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Recent research demonstrates that spatial interaction models may also be made to function as location models by the addition of appropriate hypotheses about structural adjustment. An appealing feature of the approach is that dynamics are explicitly incorporated. In this paper, the attempt is made to recast a problem from classical economic-geographic theory—that of agricultural location—within a spatial interaction framework. It is shown that a wide variety of models is potentially available, and the properties of a range of these models are selectively explored. 相似文献
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Christina Warinner Nelly Robles Garcia Noreen Tuross 《Journal of archaeological science》2013,40(2):868-873
Oaxaca, Mexico has been inhabited by humans for over 10,000 years. From the time of earliest habitation, this environment provided a wide floral subsistence to its human inhabitants, notably documented at the cave site of Guila Naquitz. Light stable isotopes, primarily carbon and nitrogen, have been used in dietary and environmental reconstructions throughout Mexico and Central America. We report a large isotopic study of wild and market plants from Oaxaca that demonstrates 1) overlapping δ13C values of C4 plants, including maize, and plants that utilize the Crassulacean Acid Metabolism (CAM) pathway for biosynthesis, 2) the existence of a significant C4 grass biomass, 3) the lack of isotopic separation in the δ15N of legumes and non-leguminous plants and 4) the increase in the nitrogen isotopic composition of crop plants relative to wild plant averages. These four observations are potential complicating factors in interpretations involving the origins and spread of maize agriculture, the relative amount of maize in the diet and assessments of trophic level or meat contributions to the human diet. 相似文献
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Jennifer F. Brewer Natalie Springuel James Wilson Robin Alden Dana Morse Catherine Schmitt Chris Bartlett Teresa Johnson Carla Guenther Damian Brady 《对极》2017,49(2):273-293
Facing challenges to the civic purpose of higher education, some scholars and administrators turn to the rhetoric of engagement. Simultaneously, the political philosophy of cosmopolitanism has gained intellectual favor, advocating openness to the lived experiences of distant others. We articulate linkages between these two discourses in an extended case study, finding that a cosmopolitan ethos of engagement in a rural context can improve (1) understanding among people ordinarily separated by spatialized social‐ecological differences, (2) prospects for longer term environmental sustainability, and (3) the visionary potential of collaborative inquiry. Despite globalization of food systems and neoliberal shifts in fishery management, an annual fisheries forum facilitates coalitions that overcome dichotomies between technocratic and local knowledge, extending benefits to fishing communities, academia, and public policy. Iterative and loosely structured capacity building expands informally through affective processes of recognition and care, as decentralized leadership supports collective mobilization toward alternate futures. 相似文献
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