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Steven M. Graves 《Urban geography》2013,34(6):889-890
Globalization is constituted not only through interurban networks of global city regions, but also by intraurban linkages within city regions. In this article, we use the Madrid city region as a case study to analyze the emergence of new “globalization arenas”—dense agglomeration nodes of knowledge-intensive business services (KIBSs)—on the outskirts of large metropolises (METs). We focus on two distinct types of centers. New employment centers (NECs) are produced by intrametropolitan suburbanization and realignment of preexisting small agglomerations. Historic administrative cities (HACs) are created by suprametropolitan scale processes remaking historically autonomous centers beyond the MET, which are only now being articulated in metropolitan transformation. We use statistical, cartographic, and econometric techniques to analyze proximity and economic base characteristics of NECs and HACs. As KIBSs continue to evolve in patterns of decentralized concentration, HACs are becoming more important KIBS nodes amidst complex landscapes of functional specialization and repositioning. 相似文献
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采用传统的方法编制地价指数及更新基准地价需要大量的地产交易资料,而我国大多数城镇地产交易市场尚未发育完善,存在收集资料困难,操作难度大等问题。文中在研究城市地块变化及其测度的基础上,通过分析地块变化指数和地价指数之间的相关性,建立了相关模型,从而测算出地价指数并更新基准地价。以土地市场发育不太完善的广西县级城市——桂平市为例进行了实证研究,并采用德尔菲法对结果的合理性进行了分析。结果显示,专家评价平均值为49.83,标准差为2.256 7,符合度为99.66%,说明基于地块变化的基准地价更新的方法是科学可行的。 相似文献
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Natural Resources Research - Recognition of reservoir quality is an important objective in reservoir characterization process. By definition, the quality of a reservoir is described by its... 相似文献
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地貌单元的空间格局对地表的物质、能量分配具有决定性影响。针对当今地貌学研究中尚未形成比较系统的从人眼直视的角度(即侧面)研究地貌单元的垂直格局特征的理论与方法,该文分析了侧面的地学含义;从地貌单元在垂直侧面的物质与能量分异角度提出了侧面地貌景观的概念,据此分析了侧面地貌景观的基本内涵并探讨了其主要研究内容;结合前述研究,分析了侧面地貌景观的尺度性、复杂性和系统性特征。在前期实验研究的基础上,初步提出了侧面地貌景观量化分析的基本思路与技术方案。研究工作对于人们进一步深化对地貌的科学认识具有一定的参考意义,但相关理论观点和方法有待进一步的实践检验。 相似文献
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Abstract According to recent research, one of the most promising strategies for intraurban job growth lies promoting localized clusters that produce goods and services which are primarily sold within a single city, metropolitan area, or urban region. However, in order to design urban policies to create or reinforce local clusters, the first challenge is to measure in a reliable way the clustering tendencies of different kinds of economic units in intraurban space. The aim is to compare the similarities and differences in results obtained from two methods designed to measure global clustering tendencies (the planar and network K-functions) in terms of characterization, scale, and intensity of intraurban localization patterns for tertiary economic units in a Latin American metropolis. It is concluded that the network K-function is a more appropriate method for measuring agglomeration patterns, scale, and intensity at the intra-urban level. 相似文献
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中国是单一制国家结构,行政管理采取隶属性质的层级式行政区划方式。美国是联邦制国家,各州采取相对独立的地方政府模式进行管理。中国行政区划单位和美国地方政府单位在内涵上有很大不同,我国现行行政区划名称的英译存在一些误解和误译,如果对此没有充分认识,容易导致翻译和跨文化交际失误。论文通过对中国行政区划单位和美国地方政府单位进行对比,旨在揭示它们之间存在的实质性差异以及名称上的可译性限度。 相似文献
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《湿地科学与管理》2001,(2):23
北京市：北京市平谷县人民政府果品办公室
天津市：天津市林业局营林处
河北省：河北省林业科学院
山西省：山西省林业技术推广站
内蒙古自治区：赤峰市林业科学研究所
辽宁省：辽宁省林业科学研究院
吉林省：吉林省林业科学研究院
黑龙江省：黑龙江省防护林研究所
上海市：上海市林业病虫防治检疫站
江苏省：江苏省林业科学研究院
浙江省：浙江省林业科学研究院
安徽省：安徽省林业外资项目办公室
福建省：福建省建瓯市林业技术推广中心
江西省：江西省萍乡市林业技术推广站
山东省：山东省林业技术推广站
河南省：河南省林业科学研究所
湖北省：湖北省林业科学研究院
湖南省：湖南省林业科学院
广东省：广东省林业科学研究院
广西自治区：广西林业科学研究院 相似文献
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Maliha S. Nash Walter G. Whitford David F. Bradford Susan E. Franson Anne C. Neale Daniel T. Heggem 《Journal of Arid Environments》2001,49(4):695
