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71.
The Krafla geothermal system is located in Iceland's northeastern neovolcanic zone, within the Krafla central volcanic complex. Geothermal fluids are superheated steam closest to the magma heat source, two‐phase at higher depths, and sub‐boiling at the shallowest depths. Hydrogen isotope ratios of geothermal fluids range from ?87‰, equivalent to local meteoric water, to ?94‰. These fluids are enriched in 18O relative to the global meteoric line by +0.5–3.2‰. Calculated vapor fractions of the fluids are 0.0–0.5 wt% (~0–16% by volume) in the northwestern portion of the geothermal system and increase towards the southeast, up to 5.4 wt% (~57% by volume). Hydrothermal epidote sampled from 900 to 2500 m depth has δD values from ?127 to ?108‰, and δ18O from ?13.0 to ?9.6‰. Fluids in equilibrium with epidote have isotope compositions similar to those calculated for the vapor phase of two‐phase aquifer fluids. We interpret the large range in δDEPIDOTE and δ18OEPIDOTE across the system and within individual wells (up to 7‰ and 3.3‰, respectively) to result from variable mixing of shallow sub‐boiling groundwater with condensates of vapor rising from a deeper two‐phase reservoir. The data suggest that meteoric waters derived from a single source in the northwest are separated into the shallow sub‐boiling reservoir, and deeper two‐phase reservoir. Interaction between these reservoirs occurs by channelized vertical flow of vapor along fractures, and input of magmatic volatiles further alters fluid chemistry in some wells. Isotopic compositions of hydrothermal epidote reflect local equilibrium with fluids formed by mixtures of shallow water, deep vapor condensates, and magmatic volatiles, whose ionic strength is subsequently derived from dissolution of basalt host rock. This study illustrates the benefits of combining phase segregation effects in two‐phase systems during analysis of wellhead fluid data with stable isotope values of hydrous alteration minerals when evaluating the complex hydrogeology of volcano‐hosted geothermal systems.  相似文献   
72.
The author seeks to analyse the repercussions and consequences of the Pinochet affair for Chilean domestic politics. He explains how the legacy of seventeen years of authoritarian rule has shaped the deep divisions within Chilean society regarding the prosecution of the Chilean former dictator in the London courts. Chile is an incomplete democracy and Pinochetism is very much alive in Chile today.
The author is very critical of the role played by the current Chilean government and political class, for their behaviour during the affair. In granting a special mission to the General which gave him immunity and later supported his legal case after initial hesitation, the government has shown confusion that has not advanced the case for full democratization and justice in Chile. The ambiguous behaviour of the political class during the episode has discredited its prestige in the eyes of public opinion. Chilean society, according to the author, has missed an opportunity to advance justice and the dignity of the country.  相似文献   
73.
Optimal Allocation of Land between Productive Use and Recreational Use   总被引:3,自引:0,他引:3  
Abstract This paper is an inquiry into the optimal allocation of time and natural areas to recreational uses, which have the feature of being a pure and continuous public good. We address this issue with a comprehensive approach. A static rational general equilibrium framework is developed in which heterogeneous agents allocate land and time endowments between alternative uses. This modeling has important advantages. First, Pareto‐optimal and voluntary‐contribution equilibrium allocations are obtained in a unified set‐up. Second, the suboptimality result of the decentralized equilibrium, the free‐rider problem on the provision of this nonexcludable public good, and different mechanisms to return the economy to its first‐best are analyzed. Finally, a methodological critique is made of some empirical literature, and it is suggested that our theoretical microeconomic‐based structure seems to be a suitable starting point for empirical research.  相似文献   
74.
ABSTRACT This paper surveys recent evidence on the determinants of (national and/or foreign) industrial location. We find that the basic analytical framework has remained essentially unaltered since the early contributions of the early 1980s while, in contrast, there have been advances in the quality of the data (more firm and plant level information, geographical disaggregation, panel structure, etc.) and, to a lesser extent, the econometric modeling. We also identify certain determinants (neoclassical and institutional factors) that tend to provide largely consistent results across the reviewed studies. In light of this evidence, we finally suggest future lines of research.  相似文献   
75.
