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This article constructs a conceptual and normative framework for policy-oriented discussions of environmental uncertainty and risk. Human-caused environmental risks are unavoidable in a technologically and economically advanced society. Contemporary environmentalists deploy ecological and ethical axioms to structure the debate over environmental uncertainty and risk management. They adopt the "imperative of sustainability" and the "precautionary principle" as the foci of an ethical and ecological effort to evaluate and limit environmental risk. The policy implications of these axioms for those engaged in environmental risk and cost/benefit analysis are explored.  相似文献   
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Abstract

ZOOARCHAEOLOGICAL ANALYSIS OF a substantial assemblage of animal bones excavated from Dudley Castle, West Midlands, suggests that a significant change in pig management occurred during the 14th century. A dramatic decrease in the relative abundance of pigs, combined with an increase in the size of post-cranial bones and teeth, and a higher proportion of neonatal individuals, raises the possibility that greater control over breeding and feeding was being exerted in this period through the emergence of enclosed husbandry practices. Carbon and nitrogen stable-isotope analysis of a sample of 41 pig mandibles from two tightly dated phases of occupation supports this interpretation. Between the late 13th century and later 14th century there was a statistically significant decrease in δ15N, but not in δ13C, and pig dietary diversity probably also decreased. This paper discusses several explanations for these patterns, all consistent with a major change in pig management at this time.  相似文献   
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The article briefly considers the question of conservation and oil displacement in recent years. It then focuses on the problem of petroleum supplies, on the factors affecting their expansion, and on Soviet efforts and plans in the field. Investment growth in the oil industry and its regional allocation in the 1980s and beyond are examined. The nature and thrust of the exploratory effort, its relationship to the new reserve classifications, and to prospects for the Soviet oil industry are analyzed. Finally, the causes of the current rebound in output and Soviet plans for field development are assessed.  相似文献   
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