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101.
William J. Carlyle 《The Canadian geographer》2004,48(2):137-151
Specialty crops have risen from being of little to great importance in Saskatchewan agriculture over the past 20 years. Many interrelated factors have contributed to this change. These factors are analysed using a food supply system model that involves inputs, on-farm production variables, research and linkages to farmers, contracting, transportation and processing and market development for specialty crops. Specialty crops, especially the dominant trio of pulse crops, dry field pea, lentil and chickpea, reduce input costs, have proved to be agronomically suitable to fill much of the land made available through the decline of spring wheat and summerfallow in Saskatchewan, have benefited from research and its transfer to farmers and farmers' producer groups, are transported to local or regional processors and have benefited from the development of domestic and foreign markets. Specialty crops as a group tended to be relatively more important in 2001 in the Brown and Dark Brown than the Black and Grey soil zones, although each main specialty crop displayed a distinct geographical pattern. 相似文献
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Graham Harrison 《Development and change》2004,35(5):1037-1047
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William Reno 《Development and change》2002,33(5):837-858
The phenomenon of failed states might be expected to lead to the development of mass–based social movements to address the typically ensuing social problems. This article explores the general failure of reformist insurgencies to develop in failed states, using analyses of Nigeria’s Bakassi Boys and Oodua People’s Congress, and references to other armed groups. The cause of this failure is found in the legacy of patronage politics, especially the strategies of rulers who monopolized economic opportunities as a way of controlling people. As centralized patronage networks fragment, popular movements develop to challenge this control. Local political entrepreneurs, however, continue to dominate local markets, including clandestine ones, and use this social domination to buy off members of mass movements. As their new patrons give them access to weapons and protection against rivals, the organizational position of members who pursue individual economic interests is enhanced, while the people with more overt ideological agendas are marginalized. 相似文献
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On the Rank-Size Distribution for Human Settlements 总被引:9,自引:0,他引:9
William J. Reed 《Journal of regional science》2002,42(1):1-17
An explanation for the rank-size distribution for human settlements based on simple stochastic models of settlement formation and growth is presented. Not only does the analysis of the model explain the rank-size phenomenon in the upper tail, it also predicts a reverse rank-size phenomenon in the lower tail. Furthermore it yields a parametric form (the double Pareto-lognormal distribution) for the complete distribution of settlement sizes. Settlement-size data for four regions (two in Spain and two in the U.S.) are used as examples. For these regions the lower tail rank-size property is seen to hold and the double Pareto-lognormal distribution shown to provide an excellent fit, lending support to the model and to the explanation for the rank-size law. 相似文献
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