Stability of Spatial Structure of Urban Agglomeration in China Based on Central Place Theory

This paper brings forward the concept of stability of the spatial structure of urban agglomeration(UA)based on Central Place Theory by introducing centrality index and fractal theory.Before assessment,K=4 is selected as parameter to calculate centrality index and fractal dimension(K represents the quantitive relationship between city and the counties in Central Place Theory),and then found the number of nodes,the type of spatial structure,the spatial allocation of nodes with different hierarchy affecting the stability of spatial structure.According to spatial contact direction and the level of stability,UAs in China are classified into five types.Finally,it is posed as a further question that how to use hierarchical relation K=6 and K=7 in central place system to coordinate with the assessment of stability of soatial structure is brought forward.

Spatial Structure of Central Places in Jilin Central Urban Agglomeration, Jilin Province, China

Using the radius of gyration from fractal theory, this paper describes the calculation of fractal dimensions for the four tiers of central places in the Jilin Central Urban Agglomeration(JCUA), Jilin Province, China and the structural characteristics of each tier: 1) the 1st tier central place, Changchun Proper(not including Shuangyang District), provides the most service functions and has the most stable primate position; 2) the 2nd tier central places, Jilin Proper, Siping Proper, Liaoyuan Proper and Songyuan Proper have unclear statuses and do not provide certain functions; 3) the 3rd tier central places comprise 23 county-level cities, counties and urban districts(including Shuangyang District of Changchun), exhibiting a dense spatial structure that agrees with theory; 4) the 4th tier contains the largest number of central places(248 designated towns), but they are loosely distributed. In this study, a spatial image of the JCUA was created, based on vectorized data of the urban settlement distribution, which was then modified and abstracted to create a hexagonal network covering the JCUA. Compared to the traditional central place model, the modified spatial image conforms to the K = 3 principle. In reality, however, the growth of some 3rd tier central places should be increased with the cities being upgraded to the 2nd tier so as to overcome that tier′s functional deficiency. The loose distribution in the 4th tier should also be changed. This apparent anomaly can be explained by the fact that the classic hexagon model used to describe the way market areas layout does not exist in the real world. However, this should not be viewed as an obstacle to using central place theory. If its assumptions are properly applied, it can still assist research into the spatial structure of regions.

SOME EMPIRICAL EXAMPLES OF CENTRAL PLACE MODEL IN CHINA'S RURAL AND URBAN STUDIES

At the beginning of the 1980s, the Central Place Theory(CPT) was introduced into China from the West. The authors of this article are the initiators of applying this model to China's urban and regional planning as well as to the allocation of commercial activities. Since the commodity economy has been developing in China for thousands of years,most of the areas in eastern plains and inland basins of the country show the spatial structure of typical central places scene. During some six years, the authors participatd in a lot of rural, urban and regional planning projects in which the spatial phenomena and relevant internal mechanism proved this medel and its deformation. This paper gives only a few examples of the application of CPT in China. 1. The distribution of rural markets: the empirical study is based mainly on the situation in Shengfang Town and its vicinal area, 2. The spatial combination of urban Systems; problems about city allocation in North China are emphasized, 3. Commercial centres in city and the networks: a crucial study on commercial distribution of the metropolis Beijing is done by using the central place model.

An Overall Urban System: Integrating Central Place Theory and Urban Network Idea in the Greater Pearl River Delta of China

Following a half century of popularity, central place theory experienced 20 years of neglect when the new urban system theory of network modeling gained attention at the beginning of the 1990s. However, central place theory remains valid, and it seems there has been a reemergence with it. Using the Greater Pearl River Delta (Greater PRD) as an experimental study region, this paper intends to present an empirical study that validates central place theory and shows that it can be integrated into an overall regional urban system. The study uses the compound Central Place Importance (CPI) to evaluate whether there is a hierarchy among the urban centers within the study area. The results indicate the existence of a hierarchy. Furthermore, empirical observation finds distinct complementarity relationships, rank-size distributions, and co-operative actions between the different cities, thus substantiating the claim that central place theory can be incorporated into an overall regional urban system. Besides, the presence of the densely distributed modern infrastructure system also appears to constitute a dimension of the overall urban system. There need further theoretical and empirical studies in order to support this proposition.

