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81.
Abstract Semi-arid landscapes are vulnerable to cultivation, overgrazing and climate variability, although it is difficult to identify the relative significance of these three factors. In the South African Karoo, the ‘desertification debate' seeks to explain a change to more shrubby vegetation in heavily grazed areas. We examine these issues in catchments where farm reservoirs provide sediment stores with 137Cs, 210Pb, geochemical and mineral magnetic signatures. Rainfall data and stocking numbers are reported and current erosion rates are estimated. Sediment accumulation in the reservoirs increases between 1935 and 1940, probably due to rises in the frequency of rainfall events of >25mm day. Significant increases in sedimentation rates (×8) occur during rain-fed wheat cultivation. In an uncultivated catchment, sediment yields remain relatively high and reflect increases in erosion from hillslopes, colluvial storage, and cultivated land sources. Gully systems have acted as transport routes rather than sediment sources over the last ~70 years. Badland erosion rates average ca. 50t ha?1 yr?1. At Ganora, their development in the 1920s strongly influences peak sedimentation between 1970 and 1980. Any delay between badland initiation and increased sediment yield appears to be a function of landscape connectivity. Recovery following disturbance is occurring slowly and is likely to take >100 years. De-stocking and better management systems are reducing erosion rates but may be offset by increases in rainfall intensity. 相似文献
82.
David I. Kertzer Darrett B. Rutman Sydel Silverman Andrejs Plakans 《Historical methods》2013,46(3):119-128
Abstract Mainstream geographical information systems techniques and packaged geographical information systems software are often inappropriate in historical contexts because they use geographical coordinates as a framework around which all other information is organized as “attribute data,” whereas in history locations are often the least certain part of our knowledge. A new and general architecture for documenting administrative units and organizing historical statistics is detailed, which prioritizes named entities and explicit semantic relationships such as “IsPartOf,” while holding coordinate data where available. This architecture is easily aligned with the recent development of geo-semantics by information scientists, meeting the formal requirements for a geo-spatial ontology, but was originally developed to enable the systematic computerization of traditional historical reference works, notably Frederick Youngs’ Guide to the Local Administrative Units of England. 相似文献
83.
Philip I. Buckland Erik Eriksson Johan Linderholm Karin Viklund Roger Engelmark Fredrik Palm Patrik Svensson Paul Buckland Eva Panagiotakopulu Johan Olofsson 《Journal of archaeological science》2011,38(2):345-351
Environmental change has a human dimension, and has had so for at least the last 10 000 years. The prehistoric impact of people on the Arctic landscape has occasionally left visible traces, such as house and field structures. More often than not, however, the only evidence available is at the microscopic or geochemical level, such as fossil insect and seed assemblages or changes in the physical and chemical properties of soils and sediments. These records are the subject of SEAD, a multidisciplinary database and software project currently underway at Umeå University, Sweden, which aims to create an online database and set of tools for investigating these traces, as part of an international research infrastructure for palaeoecology and environmental archaeology. 相似文献
84.
Samples of Roman thin‐walled ware from Segesta (northwestern Sicily), dating back to the early Imperial period, were studied by optical microscopy (OM) and Neutron Activation Analysis (NAA). Up to now, this class of Roman fine tableware has only occasionally been evaluated archaeometrically. Nevertheless, numerous production centres are believed to have been simultaneously active in the western Mediterranean area. Petrographic and chemical data seem to be in agreement with the archaeological hypothesis of local manufacture in Segesta for most of the analysed samples, through a comparison with kiln wasters and local raw materials. The effectiveness of thin‐section petrography for determining the provenance of such a tiny tempered class of pottery and the integrated use of two different grouping procedures (petrography and chemistry) were also tested. 相似文献
85.
86.
