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151.
ABSTRACT. Total cleared area in a von Thünen land-use model drives an atmosphere externality which depresses agricultural productivity uniformly throughout the region. Exogenous events that encourage clearance and use of a larger cultivated area (output price or population increase) exacerbate the externality. Imposition of a simple, corrective tax on land rents does not reverse these patterns but does mitigate the increase in the externality and leaves cultivators with higher incomes than they would obtain without the tax. We examine an optimal tax on land rents, designed to maximize the social value of land rents in the region, and an output tax. 相似文献
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Madagascar's culture is a unique fusion of elements drawn from the western, northern, and eastern shores of the Indian Ocean, and its past has fascinated many scholars, yet systematic archaeological research is relatively recent on the island. The oldest traces of visitors are from the first century AD. Coastal settlements, with clear evidence of ties to the western Indian Ocean trading network, were established in several places over the next millennium. Important environmental changes of both plant and animal communities are documented over this period, including the extinctions of almost all large animal species. Urban life in Madagascar began with the establishment of the entrepôt of Mahilaka on the northwest coast of the island in the twelfth century. At about the same time, communities with ties to the trade network were established around the island's coasts. From the fourteenth to the sixteenth century, social hierarchies developed in several regions of the island. During the succeeding two centuries, Madagascar saw the development of state polities. 相似文献
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This paper questions the history of runrig townships in the western Highlands and Islands of Scotland. It challenges assumptions still held about their archaism and draws attention to the fact that many townships in the region show signs of having once been enclosed. It argues that these systems of enclosure, together with evidence for a more diffused system of settlement, constitute the pre-runrig landscape and further argues that the shift into runrig did not begin until the closing years of the medieval period. 相似文献
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Robert L. Bettinger 《Journal of Archaeological Research》1993,1(1):43-66
Great Basin archaeologists spent the 1970s and most of the 1980s tearing down the Desert Culture hypothesis without presenting compelling means for dealing with the empirical variability that made it untenable. Recent research seeks to understand this variability by examining the effect of key variables in extreme environmental contexts, especially in wetlands and at high altitudes, and by developing and refining models of optimality that anticipate variability as the local expression of general evolutionary ecological principles. Research on intraregional and ethnic variability has lagged behind—the former because it is said to be costly, the latter because it is problematical in theory. 相似文献
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