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131.
《Geoforum》2017
In this paper we examine two central concepts of urban metabolism (‘system boundaries’ and ‘flows’), and explore how to approach them as a means to politicise urban metabolism research. We present empirical findings from two case studies of waste management, in Mexico City and Santiago de Chile, looking at: the materiality of waste flows, the actors involved in them, and how waste flows relate to issues of environmental justice. We argue that urban metabolism, as a methodology to understand urban sustainability, has the potential to produce knowledge to trigger urban transformations, and to analyse the social, political and environmental aspects of waste management in urban areas. 相似文献
132.
To contribute to establishing a historical baseline for future evaluations of the environmental quality of the Ría de Vigo (NW Spain), we report metal contents determined in eight gravity cores obtained at representative locations in 1990 - before the installation of any wastewater treatment plants - and in fractions thereof that were obtained by the BCR sequential extraction method. The results suggest that early diagenesis had been influenced by both hydrodynamic conditions and organic matter input (the latter especially in areas devoted to mariculture), and that anthropogenic inputs had also affected the concentrations and between-fraction distribution of Cu, Pb, Zn and other metals in surficial sediments. 相似文献
133.
A new Lower Triassic (Induan) Jerus Limestone locality in northwest Pahang,Peninsular Malaysia: Conodont fauna,depositional and tectonic settings 下载免费PDF全文
Ian Metcalfe 《Island Arc》2016,25(2):126-136
Limestones exposed north of Raub, Pahang, Malaysia, and sandwiched between the Bentong‐Raub Suture Zone and the westernmost margin of the Sukhothai Arc terrane, yield a late Dienerian (late Induan) conodont fauna. The co‐occurrence of Neospathodus dieneri Sweet (morphotypes 1, 2 and 3) and Neospathodus pakistanensis Sweet represents the Neospathodus dieneri morphotype 3 sub‐zone of the Neospathodus dieneri Zone. The sampled limestones are interpreted as the northwards extension of the Jerus Limestone which crops out near Cheroh and Jerus villages, significantly extending the known outcrop of the Jerus Limestone northwards. The Jerus Limestone is interpreted as hemipelagic and formed in a foredeep or forearc setting on top of the accretionary complex formed by eastwards subduction of the Palaeo‐Tethys during the Lower to Middle Triassic. 相似文献
134.
Isolated Archosaur teeth from the green sandstone capping the Coralline Limestone (Bagh Group) of the Narmada valley: Evidence for the presence of pre‐Late to Late Maastrichtian abelisaurids in India 下载免费PDF全文
Guntupalli V.R. Prasad Vishal Verma Pooja Grover Rajkumari Priyadarshini Ashok Sahni Ranjit S. Lourembam 《Island Arc》2016,25(6):410-420
Recent field prospecting in the Cretaceous sequences of the lower Narmada valley has led to the discovery of three isolated archosaur teeth from the upper part of marine Cretaceous rocks of the Bagh Group. The specimens were recovered by surface prospecting from an oyster‐bearing green sandstone bed occurring at the top of the Coralline Limestone (Coniacian) from a site near Phutibawri village, Dhar District, Madhya Pradesh, India. Of the three teeth recovered from this horizon, two are identified with abelisaurid dinosaurs and the third one with an indeterminate crocodile. The abelisaurid teeth conform to the premaxillary and maxillary tooth morphology of Majungasaurus and Indosuchus. Earlier reports of abelisaurid dinosaurs from India are from the Upper Cretaceous (Maastrichtian) Lameta Group of Jabalpur, Pisdura (Central India) and Balasinor (Western India) and Upper Cretaceous (Late Maastrichtian) Kallamedu Formation (South India). As no associated age diagnostic fossils are found, the specimens described here are considered to represent pre‐Late to Late Maastrichtian age based on the known ages of the underlying and overlying formations. The new finds, therefore, document stratigraphically the oldest occurrence of abelisaurid dinosaurs known from the Indian subcontinent. 相似文献
135.
Mohamed-Montassar Ben Slama Amara Masrouhi Mohamed Ghanmi Mohamed Ben Youssef Fouad Zargouni 《Comptes Rendus Geoscience》2009,341(7):547-556
In the northern part of Tunisia, close to Testour/Slouguia, new observations and updated biostratigraphy make it possible to highlight the relation between the Triassic saliferous mass and the surrounding Mesozoic beds (T. M.). Near the (T. M.) boundary, the formations observed consist dominantly of Triassic evaporites reworked in the Early and Late Albian deep-water sedimentary deposits. Throughout the studied area, Jurassic rocks are absent. We propose to interpret the Chitana-Ed Djebs structure originally emplaced as gravitational stretch masses in a passive margin in the same way as the salt bodies of widespread salt province in the Gulf of Mexico. A reconstructed schematic position of the Chitana-Ed Djebs salt body displays a scenario of setting of the salt mass on a submarine palaeo-slope. Moreover, the starting clues of the paroxysmal event of the Late Mesozoic tectonic inversion clearly fossilized through the discordance of the Middle Eocene–Early Lutetian limestone on the Albian series. 相似文献
136.
