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91.
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C. F. W. Higham 《International Journal of Historical Archaeology》1998,2(3):235-260
The Early Historic Period in the Mun Valley occupies a critical three centuries, from A.D. 500 to A.D. 800, a period often known as that of Zhenla, a name derived from early Chinese accounts. This article first describes early findings of fieldwork designed to illuminate the prehistory of the upper Mun Valley, a period which covers approximately two millennia, with initial settlement now dated between 1500 and 1000 B.C. It then considers the nature of the transition to the complex polities of Zhenla. This involves a combination of archaeological and documentary evidence. Sources for the latter are rare for the Mun Valley, but by broadening the area considered, it is possible to integrate archaeological and historical sources in order to portray the intensifying social changes which characterize the Early Historic Period. It is suggested that most of the Mun Valley was occupied by Khmer speakers during the Iron Age, people responsible for the transition to increasingly centralized polities of the Early Historic Period. In the upper reaches of the Mun catchment, and in the Chi Valley to the north, the late prehistoric inhabitants spoke Mon. They had close affinities with the Dvaravati polities of Central Thailand. If confirmed, this hypothesis would indicate a series of local trends towards increasing social complexity which we can recognize in the early epigraphic record. 相似文献
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Ralph E. J. Boerner Michael N. DeMers John W. Simpson Francisco J. Artigas Alejandra Silva Leslie A. Berns 《Geographical analysis》1996,28(1):56-66
This study examined landcover change during 1940–1988 in two contiguous landscapes of approximately 12,400 hectares in central Ohio, USA: an inertial till plain area and a more dynamic moraine area. Agriculture dominated both landscapes throughout, however, the cover of natural vegetation and urban-suburban development increased over time on the moraine while natural vegetation decreased and agriculture increased on the till plain. Markov process models for landcover change were constructed for three 14–17-year time intervals and for the entire forty-eight-year study period. Probabilities of self-replacement for agricultural lands (0.91–0.97) were higher and those for forests (0.54–0.65) lower than those reported for other landscapes. Predictions of landcover percentages for fifty years in the future were made using Markov process models derived from actual cover changes in 1940–1957, 1971–1988, and 1940–1988. All three models produced similar predictions for the inertial till plain area. In contrast, the three models' predictions differed considerably for the moraine area. Only the 1971–1988 transition matrix was sensitive to increases in urbanization and reforestation which began on the moraine in the 1970s. These results indicate that reliance on lengthy study intervals and net rates of change can obscure spatial and temporal patterns of landcover change that are caused by natural and socioeconomic factors operating on shorter time scales. 相似文献
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The disappearance of man‐made borders and the need for increased international cooperation seem to prelude a removal of unnecessary obstacles between actors in different countries. This article is concerned with the relationship between political borders, economic development of border regions and networking of companies located there. It presents a ‘state of the art’ of research on border region development and trans‐border networking by companies. Based upon this research, the article concludes with a discussion on conditions that influence the emergence of new corporate networking in border regions, including effective policy action. 相似文献
98.
ADA W. PRINGLE 《Geographical Research》1996,34(1):58-80
The history of dredging is examined for Cleveland Bay, 1883–1988, as the port of Townsville developed. Between 1883 and 1964 only intermittent data exist on localities, depths and quantities dredged but later much more detailed records are available for analysis. Geomorphological problems emerged and are considered with particular reference to material forming the seabed, the sediment yield from the coastal catchments and its seasonally and annually irregular delivery to the coast by the rivers, and sediment movement within the bay in response to wind, wave and tidal processes. Analysis of aerial photographs, 1941–1988, has enabled some dredging effects to be studied, especially relating to localised land reclamation and more widespread probable effects on seagrass beds and mangroves. 相似文献
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Some 630 Roman silver coins excavated at Augusta Raurica (Switzerland) have been analysed by non-destructive X-ray fluorescence and X-ray diffraction. Furthermore, the density and the weight have been determined. The measured average density of plated and massive depletion-silvered coins is lower than the density calculated from the chemical composition, whereas massive coins display equal values for both of the densities. Based on experimental X-ray investigations of modern silver (tempering, acid treatment, production of corrosion layers), the nature of corrosion products on silver, their impact on surface analysis, and aspects of wearing-off by circulation are briefly discussed. 相似文献