Robert J. Losey Vladimir I. Bazaliiskii Sandra Garvie-Lok Mietje Germonpr Jennifer A. Leonard Andrew L. Allen M. Anne Katzenberg Mikhail V. Sablin 《Journal of Anthropological Archaeology》2011,30(2):174-189
Interpretations of dog burials made by ancient foraging groups have tended to be based upon our own relationships with such animals and modern western cosmological and ontological concepts. Osteological studies of early dogs often focus only on issues of taxonomy, and as a result very little is known about these animals’ life histories. Eastern Siberia has produced many Holocene dog burials, but these are typically not well described and the explanatory frameworks provided for them are very underdeveloped. Here we examine in detail two Cis-Baikal canid burials, one of a wolf and the other a dog, both in large Middle Holocene hunter-gatherer cemeteries. We link the mortuary treatment of these animals to other cultural practices, particularly the treatment of the human dead, and broader patterns in Northern human-animal relationships. This interpretive model is combined with detailed osteobiographies for the canids and contextual information for these and other dogs and wolves from Middle Holocene Cis-Baikal. It is argued that canids here were understood and treated in a variety of ways. We suggest that some animals with unique histories were known as distinct persons with ‘souls’ and because of this at death required mortuary rites similar to those of their human counterparts. 相似文献
87.
G. W. Wood F.I.C. 《Folklore》2013,124(3):229-274
PALE HECATE'S TEAM. By K. M. BRIGGS. London, Routledge and Kegan Paul, 1962. Pp. 291 + 8 plates. 40s. net. Reviewed by H. A. Beecham. THE DARK WORLD OF WITCHES. By ERIC MAPLE. London, Robert Hale Ltd., 1962. Pp. 192 + 21 plates. 21s. net. Reviewed by H. A. Beecham. ATLAS DER DEUTSCHEN VOLKSKUNDE. Neue Folge: 4th issue, part 1. Edited by M. ZENDER. Marburg, G. Elwert, 1966. Maps NF 37–48. Explanations Pp. 233, with 28 text ills. Reviewed by Ellen Ettlinger. FOLKTALES OF HUNGARY. Edited by LINDA DÉGH. Translated by JUDIT HÁLÁSZ. Routledge and Kegan Paul, 1965. Pp. xlvi, 381.35s. Reviewed by Jacqueline Simpson. DAREDEVILS OF SASSOUN. By LEON SURMELIAN. George Allen and Unwin, 1966. Pp. 251. 30s. net. Reviewed by E. O. James. JEFET SCHWILI ERZHÄLT. Hundertneunundsechzig jemenitische Volkscrzählungen aufgezeichnet in Israel 1957–1960. Edited by DOV NOY. Berlin, Walter de Gruyter, 1963. Supplement-Serie zu Fabula, Reihe A, Band 4. Pp. xii + 376. DM 58. — Reviewed by W. F. H. Nicolaisen. 相似文献
88.
Talley C Kushner HI Sterk CE 《Journal of the history of medicine and allied sciences》2004,59(3):329-374
Beginning in the early 1950s, a series of epidemiological, biochemical, pathological, and animal studies demonstrated a link between cigarette smoking and lung cancer. A number of reputable scientists challenged these findings, but for a variety of reasons, including the behavior of the tobacco industry, historians have assumed that these objections were insubstantial and disingenuous. Viewing these objections in scientific and medical perspective, however, suggests that there was a legitimate and reasonable scientific controversy over cigarette smoking and lung cancer in the 1950s and early 1960s. That controversy had important consequences. A new chronic disease epidemiology emerged, transforming the role and importance of epidemiology to medical research. This new epidemiology supplemented Koch's postulates, establishing a statistical method that allowed for linking environmental factors to the etiology of chronic diseases. The 1964 report to the surgeon general, Smoking and Health, represented the denouement and codification of these developments. This reexamination of the scientific controversy over smoking in the 1950s and early 1960s provides an important context for understanding the subsequent public relations battles between the tobacco industry and public health after 1964. 相似文献
89.
90.
J. Buxeda I Garrigs R. E. Jones V. Kilikoglou S. T. Levi Y. Maniatis J. Mitchell L. Vagnetti K. A. Wardle S. Andreou 《Archaeometry》2003,45(2):263-284
The study of technology transfer in pottery production to the periphery of the Mycenaean world has been addressed by considering two different areas, southern Italy and central Macedonia. Technological features such as ceramic paste, decoration and firing have been determined for different ceramic groups established according to provenance criteria. The studies of technology and provenance have been performed following an archaeometric approach, using neutron activation analysis, petrographic analysis, X‐ray diffraction and scanning electron microscopy. The results have revealed the existence of two different models. On the one hand, southern Italy seems to exhibit a more organized pottery production, which follows a Mycenaean‐like technology, while in central Macedonia production is probably more varied, being based in part on the technology of the local tradition. 相似文献