Land fragmentation can be an important drawback for the development of rural areas. Due to the small size of the units, land management and planning are difficult from both the private and the public point of view. In some regions of Europe, land fragmentation can lead to the collapse of land-based activities such as agriculture and forestry. This process triggers land abandonment, which causes social, economic and environmental problems. Traditional interventions such as land consolidation have not worked because of the scale of land fragmentation, which leads to huge transaction costs. New planning instruments and governance structures for land management that balance the relations between property rights, management and labour force can be developed, in order to avoid the problems of land fragmentation. In this paper, we present two innovative examples of land management and governance structures for dealing with land fragmentation in rural areas of Galicia northwestern Spain. They were able to combine the use of individual and common property rights to make land use more sustainable, instead of trying to change land ownership. The new governance structures helped to increase efficiency and sustainability of the land use by, for example, increasing labour productivity, clarifying property rights and diminishing land abandonment.  相似文献   
76.
77.
This essay examines how hermeneutic philosophy, particularly Gadamer's, recovers rhetoric, less as the art of speaking well than as a statement of a truth of the sensus communis, that which communicates veracious content through argumentation. This is the sense in which Gadamer acknowledges the ubiquity of rhetoric and hermeneutics as components of linguisticity (Sprachlichkeit). Conceived in the context of non-methodical wisdom and phronesis, Gadamer's rehabilitated rhetoric is concerned with pragmatics and ethics. Rhetoric is no longer viewed as a technique of verbal manipulation and becomes relevant for dialogic communication. Gadamer thus joins the Habermasian criticism of formalized reason that is detached from values. Both of them reject instrumental reason, because it has colonized communicational reason. However, since Gadamer's view of rhetoric has also been criticized by Habermas and Ricoeur their objections cannot be overlooked in a discussion of his hermeneutics. The essay concludes with a brief consideration of the implications of the debate on rhetoric, hermeneutics, and communication for the twenty-first century.  相似文献   
78.
ABSTRACT We use disaggregated data on Chilean plants, and the Chilean input–output table to examine the impact of agglomeration spillovers on total factor productivity (TFP). In common with previous studies, we find evidence for intraindustry spillovers, but none for general cross‐industry spillovers. This picture changes when we take vertical industry relations into account. There are important productivity spillovers from plants in upstream industries. Interestingly, a similar effect cannot be found from plants in downstream industries. The number of plants in these sectors has no effect on plant‐level TFP, just as the number of plants in other industries that are neither important upstream suppliers nor downstream customers also has no effect.  相似文献   
79.
El Mirón is a large cave in the Cantabrian Cordillera of northern Spain that presents a long archaeostratigraphic sequence radiocarbon-dated by over 60 assays to between 41,000 and 2000 BP. The sediments, collected from four areas within the cave and sieved-washed with fine wire meshes, contain microvertebrate remains of fish, frogs, lizards, birds and mammals, of which the latter are most abundant. Preliminary taphonomic analysis suggests that the microvertebrates were naturally collected by owls and (less) small carnivores. Small mammal assemblages are useful for palaeoenvironmental reconstruction because they are linked to particular habitats and are sensitive to environmental changes. The small mammals from El Mirón are ideal for this because sample sizes are large, bone preservation is good, and the stratigraphic sequence is long. In this paper we reconstruct the late Quaternary environments in the Cantabrian region of Spain using small-mammal assemblages from El Mirón Cave. On the basis of the ecologic adaptations of this suite of fauna, the majority still extant, we have identified seven habitat types, which are plotted through time. The evolution of the small mammal assemblages at El Mirón reveals seven major climatic shifts that correspond closely to the climatic changes recognized in the Iberian Peninsula during the last 41 kyr.  相似文献   
80.
Stone boiling is one of the principal cooking methods used by hunter-gatherer societies. The present paper proposes behavioral and organizational inferences as to how stone boiling was incorporated into hunter-gatherer subsistence practices through an examination of a shallow-basin hearth in an Early Magdalenian level (c. 15,500 14C B.P.) of El Mirón Cave, Cantabria (northern Spain). Exploratory analysis of spatial patterns of archaeological remains (bones, lithic artifacts, and fire-cracked rocks) and use-life analysis of fire-cracked rocks demonstrate that the hearth was used and maintained during visits of humans who preyed mainly on ibex and red deer near the site. The relative accessibility of these ungulates and cost-induced technology of stone boiling suggest the implication that stone boiling was employed to maximize the energy and nutrition obtained from carcasses of these game taxa under the circumstance of resource intensification.  相似文献   
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