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<正>At 9:50 in the morning on Sep.13th,2014,the eleven of us in"the Interview team to Southwest Tibet"finally arrived at the Nyingchi Mainling Airport,the most difficult airport in China at which to land a plane,despite it being at Tibet's lowest altitude.Setting our feet on the land of the Yarlung Tsangpo River Valley,we thought of what it was like in the air as we traversed the alpine region,where the narrowest space was no further than 4  相似文献   
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This paper explores the impact of animal manure application on the δ15N values of a broad range of crops (cereals and pulses), under a range of manuring levels/regimes and at a series of locations extending from northwest Europe to the eastern Mediterranean. We included both agricultural field experiments and areas where ‘traditional’ farming is practised. Our aim is to ground-truth interpretation of δ15N values in archaeobotanical crop remains as evidence of past growing conditions and husbandry practices. The results confirm the potentially radical impact of manuring on δ15N values in cereals, depending on manuring level, but indicate only a slight effect on pulses, which can fix atmospheric nitrogen. The expected geographical trend towards greater δ15N with increasing climatic aridity is not apparent, probably because the growing conditions for crops are ‘buffered’ through crop management. Each of these observations has fundamental implications for archaeobotanical interpretation of δ15N values as evidence of land use practices and (together with analysis of bone collagen/tooth enamel in potential consumers) palaeodiet.  相似文献   
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Across much of the rural South in the late-nineteenth and early-twentieth centuries, crop-lien systems of agriculture devoted to plantation crops restricted the spatial and economic mobility of many black Southerners. Where crop-lien systems were infrequent, however, black Southerners had somewhat greater spatial and economic mobility, particularly in connection with the wage labor of the lumber industries. This article investigates the connections between perceptions of racial identity, spatial mobility, and labor in both the lumber industry and in non-plantation agriculture in St. Tammany Parish in southeastern Louisiana using census records, historical newspapers, and archival sources.  相似文献   
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