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31.
The emergence of water markets has heralded the prospect of increased efficiency in the use of the resource for extractive purposes. However, water markets have not encompassed all elements of demand for the resource. Notably, demands for the environmental public goods provided by river flows have not been revealed in markets. State Governments have instituted regulations requiring ‘environmental flows’ to be quarantined from the market allocation process. This policy has triggered negative responses from irrigators and conservationists. Lobby groups have found that the process of determining environmental flows is a prospective site for rent seeking. To avoid policy being driven by rent seeking, information on the costs and benefits of environmental flows is useful. Whereas the costs of environmental flows are readily assessed through reference to market data on irrigators’ surpluses foregone, the benefits must be estimated through the use of non‐market, stated preference valuation techniques. These techniques — including contingent valuation and choice modelling — remain controversial. Some argue that they should not be used on ethical grounds. Others argue that they cannot be used on technical grounds. These arguments are discussed in this paper, using the context of the water policy debate. The evidence is that stated preference techniques are being used, and applications have been performed in Australia in the context of riverine health. However their use remains restricted relative to the scale of the Australian natural resource management task. Some possible explanations for this limited up‐take are provided along with some suggested ways forward.  相似文献   
32.
以《影梅庵忆语》、《浮生六记》等为代表的“忆语”文是清代文人记录私人琐屑生活的回忆性文字,然其文体应归属于小说还是散文,学界仍颇有分歧。而文体分类的主要依据是艺术表现和内容特征。本文认为“忆语”文在内容上具有纪实性、生活化、文人性、私密性等特点,当属于回忆性言情散文。  相似文献   
33.
本文为作者代表中国考古学会在"南水北调中线工程考古发现与研究学术研讨会"上的讲话:一、为什么要保护好文物;二、考古学在文物保护中的位置;三、考古学如何在文物保护中发挥作用;四、此次会议取得的成果。  相似文献   
34.
Questions of mobility, settlement pattern, and their relation to economic organization and resource use are central to ongoing work in central-western Argentina. Here we analyze geographic patterns in the distribution of 178 human bone carbonate δ18O samples, 46 human tooth enamel carbonate δ18O samples, and 48 water δ18O samples from throughout the Andean Cordillera and Monte Desert and evaluate their implications for prehistoric mobility and economy. We confirm and refine previous generalizations regarding a highland/lowland dichotomy in water δ18O values and show that the range of human carbonate δ18O values generally reflect available water sources. While there is little within-lifetime change in patterns of water use, we show that most individuals have stable isotope signatures consistent with water use from multiple areas or areas other than where they were ultimately interred. These data indicate high levels of residential mobility, and we conclude by discussing their implications for our understanding of regional prehistory.  相似文献   
35.

In comparison with the teaching of most other geography topics, where fieldwork can be conducted relatively easily and seminars can be based on some pre-existing knowledge and first-hand experience of the issues, the range of resources and approaches available to tutors teaching the geography of development is necessarily more limited. Tutors often have to rely more heavily on 'top-down' teaching and more passive learning approaches, such as using videos, slides and lectures. While students may gain a theoretical understanding of development concepts, issues and problems, they may be left without a deeper 'experience' of such material. This paper describes a practical workshop designed to communicate to students the idea of 'appropriate technology'. The workshop enables students to actively 'experience' a development concept rather than simply understand it in theory. It tests comprehension and understanding, through the application of a concept to real examples, stimulates discussion and debate, and draws upon problem-solving and critical thinking skills.  相似文献   
36.
Bones treated at low temperature do not present major modifications although, macroscopically, boiled bones may be distinguished from unboiled ones as they are smoother, lighter and more transparent. Such observations should correspond to textural modifications at a nanometric level and should depend on boiling time. In this study, contemporary human bones, boiled during various time intervals, were characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and nitrogen adsorption (BET). The results were used to estimate the boiling time in four archaeological samples (Neolithic bones from Malalmuerzo cave, Spain). It is concluded, comparing Neolithic bones to contemporary ones and from the textural characterization at a nanometrical level, that two of the archaeological bones were boiled and that they were boiled for less than 6 hours.  相似文献   
37.
This article describes seismic hazards, including fault rupture, liquefaction, landslides, and site amplification, using Los Angeles as a case study. Water supply simulation results are presented for a 7.8 MW earthquake on the San Andreas Fault. Severe water losses are shown after 24 h, with nearly 2,700 locations of pipeline damage and a 66% decrease in normal water service. The water supply system was modeled with and without reservoirs that have been removed from service to meet water quality standards. The results show that opening the disconnected reservoirs immediately after a serious earthquake is an effective strategy for emergency response.  相似文献   
38.
Analysis of detailed geomorphological mapping enables a sequence of glacial events to be established. An ice sheet whose source was to the west of the area of study is shown, by the suites of fluvioglacial landforms produced, to have down‐wasted in situ; meltwaters escaped beneath or through the ice, moving uphill across certain areas. Finally, a sub‐aerial drainage system was established and outwash terraces were spread down valley.  相似文献   
39.
The article investigates how humans ‘networked’ wet nature and how this affected the shaping of Dutch society. First, it takes a grand view of Dutch history and describes how wet network building intertwined with the shaping of the Dutch landscape, its economy and its polity. Second, it investigates the specific challenges of wet network building—integrating potentially conflicting uses of water into one design—for the case of the national fresh water supply network (1940–1971). Finally, it discusses ecological damage, emerging new risks and cultural patterns related to wet network building.  相似文献   
40.
Abstract

Quantitative methods of content analysis have become established in most subfields of political science, but remain relatively unutilized in studies of political theory, despite the exclusive focus of that subfield on textual sources. This article develops a variation of content analysis—termed usage analysis—and employs it to resolve a standing debate in scholarship on Cicero's political theory regarding the synonymy of the major Latin terms for the state (civitas and res publica). The resulting distinction between these concepts then informs an exposition of Cicero's ideal state not as the Roman Republic itself or the mixed constitution alone, but as a universal, everlasting political society supported by justice, a mixed constitution, and active citizenship.  相似文献   
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