Materializing the “Urban Region” Concept by Integrating Ecological Networks and Central Place Theory

This paper attempts to integrate urban development and ecological conservation by applying and syncretizing the “urban region” concept from landscape ecology and the “city-region” concept from socioeconomics. First, various concepts pertaining to regions are discussed and then, the integration of ecological conservation and urban development on a regional scale is introduced. Subsequently, the Greater Pearl River Delta, in China, is used as a case study area and landscape ecology’s “urban region” concept is applied to produce a landscape spatial arrangement framework for an urban region. This framework is achieved through the following steps: conceiving the study area as a region that consists of two urban regions, arranging ecological conservation landscapes by establishing a regional ecological network within the urban-region rings;and formulating an urban development strategy using central place theory. The resulting landscape spatial arrangement solution includes natural protection areas that cover half of the study area, several key strategic urbanizing locations, and suggestions for the strict protection of certain agricultural land-use areas. We believe that this framework facilitates a feasible exploration of land-use planning on a regional scale, although more in-depth studies are required to refine this approach.

Evolutionary model of the central place hierarchical system

Central place theory is one of the two theoretical cornerstones of geography, yet it cannot be connected with other spatial structure models, fails to provide definite time-space parameter conditions, lacks an evolutionary process model, and does not easily enable construction of a complete theoretical system of regional spatial structure. This paper gives an in-depth analysis of the process and mechanism for production and evolution of central places of different grades, and constructs an evolutionary model of the central place hierarchical system. The results of deduction, analysis and simulation show that production and evolution of the central place hierarchical system may be divided into five stages. These stages are the embryonic, formative, improvement, maturation, and advancement stages. Affected by spatial location and centricity, central places have obvious differences in scale and functional structures. There are great differences in the scale of same-grade central places. However, low-grade central places could have larger scales than high-grade central places, and the central places of a central location may form the agglomeration area of central places. Based on the hypothesis condition of an isotropic plain, the research shows that it is possible not only to form proportional functional structures of central places, but also to produce non-proportional scale structures of central places, and thus to complete the transformation from rationalistic deduction of spatial equilibrium mode to an explanation and demonstration of an unbalanced practical model.

Central Place Theory and Distribution of Post Offices in Cities

The feasibility of application of the Central Place Theory in the distribution of post offices in cities is analysed, the grade scale structure and space distribution structure Shijiazhauang of post offices in city are studied, the research results prove the actual value of the Central Place Theory, and the suggestion of adjustment in the space distribution Shijiazhuang of post offices in city is put forward.

Diverse foraging strategies of breeding Swinhoe's Storm-petrel in the productive marginal sea of the Northwest Pacific

Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to maximize energy gains and cope with the intensified challenges of parenting and self-maintenance.Such tradeoff may stem from the heterogeneity of food resources and the constraints of central place foraging.Nevertheless,abundant marine productivity could alleviate the energy limitation for seabirds,resulting in a consistent foraging approach.Here,we investigated the foraging strategy during the breeding season of a cryptic small-sized seabird,Swinhoe’s Storm-petrel(Hydrobates monorhis),in the Yellow Sea,a productive marginal sea of the Northwest Pacific.Using GPS tracking,we evaluated habitat preference,quantified the foraging strategy,and tested if environmental conditions and individual traits influence foraging trips.We found that Swinhoe’s Storm-petrels preferred nearshore areas with shallow water and engaged in primarily short foraging trips.Distinctive southeastward and southwestward strategies emerged when combining trip metrics,including foraging direction,duration,and maximum distance.The bathymetry,proximity to the coastline,and sea surface temperature differed in two foraging strategies.Foraging strategies exhibited flexibility between individuals,potentially explained by wing morphology,in which longer-winged birds are more likely to embark on longer-distance foraging trips.These findings highlight the impact of environmental factors and individual traits on seabirds’foraging decisions in productive marginal sea ecosystems.Our study also provides valuable insights into the foraging ecology of this Asian endemic storm-petrel.

基于人口自由迁移流动的基本公共服务均等化研究

基本公共服务均等化是实现全民共同富裕的前提,也是中国式现代化的基础目标之一。人口的自由迁徙不仅是中国式现代化中人全面发展的显著标志,也是实现中国式现代化基本公共服务均等化以及共同富裕的重要途径。基本公共服务与人口迁移流动的空间差异都具有阶层性特征。基本公共服务的空间差异主要表现为不同等级地域基本公共服务的区域性和阶层性差异。人口迁移流动对推动不同等级地域基本公共服务均等化具有直接和间接的双重作用。推动不同等级地域基本公共服务均等化,不仅要加快城市化进程,更要提高农村基本公共服务水平。要推进城乡融合发展,优化市场体制机制,畅通人口迁移流动渠道,促进人口自由迁移流动,使人口迁移流动在推动基本公共服务均等化过程中发挥更大作用。

