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Growing evidence of global climate change has led to global concerns over the vulnerability of agriculture to drought. Located in a semiarid environment, southern Alberta has suffered significant losses of agricultural productivity due to drought hazards in recent decades. Understanding the relationship between crop production and drought conditions is essential for coping with increasingly uncertain climate conditions. This study attempts to quantify the magnitude of crop production vulnerability to drought in southern Alberta. The standard precipitation index is used to measure drought stress in the region. The empirical results provide a detailed picture of the spatial variation in crop production vulnerability to varying drought conditions. Vulnerability maps from this study reveal that pockets in the study area may experience significant productivity loss given the existing level of adaptive capacity. While the irrigation districts have been associated with a lower level of vulnerability than dryland outside the irrigated region, uncertain water supply under varying climatic conditions coupled with increasing water allocation for non‐agricultural uses may increase the vulnerability in these districts.  相似文献   
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Tom Munnelly 《Folklore》2013,124(1):115-120
The Euahlayi Tribe: A Study of Aboriginal Life In Australia. By K. Langloh Parker, with an Introduction By Andrew Lang. London: Archibald Constable &; Co., Ld. 1905. By E. Sidney Hartland.

The Negritos of Zambales. By W. A. Reed. Ethnological Survey Publications, vol ii, Pt I. Manila, 1904. By W. Crooks.

Among the Indians of the Paraguayan Chaco : A Story of Missionary Work, in South America. Told by W. Barbrooke Grubb, and his Fellow-Workers in the Chaco Mission of the South American Missionary Society. Edited By Gertrude Wilson, B.Litt London: Charles Murray &; Co., 1904. By E. Sidney Hartland.

L'Origine Des Pouvoirs Magiques dans les Sociétés Australiennes. Par M. Mauss. Paris: Imprimerie Nationale, 1884. By E. Sidney Hartland.

Der Ursprung der Religion und Kunst. Von K. Th. Preuss. Globus, LXXXVI, LXXXVII. Sonderabdruck, pp. 54. By R. R. Marett.  相似文献   
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Tom Perreault 《对极》2013,45(5):1050-1069
Abstract: This paper examines processes of primitive accumulation and livelihood dispossession on the Bolivian Altiplano. Through empirical examination of the social and environmental effects of mining waste, the paper demonstrates that indigenous campesino community members are experiencing livelihood dispossession by way of three interrelated forms of accumulation: accumulation of toxic sediments on agricultural fields; accumulation of water and water rights by mining firms; and accumulation of territory by mining operations. In the case under examination, full proletarianization is not taking place, and processes of dispossession are not a “fix” for an overaccumulation crisis. The paper argues for greater attention to the contingent role of nature's materiality in processes of dispossession and accumulation.  相似文献   
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Abstract

Observation of cause–effect patterns of change in coastal environments provides insights into vulnerable areas and supports prediction and adaptation to flooding and erosion. Historic and periodic (6–8 year intervals) imagery from the Landsat archive is used to investigate transformations in the Atlantic coast of two Scottish islands over the period 1989–2011. Supervised classification of spectrally normalized images followed by change detection and spatial analysis reveals the patterns of change and the location of the most dynamic coastal areas. Quantitative measures of recent shifts and movement rates of relevant coastal lines, such as the lower limit of land-based vegetation, are assessed with the Digital Shoreline Analysis System. While very low rates are indicated for horizontal changes in the position of the lower limit of land-based vegetation (0.3?m?y?1), specific areas have been subjected to high rates of coastal progradation as well as erosion (e.g. 2.5?m?y?1 at Stilligarry). Information derived from satellite data supports the characterization of geomorphologically dynamic coasts at regional scales. With a rich and open access archive of imagery, a commitment to continuity, and compatibility with the Earth observation missions of other space programs, the Landsat mission offers useful and otherwise unavailable data for monitoring of coastal areas.  相似文献   
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