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21.
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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Beatriz Caballero Rodríguez 《History of European Ideas》2018,44(7):887-898
ABSTRACTMaría Zambrano's biggest contribution to intellectual history is, without a doubt, her poetic reason; her unique attempt to overcome the limiting coordinates of the framework of rationality established by the Enlightenment. Having spent forty-five years in exile, the relevance of this Republican thinker has only been acknowledged in recent decades. Since then, the political content of her early work, as well as her engagement with the Republic's cause prior to and during the Spanish Civil War are well known. Nevertheless, although Zambrano still wrote some political books after the Civil War, most notably, Persona y democracia (1958), the political component of her thought after this period has passed largely unnoticed. This article intends to take a wider approach to Zambrano's political engagement by exploring the political significance of her poetic reason. Here I contend, first, that poetic reason, far from being an isolated attempt at developing an alternative rationality, is actually in line with the critique of instrumental reason proposed by the Frankfurt School and, second, that, in fact, there are meaningful parallels between poetic reason and Frankfurtian Critical Theory. Thus, the purpose of this article is to explore such parallels and their significance in revealing the political dimension of Zambrano's thought. 相似文献
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Rafael M. Martínez Sánchez Juan Carlos Vera Rodríguez Leonor Peña-Chocarro Youssef Bokbot Guillem Pérez Jordà Salvador Pardo-Gordó 《African Archaeological Review》2018,35(3):417-442
The period comprising the end of the Early Neolithic and the Middle Neolithic, dated broadly within the fifth millennium cal BC, corresponds to an interval that remains largely unknown in the extreme north-western tip of Africa. This situation contrasts with that of the Early Neolithic, a period characterised by the earliest evidence of the diffusion of a productive economy, cultivated plants and domestic animals. The paucity of data for these later phases can be explained in part by the lack of secure contexts and sequences based on radiocarbon datings of short-lived samples. The current study presents the results of the excavations of El-Khil Caves B and C that yield materials allowing re-evaluation of the chronology of a type of ceramic known as Ashakar ware. The study also identifies two traditions in the northern Moroccan Middle Neolithic. The first is heir to the so-called Impressa Mediterranean ware and rooted in the Cardial Neolithic, while the second is characterised by roulette cord impressions, red slip and tunnel lugs and probably rooted in the region of the Sahara, and has no technological precedents in the study area. 相似文献
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Diane Lyons Jeffrey Ferguson Diana Harlow Joanna Casey 《African Archaeological Review》2018,35(4):567-595
The study presents the results of neutron activation analysis (NAA) of contemporary pottery from Tigray Regional State, northern highland Ethiopia. This is the first regional-scale study of ceramic composition of Tigray’s pottery and is part of an ethnoarchaeological study of the material and social contexts of pottery production and consumption in Tigray’s Eastern (Misraqawi), Central (Mehakelegnaw), and North-western (Semien Mi’irabawi) zones. The analysis identifies clear compositional groups with strong regional patterns, an encouraging result for the use of NAA to study Tigray’s ancient pottery trade. Significantly, the study further contributes to discussions of how mutually constituted social identities of potters and consumers affect compositional patterning in the distribution of pottery in market networks. 相似文献
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This study takes a valuation perspective to study how and where products and innovations are gaining ‘economic significance’ in the contemporary economy. Building on a recent research stream in economic geography and urban and regional studies, it highlights that the economic value of many products is not formed within production systems alone, but relies on co-constructed connections between production and consumption systems, playing out across multiple geographies. It distinguishes between three types of economic valuation pathways – namely technical, experiential and identity-based – which although analytically distinct may actually build and reinforce one another. This approach is empirically illustrated with the case of the surf-related economy in the city of San Sebastian (Basque Country, Spain), which is used to make a broader point about the growing relevance of a valuation approach to understand competitive advantage and economic renewal in localized production systems. 相似文献