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71.
《Geoforum》2017
Motivated by theoretical arguments about ethnicity and economics and by historical research on urban black communities in the United States, this paper investigates the resilience of the early twentieth-century Black Metropolis. The study tests hypotheses about changes during the Great Depression (1930–1940) in the advantages of various cities as locations of black communities’ ethnic economies, analyzing Census data on blacks’ representation in occupations reflecting the Black Metropolis’s professional, entrepreneurial, and cultural media pursuits. There is mixed support for the hypothesis that the nationally dominant urban centers of New York, Chicago, and Philadelphia had the most resilient Black Metropolises, a finding that casts doubt on claims that black communities in such key places enjoyed exceptionally favorable locational advantages. Yet, the results support the hypothesis that northern cities were, overall, more resilient locations than southern cities, particularly for black professionals and entrepreneurs, affirming the argument that the urban North’s Black Metropolises were vital economic opportunity centers for these black communities’ upper- and middle-classes. 相似文献
72.
李壮伟 《广东海洋大学学报》2010,30(6)
分析汕尾电厂临时倾倒区2006年倾倒的疏浚泥对所在海域水质、沉积物、生物群落及生物质量等的影响。结果表明,在倾倒过程中,海水中悬浮物、石油类的含量增加,属第三类海水水质;倾倒活动改变了生物群落的水环境,使群落种数减少,多样性、均匀度和丰度降低。倾倒活动结束1个月后,除海水中悬浮物的含量仍属第三类海水水质外,其他污染物含量均符合第二类海水水质标准,底栖生物恢复较缓慢。疏浚泥倾倒对海区沉积物质量和海洋生物质量的影响较小。 相似文献
73.
R. Alan Walks 《Area》2010,42(1):7-24
Gated communities have been characterised as representing processes of 'forting up' and 'civic secession', in which their residents use gating as a strategy for withdrawing from political life and from taking collective responsibility for others. The assumption is that the residents of private gated communities should be less likely to participate in political life, and/or be more likely to support political parties on the right who advocate privatisation, reduced government expenditures and lower taxes. If the act of living in a gated community is associated with either greater support for parties and policies on the right of the political spectrum, or limited political participation, then the growth of such forms of privatised communities has potential implications for the future of urban politics and even for national political systems. However, despite surveys that have dealt with social attitudes 'behind the gates', insufficient attention has been paid to the politics of gated community residents. This paper fills this gap through a comparative analysis of electoral behaviour during the 2006 federal election at the level of the polling station. Electoral participation and partisanship in 27 gated communities in three Canadian metropolitan areas is compared against that of non-gated residents. Regression analysis is conducted in order to determine whether gated community residents differ from their non-gated counterparts in the way they vote and their levels of electoral turnout, after controlling for social composition. The potential implications of this research are then discussed. 相似文献
74.
Bue Nielsen 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):62-69
Nielsen, Bue: Employment and economic activities in the EC. Geografisk Tidsskrift 84: 62–69. Copenhagen January 1984. Regional disparities in unemployment and economic activities in the EC in the late 1970'es. Various concepts of unemployment are discussed. The performance of regions and countries using different concepts are illustrated. 相似文献
75.
We conducted a land change analysis to determine if the forest communities of presettlement and present contain areas that are analogous in composition, using surveys of the Holland Land Company (1797–1799) and U.S. Forest Service (1991–1993) from western New York. Gridded forest-type maps are produced from each survey using two models: a uniform model that assumes each data grid cell is occupied by a single forest type, and a mixture model in which grid cells are assumed to be occupied by multiple forest types in different proportions. The mixture model consistently detects a larger area of analogous communities in the two time periods at both global and local scales. 相似文献
76.
77.
A management proposal aims to partly remove a WWII military causeway at Palmyra Atoll to improve lagoon water circulation and alleviate sedimentation stress on the southeast backreef, an area of high coral cover and diversity. This action could result in a shift in sedimentation across reef sites. To provide management advice, we quantified the proximate environmental factors driving scleractinian coral cover and community patterns at Palmyra. The proportion of fine sedimentation was the optimal predictor of coral cover and changes in community structure, explaining 23.7% and 24.7% of the variation between sites, respectively. Scleractinian coral cover was negatively correlated with increases in fine sedimentation. Removing the causeway could negatively affect the Montipora corals that dominate the western reef terrace, as this genus was negatively correlated with levels of fine sedimentation. The tolerance limits of corals, and sediment re-distribution patterns, should be determined prior to complete removal of the causeway. 相似文献
78.
79.
西部乡村民族社区景区化的内涵及表征——以云南典型乡村民族社区为例 总被引:2,自引:0,他引:2
从旅游活动要素及其空间效应着眼,对"景区化"与"乡村民族社区景区化"的内涵进行了界定,把社区事象的景观化、经济功能的旅游化、组织管理的业缘化等视为"乡村民族社区景区化"的具体表征;认为乡村民族社区景区化的结果,必将导致乡村民族社区向旅游社区的演变,并对乡村民族旅游社区的内涵及其类型特征作了初步探讨,进而细分出名义在场型、从业参与型、景观资产型、混合平衡型4种类型。对云南曼听五寨、雨崩村、泸沽湖落水村和里格村进行实证研究的结果表明,除了曼听五寨属于名义在场型外,其余为从业参与型旅游社区。 相似文献
80.