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61.
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Initiatives aimed at protecting aquatic ecosystems often prove difficult to implement—particularly in water‐stressed, semi‐arid regions where the demand for water for human consumption is high. This article reports on an investigation of the factors that shaped the development and implementation of policies for aquatic ecosystem protection in the Oldman River Basin (ORB), a crucial watershed in semi‐arid southern Alberta. The analysis reveals critical cultural and historical considerations that confront those attempting to protect and restore aquatic ecosystems in the ORB and highlights specific factors that influence implementation of measures to protect it. In addition to the most basic consideration—demand for water exceeds supplies—eight specific factors that influenced aquatic ecosystem protection in this region are identified and evaluated. These include (1) clarity of actors’ roles/ jurisdictional responsibilities; (2) communication; (3) definition of key terms; (4) funding and organizational capacity; (5) leadership; (6) legal standing; (7) data and monitoring; and (8) public education. We argue that while these factors are important, critical cultural and historical considerations that influence water policy in the province also must be addressed in any efforts to protect aquatic ecosystems in southern Alberta.  相似文献   
63.
During the study of a large number of archaeological glass fragments, manganese‐rich inclusions in leached layers were observed in a limited number of cases. This phenomenon occurs only in black‐coloured leached layers. Since the formation mechanism of such manganese‐rich inclusions is still unclear, a combination of several analytical techniques was used in order to investigate this phenomenon and, more specifically, to obtain more information on (a) the composition and morphology of the inclusions, (b) the chemical state of Mn and (c) the 3D morphology of the inclusions. A mechanism that might explain the formation of these inclusions is proposed.  相似文献   
64.
Current analogical data used to infer prehistoric human bone breakage rely on a plethora of experimental hammerstone‐broken bovid bone sets. Several criteria have been argued to be diagnostic of bone breakage by humans, among which the most important are: a specific range of broken specimens bearing percussion marks, a specific distribution of different percussion mark types, metric properties of notches, differential notch type distribution, and the angle of oblique breakage planes. The present work shows that those properties derived from the breakage of bovid bones cannot be universally applied to all types of animals. As an example, here it is experimentally demonstrated that hammerstone‐broken equid bones (with different thickness and structural properties compared to bovid bones) show different values in all these variables and some of them overlap with criteria documented in bones broken by static loading. This suggests that the agents of equid bone breakage are more difficult to identify, and that the number of variables that can be successfully used to that end is smaller than in bovid bones.  相似文献   
65.
ABSTRACT. This article focuses on the recent Mexican controversy about the legal status of the indigenous population and the nature of nationalism, which is linked to recent constitutional amendments and new policy strategies. Changes in legislation and policy are examined in the context of a widespread economic and political crisis of the populist regime after 1982, which radically affected the previous indigenist discourse; but they are also seen as having been motivated by Indian demands and mobilisations against the official vision of citizenship as a function of cultural homogeneity and mestizaje. The article analyses the implications of the new constitutional amendments and the heated debates that they have provoked among different political actors, including indigenous organisations. In particular, it examines two areas of disagreement. The first concerns the multiple meanings of multiculturalism – as a threat of fragmentation and fundamentalism, a new form of state control or a strategy for indigenous national participation and empowerment. The second concerns the definition and levels of implementation of indigenous political autonomy. Negotiation over such disagreements, leading to inclusive citizenship, constitute a great challenge for ethnic intellectuals and theoreticians of Mexican nationalism.  相似文献   
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We use a combination of rock magnetism (anisotropy of magnetic susceptibility, AMS) and magnetic polarity to characterize cave deposits and as a proxy for sedimentary fabric. In three localities at the Atapuerca archaeological site (Galeria, Gran Dolina and Sala de los Cíclopes), magnetic foliation (Kmax/Kint) is always greater than lineation (Kint/Kmin), consistent with a primary, depositional, sedimentary fabric. Our results, although preliminary, reveal a higher degree of anisotropy in autochtonous deposits compared to allochthonous deposits, possibly indicative of a higher hydrodynamic regime in the former. At two localities the magnetic lineation (Kmax) defines a cluster, which is thought to be antipodal to the palaeocurrent direction. Hence we are able to retrieve palaeoflow directions in deposits that otherwise lack any other sedimentary structure. We conclude that AMS is a powerful tool for determining the hydrodynamic character of depositional environments in cave sediments at the Atapuerca archaeological site. A better understanding of the depositional environment and how sedimentation occurred allows reconstruction of the karst evolution and ultimately a better definition of human interaction with the environment.  相似文献   
68.
A group of Copper Age shaft‐hole axes from Caput Adriae (northeastern Italy, western Slovenia and northwestern Croatia) manufactured using meta‐dolerite have been analysed for major and trace elements. All the samples show magmatic textures and well recognizable relicts of primary mineralogical phases. Petrographic observations suggest an ophiolitic provenance of the protolithic source(s) while geochemical data indicate that the original magmas originated in a fore arc or pre arc tectonic setting. Strong similarity has been found with several lithotypes from the Banija Ophiolite Complex (Croatia), here indicated as the most probable source area. Considering the available archaeometric data about shaft‐hole axes found in northern Italy and Caput Adriae in comparison to those of axe blades discovered in the same area, it emerges that there is a utilization of different rock types, the source of which appears to be quite close to the discovery sites. In the investigated area the shaft‐hole axes are largely made from ophiolitic‐related rocks which are associated with copper deposits. Consequently there may have been a relation between the localization of the geological sources of shaft‐hole axes and the development of metallurgical activities.  相似文献   
69.
In Sri Lanka, gender and national identities intersect to shape people's mobility and security in the context of conflict. This article aims to illustrate the gendered processes of identity construction in the context of competing militarised nationalisms. We contend that a feminist approach is crucial, and that gender analysis alone is insufficient. Gender cannot be considered analytically independent from nationalism or ethno‐national identities because competing Tamil and Sinhala nationalist discourses produce particular gender identities and relations. Fraught and cross‐cutting relations of gender, nation, class and location shape people's movement, safety and potential for displacement. In the conflict‐ridden areas of Sri Lanka's North and East during 1999–2000, we set out to examine relations of gender and nation within the context of conflict. Our specific aim in this article is to analyse the ways in which certain identities are performed, on one hand, and subverted through premeditated performances of national identity on the other hand. We examine these processes at three sites—shrines, roads and people's bodies. Each is a strategic site of security/insecurity, depending on one's gender and ethno‐national identity, as well as geographical location.  相似文献   
70.
Several parts of Binh Phuóc Province, southern Vietnam, suffer from degraded soils and vegetation as a result of both natural erosion of weak mud rocks and sandstones and intensive human activity, especially through land clearing for agriculture on unstable slopes, deforestation, and abandonment of poor farmland. The underlying cause of this land degradation has been the farming habits of migrants of varying ethnic groups who have settled in the area since 1980. The indigenous farming knowledge of these people and the role of that knowledge in soil erosion were examined by a series of household surveys. They enabled farming practices to be related to ground cover established from a 2002 Landsat 7 ETM (Enhanced Thematic Mapper), and erosion data from a series of erosion bridge measurements. A GIS (Geographical Information System) approach was piloted as a means of identifying areas vulnerable to erosion. This could then be combined with the understanding of farming practices to reveal the relative roles of farmer behaviour, crop cover, and slope and soil characteristics in the erosion process. Land use, local people's knowledge and economic realities are the main factors, as well as natural conditions, that drive this land degradation.  相似文献   
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