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The influence of altered fire regimes on the denudation of a catchment is determined from alluvial deposits of the last 10,000 yrs and by monitoring runoff and erosion before and after a wildfire. An increase in fire frequency beginning at 3,000–4,000 yrs BP, as a result of intensified Aboriginal burning, did not change the mechanisms or rates of denudation nor did it cause widespread alluviation as suggested by others. The results of monitoring show that before and after mild fires there is insufficient runoff on most slopes to entrain sediment. Only after intense fires are runoff and erodibility increased enough to significantly accelerate erosion. Conditions are then identified which are most likely to lead to accelerated erosion from altered fire regimes in other catchments.  相似文献   
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The success of government efforts to stimulate energy conservation among the public ultimately depends on understanding patterns of energy consumption, perceptions of energy resources, and the adoption of conservation practices. These issues were addressed in a survey of residents of Edmonton and Calgary. Most respondents dismissed the seriousness of energy problems at the provincial level, although energy scarcity at the national and global scales was widely recognized. Conservation behaviour was characterized by a narrow range of adjustments perceived and adopted, attributable largely to patterns of resource perception and socio-economic factors.
La réussite des efforts gouvernementaux pour stimuler les conservations d'energie dépend, en dernière analyse, d' une compréhension des schémas de la consommation énergétique, desperceptions des resourcesénergétiques, et del'adoption d' habitudesconservatrices. On a interrogé les habitants d' Edmonton et de Calgary ace sujet. La plupart des réponses ignorent la gravité des problèmes d'énergie au niveau provincial, quoiqu'elles admettent la précarité des ressources énergétiques à l' échelle nationale et mondiale. L' attitude conservatrice se distingue plus particulikrèment à partir d' ajustements limités reliés géneralement aux schémas de perceptions énergétiques et aux facteurs socio-économiques.  相似文献   
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This article seeks to establish that the 1892 general election marked a major change in the relative positions of the parties in the Unionist alliance. Not only did it reveal the limitations of the Liberal Unionist Party's strategy and appeal in an age of increasingly organised, mass politics, but it also acted as a brake on the ambitions of the new leader of the Liberal Unionists in the house of commons, Joseph Chamberlain. It argues that the Liberal Unionist Party suffered a more severe setback in 1892 than has been recognized hitherto and that Chamberlain's attempts to revive his party both before and after the general election were now prescribed by the reality of the political position in which the party now found itself. Rather than regarding the fluid political circumstances of the 1890s as the outcome of an emerging struggle between increasingly polarised ideologies, it seeks to reinforce the significance of local political circumstances and the efficacy of party management in the growing dominance of Lord Salisbury and Arthur Balfour and the Conservative central organisers.  相似文献   
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