The objectives of this study were to determine if metrics for ant species assemblages can be used as indicators of rangeland condition, and to determine the influence of vegetation and ground cover variables, factors often influenced by livestock grazing, on ant communities. The study was conducted in two areas in the Great Basin: a sagebrush-steppe in southeastern Idaho (n=30 sites), and a salt-desert shrub in western Utah (n=27 sites). Sites were selected based on known rangeland condition (i.e. good, fair, poor) associated with livestock grazing. Ant communities differed considerably between the two study areas. Collectively, more ant species occurred at the Idaho sites (30) than at the Utah sites (21), relatively few species (eight) occurred in both areas, species richness was significantly greater at the Idaho sites (mean=12·0 species) than the Utah sites (mean=6·9 species), and Formica spp. were diverse (total of 15 species) at the Idaho sites but rare (one species) at the Utah sites. In Idaho, all species collectively, generalists, and Formica spp. were significantly less abundant on sites in poor condition than that on sites in good or fair condition, whereas in Utah, seed harvesters and Pheidole spp. were significantly more abundant on sites in poor condition than that on sites in good or fair condition. In Idaho, species richness was significantly lower on sites in poor condition. In Idaho, species richness and relative abundances of several ant groups were significantly related to bare patch size and parameters for cover or species richness of several vegetation groups. In contrast to the comparisons involving sites in poor condition, no differences in ant communities in either Idaho or Utah were evident between sites in good and fair condition. Thus, the ant communities responded only to large changes in rangeland condition and to large differences in climatic/edaphic conditions between the two areas. Hence, ant community metrics appear to have limited utility as indicators of rangeland condition in the Great Basin. 相似文献
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面向国土规划的空间评价标准地域单元划分 总被引：1，自引：0，他引：1
国土规划是宏观尺度国土空间开发、保护与治理的政策性依据。为了便于国土规划政策的实施,一般采取某一级别的行政单元进行分区,但现有静态性行政区划体系不利于国土空间政策一致性和差异性表达。根据欧盟国土空间规划关于标准地区统计单元划分(NUTS)的启示,提出了国土空间标准地域单元划分理念,构建了标准地域单元划分的原则、依据和技术路线,并以中国中部地区湖南省为例,对省级尺度国土空间标准地域划分的具体实施途径进行了探讨。研究结果表明,标准地域划分是国土规划关于国土空间综合分区进行空间评价的基础,能为国土规划编制提供更好的单元选择服务。 相似文献
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We used 210Pb-dated sediment cores from wetlands and Blue Cypress Lake, in the Upper St. Johns River Basin (USJRB), Florida, USA, to measure historical accumulation rates of bulk sediment, total carbon (C), total nitrogen (N), and total phosphorus (P). Marsh cores displayed similar stratigraphies with respect to physical properties and nutrient content. Wetland sediments typically contained > 900 mg organic matter (OM) g–1 dry mass, > 500 mg C g–1, and 30–40 mg N g–1. OM, C, and N concentrations were slightly lower in uppermost sediments of most cores, but displayed no strong stratigraphic trends. Total P concentrations were relatively low in bottommost deposits (0.01–0.11 mg g–1), but ranged from 0.38–2.67 mg g–1 in surface sediments. The mean sediment accretion rate in the marsh since ~ 1900, 0.33 ± 0.05 cm yr–1, was calculated from ten 210Pb-dated cores. All sites displayed increases in accumulation rates of bulk sediment, C, N, and P since the early part of the 20th century. These trends are attributed to recent hydrologic modifications in the basin combined with high nutrient loading from agricultural, residential, and urban sources. 相似文献
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Late Quaternary soils in southern New Mexico support previous work that suggested pedogenic gypsum accumulates in successive stages as a function of time, similar to pedogenic carbonate. However, gypsum also occurs as small (0·5–1 mm), powdery spheres that we term snowball morphology. The snowball morphology represents one of the initial stages of pedogenic gypsum development. Scanning electron microscope analyses indicate that soil microorganisms and organic material may play a crucial role in the development of this morphology. However, no trends were found in the crystal habits of gypsum suggesting the snowball morphology forms in a dynamic environment. 相似文献