We Are All Makers: The Method of Keyword Selection in Teaching and Learning Human Geography 总被引:1,自引:0,他引:1
Abstract Geographers continue to engage in public debate “inside the Beltway” by participation within and through federal agencies and through the National Research Council. Several examples illustrate the level and kind of this engagement, which has been concentrated on environmental and spatial data and analysis themes. Most professional geographers have the opportunity to engage in this form of public debate through participation in the activities of the National Research Council. The level of this participation has been surprisingly strong, given the small size of the community of professional geographers, and has helped to shape both U.S. and international research agendas relevant to geographic research. Participation, however, is concentrated in a few programs and individuals, raising questions about the sustainability of geography's voice in this public activity. 相似文献
137.
In view of a globalizing marketplace and the continual need for market intelligence, firms seek venues in which to access cost effective, functional information. Significant sources of such knowledge, especially in tacit form, can be found within temporary clusters: international trade fairs. This article explores how firms in the solar photovoltaic (PV) industry use educational programs held during a trade fair as a means of information acquisition and exchange, providing a new angle to research on the economic geographies of these events, especially in terms of learning processes. Specifically, it analyzes how firms use educational programs to access remote knowledge (i.e., tacit information unavailable in a local context) in these temporary, spatially confined environments. Analyses of firm-level survey data gathered at a recent solar industry trade fair revealed that there is a significant effect of educational program participation on accessing remote knowledge. The results provide evidence that firms participate in trade fair educational programs to access remote knowledge that is critical to international success. Key Words: educational programs, knowledge exchange, remote knowledge, trade fairs. 相似文献
138.
Bi Tié Albert Goula Emile Gneneyougo Soro Williams Kouassi Bernard Srohourou 《水文科学杂志》2013,58(6):1067-1080
Résumé Le changement climatique est une réalité qui affecte plusieurs variables climatiques dont les précipitations. Néanmoins, son impact sur les évènements extrêmes et en particulier sur les pluies journalières extrêmes n'est pas encore certain car peu de travaux y ont été consacrés en Afrique de l'Ouest. Dans ce contexte, il a été proposé de détecter d'éventuels tendances et ruptures dans les propriétés statistiques (moyenne, variance) des pluies journalières extrêmes à l'aide de tests statistiques locaux et régionaux. Pour détecter ces changements, les indices caractérisant la pluie maximale journalière annuelle (PJmaxan), le nombre annuel de jours de pluie dépassant 50 mm (NJsup50) et la contribution des pluies dépassant 50 mm dans les cumuls annuels (R(PJsup50/Pan)) ont été définis. L'analyse de 44 postes pluviométriques en Côte d'Ivoire sur la période 1942–2002 ne montre pas de changement généralisé ni en moyenne, ni en variance. Toutefois, en subdivisant la Côte d'Ivoire en régions climatiques homogènes, des tendances à la baisse ont été observées dans les régions IV (au Nord) et II (au Sud-Est). Editeur Z.W. Kundzewicz; Assistant editeur G. Mahé Citation Goula, A.B.T., Gneneyougo Soro, E., Kouassi, W. et Srohourou, B., 2012. Tendances et ruptures au niveau des pluies journalières extrêmes en Côte d'Ivoire (Afrique de l'Ouest). Hydrological Sciences Journal, 57 (6), 1067–1080. 相似文献
139.
D. LE GOURIÉRÈS 《水文科学杂志》2013,58(3):301-313
ABSTRACT In this paper, the author relies on Darcy's law and on an hypothesis formulated from experimental considerations to establish a semi-empirical formula for the calculation of the discharge of partially penetrating wells of free aquifer sunk in isotropic soils. This relatively simple relation applied to 27 cases studied under an experimental design or numerical computations, reveals itself to have an unexpected accuracy. Starting from previous formula, the author establishes another one for partially penetrating wells bored in anisotropic soils. 相似文献
140.
Résumé Un modèle hydrologique global a été calé sur des épisodes pluvieux de durée très variable (de un à plus de dix jours). Les épisodes pris en compte sont ceux qui sont encadrés par au moins un jour sec et ne provoquant pas de déversement du barrage. L'entrée de ce modèle comprend la pluie moyenne du bassin versant et l'indice des précipitations antérieures de Kohler & Linsley. Les expressions du modèle hydrologique du début et au cours de la saison humide, selon un seuil du cumul des pluies de la saison depuis le début de l'automne, sont de la forme non linéaire polynomiale du second ordre. Le modèle s'est montré performant dans l'évaluation de la lame ruisselée malgré le faible nombre de postes pluviométriques (un) pour la taille du bassin versant de 48 km2. L'absence d'autres postes pluviométriques sur le bassin versant n'a pas permis d'étudier la précision du modèle en considérant une pluie moyenne sur le bassin versant au lieu de la pluie uniquement au site du Barrage Ghézala. Citation Mathlouthi. M. & Lebdi, F. (2010) Modélisation de la relation pluie–ruissellement par durée d'épisode pluvieux dans un bassin du nord de la Tunisie. Hydrol. Sci. J. 55(7), 1111–1122. 相似文献