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431.
432.
Christian Kerschner Christina Prell Kuishuang Feng Klaus Hubacek 《Global Environmental Change》2013,23(6):1424-1433
Peak Oil, which refers to the maximum possible global oil production rate, is increasingly gaining attention in both science and policy discourses. However, little is known about how this phenomenon will impact economies, despite its apparent imminence and potential dangers. In this paper, we construct a vulnerability map of the U.S. economy, combining two approaches for analyzing economic systems, i.e. input–output analysis and social network analysis (applied to economic data). Our approach reveals the relative importance of individual economic sectors, and how vulnerable they are to oil price shocks. As such, our dual-analysis helps identify which sectors, due to their strategic position, could put the entire U.S. economy at risk from Peak Oil. For the U.S., such sectors would include Iron Mills, Fertilizer Production and Transport by Air. Our findings thus provide early warnings to downstream companies about potential ‘trouble’ in their supply chain, and inform policy action for Peak Oil. Although our analysis is embedded in a Peak Oil narrative, it is just as valid and useful in the context of developing a climate roadmap toward a low carbon economy. 相似文献
433.
Ayrton F. Martins Tibiriçá G. Vasconcelos Danielle M. Henriques Carla da S. Frank Armin König Klaus Kümmerer 《洁净——土壤、空气、水》2008,36(3):264-269
This study was carried out to evaluate the occurrence of the fluoroquinolone antimicrobial agent ciprofloxacin (CIP) in the effluent of the Hospital of the Federal University of Santa Maria (HUSM). Measured environmental concentrations (MECs) of CIP in the hospital wastewater, both before (P1) and after (P2) cesspit/filter system treatment (CFTS), were determined by means of solid phase extraction and reversed‐phase liquid chromatography with fluorescence detection (LC‐FLD) and reversed‐phase liquid chromatography with mass spectrometric detection (LC‐MS/MS). The MECs (n = 7 daily composed samples) were 19 to 155 μg L–1 (average: 54 ± 21 μg L–1) and 32 to 99 μg L–1 (average: 65 ± 45 μg L–1) in P1 and P2, respectively. No relevant removal was observed from P1 to P2. In a worst case scenario, the final effluent was regarded as MECs of surface water. These MECs were generally 5 to 20,000‐fold higher than what was previously known. If the present data is drawn on to form a model of the situation in developing countries, the picture provides a first rough indication that the environmental risk associated with the use and emission of pharmaceuticals into the environment in developing countries might be higher than in developed countries. 相似文献
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436.
Matthew Coggon Caryl Ann Becerra Klaus Nüsslein Karen Miller Richard Yuretich Sarina J. Ergas 《Geochimica et cosmochimica acta》2012
Biological reduction of iron-sulfate minerals, such as jarosite, has the potential to contribute to the natural attenuation of acid mine drainage (AMD) sites. Previous studies of AMD attenuation at Davis Mine, an abandoned pyrite mine in Rowe Massachusetts, provided evidence of iron and sulfate reduction by indigenous bacteria. Jarosite is a large component of the sediment at Davis Mine and may play a role in AMD attenuation. In this study, microcosms were constructed with groundwater and sediment from Davis Mine and amended with glycerol, nitrogen and phosphorus (GNP) and naturally formed natrojarosite. Over time, higher total iron, sulfate, pH and sodium concentrations and lower oxidation–reduction potentials were observed in microcosms amended with GNP and jarosite, compared with unamended microcosms and killed controls. Geochemical modeling predicted jarosite precipitation under microcosm conditions, suggesting that abiotic processes were unlikely contributors to jarosite dissolution. SEM imaging at the jarosite surface showed microbial attachment. Microbial community composition analysis revealed a shift to higher populations of Clostridia, which are known to reduce both iron and sulfate. The results show that jarosite may be utilized as an electron acceptor by iron and/or sulfate reducing bacteria at Davis Mine and its presence may aid in the attenuation of AMD. 相似文献
437.
Klaus Schlichte 《Geoforum》2012,43(4):716-724
Non-state war actors have only recently become a subject of study in political geography while other social sciences such as political anthropology, sociology and political science have addressed this subject in their respective conceptual language. This article, drawing on empirical research on war actors in 14 countries and using data on a sample of 80 such groups, advocates using the language of political sociology, and in particular that of Max Weber and Norbert Elias, to study this form of contestation. It presents some major findings of an empirical analysis built on these conceptualizations. Written from a political science perspective it tries to link up to the discourse in other social sciences, especially in political geography. 相似文献
438.
An incomplete skull (SMNS 12352) from the Norian (Late Triassic), found at the same locality (Pfaffenhofen, Germany) as Procompsognathus triassicus, has previously been attributed to either a theropod or a crocodylomorph. The specimen is partially embedded in matrix and, therefore, was CT scanned so that the concealed portion could be visualized and a 3D model could be printed by means of rapid prototyping. Mainly based on the separation between the nasal and the antorbital fossa, the skull likely pertains to an indeterminate basal crocodylomorph (non-Crocodyliformes), which is, however, distinct from Saltoposuchus connectens. 相似文献
439.
Klaus Frantz 《GeoJournal》2012,77(6):777-790
Several North American metropolitan areas including Albuquerque, El Paso and Seattle in the U.S., and the Canadian urban areas of Montreal and Vancouver, are characterized by Indian reservations situated either within or on the outskirts of these cities. This type of Indian reservation or reserve within metropolitan areas has been the subject of limited geographical research, and is nowhere as manifest as in Metro-Phoenix. Three reservations obstruct the otherwise unlimited growth of Arizona??s capital. This phenomenon is most striking in the eastern regions of Phoenix where, until the end of the 1980s, the almost exclusively rural, agrarian Salt River Indian Reservation formed a physical and cultural barrier to urban development, preventing metropolitan sprawl beyond a clearly marked boundary. Continued urban pressures have led to changing land uses, effectively hollowing out this embankment or barrier, which has caused a profound change in the reservation. Both the Salt River and Gila River Indian reservations maintain large tracts of irrigated agricultural land, but the transformation that converted farms to suburbs off the reservation is now changing the reservation itself. In fact, this change actually began more than a hundred years ago with the Anglo-American colonization of what is today Arizona??s central region. 相似文献
440.
Eva Leitholdt Christoph Zielhofer Stefanie Berg‐Hobohm Katharina Schnabl Britta Kopecky‐Hermanns Jens Bussmann Joachim W. Hrtling Klaus Reicherter Katrin Unger 《Geoarchaeology》2012,27(1):88-104
The Central European watershed passes through the southern Franconian Jura in Bavaria, Germany. This principal watershed divides the Rhine/Main catchment and the Danube catchment. In the early Middle Ages, when ships were an important means of transportation, Charlemagne decided to connect these catchments by the construction of a canal known as the Fossa Carolina. In this paper, we present for the first time 14C data from the Fossa Carolina fill and document a high‐resolution stratigraphic record of the Carolingian and post‐Carolingian trench infilling. Our results provide clear evidence for peat layers in different levels of the trench infill, suggesting a chain of ponds. However, the majority of these peat layers yield mid‐Medieval and younger ages. The period of major peat growth was during the Medieval climatic optimum. Therefore, our preliminary results do not prove the use of the trench during Carolingian times. However, first results from the reconstruction of the Carolingian trench bottom support the hypothesis that the Fossa was primarily planned as a navigable chain of ponds and not as a continuous canal. In the eastern part of the trench, a dam is located that was postulated in former studies to be part of a barrage for supplying the Carolingian canal with water. New 14C data indicate much younger ages and do not support the Carolingian barrage concept. 相似文献