Therefore, it is critical to correctly estimate water properties at formation conditions for proper representation and interpretation of present flow systems, and for numerical simulations of basin evolution, hydrocarbon migration, ore genesis, and fate of injected fluids in sedimentary basins. Algorithms published over the years to calculate water density and viscosity as a function of temperature, pressure and salinity are based on empirical fitting of laboratory‐measured properties of predominantly NaCl solutions, but also field brines. A review and comparison of various algorithms are presented here, both in terms of applicability range and estimates of density and viscosity. The paucity of measured formation‐water properties at in situ conditions hinders a definitive conclusion regarding the validity of any of these algorithms. However, the comparison indicates the versatility of the various algorithms in various ranges of conditions found in sedimentary basins. The applicability of these algorithms to the density of formation waters in the Alberta Basin is also examined using a high‐quality database of 4854 water analyses. Consideration is also given to the percentage of cations that are heavier than Na in the waters.  相似文献   
47.
During the last few decades, Cape Town Castle has been extensively renovated. Parallel to this, a series of archaeological excavations were undertaken under the auspices of different institutions. During the course of these, it became clear that one specific site needed to be approached in a rather unorthodox way. This site, the main well situated in the centre of the previous headquarters of the Dutch East India Company at the Cape of Good Hope, was filled with water. Owing to its inaccessibility and other constraints, which made the application of adapted excavation techniques necessary, the need arose to call in the assistance of a diver-archaeologist. This article describes the approach to fieldwork undertaken in the Kat well during 1989 and 1999 and some of this feature's structural details.  相似文献   
48.
Human transport of bones with high food values, and destruction of bones with low density values are the traditionally invoked explanations of the frequencies of bones in archeological contexts. The manner in which these two explanations have been used suggests archaeologists assume the explanations to be independent of one another. The transport explanation is operationalized as the modified general utility index (MGUI) of Binford, and the destruction explanation is operationalized with measures of bone density. Statistical correlation of the MGUI with bone density, while weak, indicates that many high utility bones have low density values while many low utility bones have high density values. Because low density bones tend to be destroyed more readily than high density bones, inferences of human utility strategies derived from bone frequencies and based on the MGUI may be inaccurate. The utility strategies suggested by three archaeofaunas are compared to bone density, and two of these faunas are shown to potentially be the result of differential destruction and not human transport as measured by the MGUI.  相似文献   
49.
Salt-accumulating renders are usually applied in several layers with different specific properties of moisture transport. An extensive experimental programme was carried out to establish a relationship between those properties of individual layers and the performance of combined systems on a salt-laden substrate. Each of the 20 renders was characterized separately in absorption and drying tests, vacuum saturation tests, dry cup tests, mercury intrusion porosimetry, and ultrasound wave velocity measurements. Each of the 12 combined render systems was applied on a brick, which was then saturated with a concentrated NaCl solution by free capillary uptake. Subsequently the assembly was closed at the bottom and subjected to an accelerated drying test (50° C and 15% relative humidity). Moisture and salt profiles over the depth were taken regularly during 1 month. The results reveal very different degrees of effectiveness and levels of risk for the substrate, which are related to the moisture transport properties.  相似文献   
50.
Pore water needs to be extracted from rocks with low permeabilities to allow the major ion concentrations in the pore water to be estimated. Compressing a rock is the most widely used method of extracting the pore water. However, ion concentrations have been found to change during compression in previous studies, and the mechanisms involved in such ion concentration changes have not yet been fully assessed. In this study, two natural rocks and four artificially prepared samples were compressed, and changes in the chloride ion (Cl?) concentrations as the compression pressure increased were investigated. Mechanisms that could have caused the changes observed were then assessed. The Cl? concentrations in squeezed water decreased as the pressure increased if the sample contained a significant amount of smectite. The strong dependence of Cl? concentration on the amount of smectite indicated that smectite played an important role in decreasing the Cl? concentration. The dilution of the pore water with interlayer water from the smectite appeared to be the dominant mechanism involved in the decrease in Cl? concentration found in a Kunigel‐V1 sample, because dilution of the pore water with interlayer water quantitatively explained the decrease in the Cl? concentration. The filter effect caused by the anion exclusion effect did not appear to be a dominant mechanisms in our case. However, Cl? concentration decrease found in natural rocks could not be fully explained by dilution with interlayer water, so other mechanisms must be involved the phenomenon in natural rocks.  相似文献   
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