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This paper provides the first systematic assessment of blanket mire degradation in the east Cheviot Hills, Northumberland. The extent of erosion is mapped over a 32 km2 area of peat. Erosion affects 37% of the blanket peat. Erosion forms consist of anastomosing (7%), linear (21%) and dendritic (9%) gully systems together with peat slides (<1%). Topography is the primary influence on gully system pattern. Spatial variations in gully form can be partly explained by position in the stream network (stream order) and local variations in the depth of peat. A sequential scheme of gully development is described. Gullies evolve initially through a phase of rapid downcutting to the peat base, followed by lateral erosion and gully widening becoming dominant through a process of roughly parallel wall retreat. As gully width increases re‐deposition of peat occurs and re‐vegetation occurs on the gully floor. Comparative photography reveals that gully patterns have been stable over the past 32 years and in some areas for over 70 years. It is possible that gully systems in places are in excess of 500 years old. 相似文献
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Christopher E. Baldwin 《Perspectives on Political Science》2013,42(2):67-74
Abstract Herbert Storing has persuasively argued that American political thought and statesmanship breaks with the tradition of classical political philosophy and statesmanship, particularly its concern with shaping the character of citizens and leaders, and instead sides with modern political philosophy, which has tended to encourage statesmen to forgo shaping the character of citizens and leaders and to focus instead on shaping institutions that will function regardless of citizens' virtue (or lack of virtue). An exception to this general rule, however, is Benjamin Franklin. Franklin, in the tradition of classical statesmanship, sought to shape not only American political institutions, but also and especially the character and way of life of his fellow citizens. Yet the character and way of life that Franklin helped lead his fellow citizens to embrace is uniquely modern and American in spirit. Thus, Franklin can be said to offer us an example of classical, but uniquely modern and American, statesmanship. 相似文献
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James A. Baldwin 《Journal of Cultural Geography》2013,30(1):17-27
The dingo, a distinct variety of dog, is generally considered to have been the only domestic animal present in Australia when Captain James Cook explored that continent's eastern coast in 1770. Nevertheless, there is evidence to suggest that a variety of pig was introduced to Australia from neighboring New Guinea, perhaps at a time prior to Cook's visit, and that a feral pig population existed on Queensland's Cape York Peninsula. Such evidence includes the carrying of pigs in the traditional Torres Strait trading system, the depiction of pigs in the Aboriginal rock art of the Cape York Peninsula, the presence of a typically New Guinea parasite in the Cape York feral pig population, the fact that these Cape York pigs are today quite similar in physical size and appearance to the pigs of New Guinea, the presence of prominent longitudinal stripes on newly-born piglets in both northeastern Australia and New Guinea, and finally the existence of a New Guinea-Torres Strait word for pig in the language of Aborigines living at Princess Charlotte Bay on the Cape York Peninsula. 相似文献
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Oral historians have begun to use interviews in significantways to supplement what may be described as the more traditionalinstitutional "bricks and mortar" histories of colleges anduniversities. Many large public universities in the Americaswere founded after 1850 and first published their historiesat the half-century mark following the beginning of the twentiethcentury. In many instances, these college histories focusedon firsts and founders and gave particular attention to thephysical development of the campus and especially the constructionof buildings. These two books, one from the University of Floridain Gainesville, and the other from the University of Albertain Edmonton, Alberta, Canada, present an interesting contrastin the use of oral history in tracing the histories of thesetwo universities from 1906 to 2006. In the 相似文献
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Jeff T. Williams 《International Journal of Osteoarchaeology》1992,2(2):131-138
Several errors in the early literature discussing life-table analysis of skeletal populations are potentially misleading to the researcher unacquainted with the mathematical methods of palaeodemography. Additional errors document the hazards of borrowing life-table methods and equations from other applications without fully realizing their context, interpretation, and the potential restrictions on their use. A simple generalization of the life-table equations explicitly to reveal their dependence on the entry age and width of the age intervals used will facilitate the correct computation of life tables and readily accommodate the use of unconventional or otherwise non-standard cohorts. A general procedure for computing a life table for a skeletal population is presented, and a numerical example is included to illustrate the method. 相似文献
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