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91.
A chronic feature of Caribbean agriculture is the extent to which potential arable land lies idle. Some of this region's densely populated islands have more than one-third of their farmland in such a condition. Yet their populations have relied increasingly upon imported food for sustenance. During the 1970s this paradoxical situation was exemplified by Grenada, where possibly as much as 45 per cent of its farmland lay abandoned and imported food accounted for one-third of the national import bill. This paper first surveys the underlying factors accounting for idle land in this nation and then outlines the programs pursued by the People's Revolutionary Government (PRG) to reduce waste of this basic resource and, thereby, to effect a more stable economy.
Dans la scène agraire caraibe on trouve constamment des terres dormantes qui pourraient ětre cultivées. Quelques les, des plus fortement peuplées de la région, ont plus du tiers de leurs terres ambles dans une telle condition. Toutefois, leurs habitants se fient de plus en plus sur la nourriture importée pour se soutenir. Cette situation paradoxale s'illustre par la Grenade, des années soixante-dix, où jusqu'a 45 pour-cent du terroir aurait été abandonné, en méme que la nourriture importée se payait du tiers du budget disponible pour défrayer toutes les importations requises dans ľle. Cette communication souligne ďabord les facteurs qui ont Créé cette situation en Grenade, et présente ensuite les grandes lignes des programmes adoptés, par le gouvernement révolutionnaire du peuple, pour couiger cette situation et pour diriger ľle vers une économie plus stable qu'au paravant.  相似文献   
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This paper describes some developments in the diffusion pattern of Hutterite colonies in North America. Today, there are more than 300 colonies distributed over the four western provinces of Canada and five states of the United States. The spatial behaviour of the three Hutterite clan-groups is compared, and responses by the sects to the repeal of the Alberta Communal Property Act in 1973 are assessed. Finally, changes in the rate of diffusion and the management of colony division are examined.
Cette communication décrit quelques développements dans la diffusion des colonies ďHutterites en Amérique du Nord. Aujourd'hui, il y a plus de 300 colonies dispersées dans les quatre provinces de ľoeust canadien et dans cinq états américains. Nous comparons le comportement spatial des trois groupes, ou clans, principaux ďHutterites et nous évaluons les réactions des sectes àľabrogation de la législation, de 1973, de la loi pourtant sur la possession en commun de propriétés Finalement. on examine le gérance de la division des colonies, et les changements dans leurs taux de diffusion.  相似文献   
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Nearshore water circulation and bar patterns at Coledale, New South Wales, were surveyed daily over thirty-six consecutive days, from 3 November to 8 December 1978, to identify sequences of changes that might occur in response to spring-to-spring tide cycles of fourteen days, changing barometric and wind conditions associated with the passage of anticyclonic weather systems across the coast, and day to day variation in the nearshore wave regime. During the survey the bar patterns tended to vary from transverse bars, through a composite arrangement incorporating longshore and transverse bars, to a longshore bar pattern as the tide changed from its spring to neap tide phase. However, this sequence was too brief to unequivocally establish variations in nearshore bar pattern that might be attributed to the fourteen day, spring-to-spring tide cycle. Nevertheless, morphologic changes occurring in response to wave regime fluctuation at Coledale were broadly in accord with studies from elsewhere by Dolan et al. (1979, 1982), and Clarke and Eliot (1982, 1983) in that bars and rips were systematically distributed along the beach. At Coledale, bars tended to relocate approximately 0.4 and 0.75 of the distance along the beach from its southern end. The preferred bar spacing closely matches hypothetical standing waves trapped between the headlands of the Coledale embayment. Temporally, the nearshore morphology is highly responsive to wave regime changes such that, as primary breaker heights decrease and remain below Hmax=1.0m, the bar pattern changes from longshore through mixed to transverse bar patterns within three to five days. On one occasion the bar pattern switched from a longshore to a transverse bar pattern within twenty-four hours.  相似文献   
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Streamline analyses of mean monthly resultant surface winds over Australia are presented. Mean confluences represent either cyclone trajectories, or modal fronts. These analyses suggest that Australia's annual airstream climate is of two regimes: that of September to March inclusive, and April to August inclusive. The winter half-year is exemplified by a continental airstream source in southern Australia which diverges over virtually the entire continent. It continues into September and October, although dominating only the southern third to half of Australia, and is absent from November to March. During the summer half-year a new pattern emerges, with three maritime air stream sources represented over the continent: first, air from the Southern Ocean penetrates the south coast reaching its furthest northward extension from December to March inclusive; a second source originating over the Pacific Ocean dominates eastern and northern Australia; and a monsoon source originating over the Indian Ocean which flows overland affecting northern Western Australia. Two modal confluences are noted, one over northwestern Australia from November-February separating monsoon flow from that emanating from the east, and another extending from the west central coast east-southeastward to the southeast coast from November-March separating Southern Ocean air from that originating over the Pacific Ocean.  相似文献   
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