由创作地与赋作中心地的离合论汉赋的颂讽怨娱功能

赋体颂讽功能多使用在赋家居于或趋近政治中心之际,而怨娱功能则多使用在偏离政治中心或打算偏离之际,两者皆可以由赋篇创作地及赋作中心地窥探一二。如果仔细梳理赋体流变的历史,也会发现汉代大赋、言志赋、行旅赋、抒情小赋的流变与汉赋创作地、赋作中心地以及赋体颂、讽、怨、娱功能有一定的关联。

都市圈新城区乡村医疗服务中心地网络结构及其影响因素研究——以武汉市新城区为例

医疗服务是维护居民健康的重要保障。基于修正引力模型和社会网络分析法,分析武汉市6个新城区乡村医疗服务中心地空间网络结构及其影响因素。研究表明:(1)新城区乡村医疗服务中心地呈现网络结构,多中心层级化共存。医疗服务网络密度整体上处于初级阶段,总体关联度偏低,且大部分联系限于各区内部,整体节点聚集度较低。医疗服务中心地的网络非均衡性明显,形成了不同尺度的空间嵌套格局。(2)医疗服务中心地可分为6个子群,并呈现由内到外的圈层结构。6个子群的空间关联网络由北向南形成层次分明的板块,而且呈现出小团体现象。特别需要指出的是,子群的划分表现出鲜明的邻近指向特征,地理邻近关系对医疗服务中心地关联强度的影响比较明显。(3)空间邻近性、农业产值、第二产业企业注册资本、人口数量、城镇化水平、道路密度和交通可达性对新城区乡村医疗服务中心地空间关联网络强度的提高具有显著影响,而第三产业企业的影响并不显著。

湘中稻草湾锑矿区矿体空间分布规律及深边部找矿预测

稻草湾锑矿区位于湘中锡矿山锑矿田的北部,是近年来新发现的隐伏锑矿床,通过钻孔和坑探工程控制,锑矿资源规模已达到中型,是近年老矿山边部找矿的重要突破。通过对该矿床矿体空间分布特征以及控矿条件进行分析预测找矿靶区。经研究表明,锡矿山矿田各矿床的矿体自特定的层位产出,具有方向性、成群性、等距性等特征;矿体呈层状、似层状产出于上泥盆统佘田桥组(D_(3)s^(2))硅化灰岩和层间破碎带中;矿体受构造控制明显,稻草湾背斜为矿体富集提供虚脱空间;矿体的成矿有利岩性组合为佘田桥组(D_(3)s^(2))灰岩+佘田桥组(D_(3)s^(3))钙质页岩(总屏蔽层)。

西部地区相对集中行政许可权改革的路径选择--基于西部X市的实地调研

行政审批制度改革是加快政府职能转变、深化行政体制改革的重要抓手。相对集中行政许可改革作为现阶段行政审批制度改革的主要方式,在实践中存在两种改革模式:“三集中三到位”和“一枚印章管审批”。通过对西部地区X市开展实地调研,从公众满意度和政府职能转变双重视角出发对比两种模式,进而探讨“一枚印章管审批”同西部地区经济社会发展状况的适配性。分析可得“一枚印章管审批”改革模式更适宜在西部地区推广,但需要谋划建立科学机制以实现高效审批和审管联动。

隧道中心水沟及现浇盖板施工技术研究

隧道中心水沟传统施工工艺一般采取分次浇筑,沟壁模板易上浮,沟壁烂根,沟底、沟壁结合部位渗水,盖板在预制场预制后运输至现场安装,占地面积大,阻碍交通,施工效率低,施工代价大。基于以上原因,依托彭水特长隧道中心水沟施工,积极探索新技术,提出沟底、沟壁利用底部设置斜坡接口的组合钢模一次施工,采用滑动底模在现场进行盖板现浇施工,每次施工长度15m,工序循环快,施工效率高,节省了大量的人力、物力,该技术可推广应用至诸多盖板沟槽施工。

中国城市群空间结构的稳定性分析

应用中心地理论,引入中心性指数和分形网络维数等方法以及GIS格网化技术,按照交通原则,即K=4作为参照系,采用2004年基础数据,对由160个地级市和700多个县级市构成的28个城市群及其空间结构的稳定性进行了定量测度。结果显示:①中心性指数越大的城市群,其空间结构稳定性越强;②中心性指数越大,与中心地结构相似性程度越高,空间稳定性越强;③网络维数越大,城市群空间结构稳定性越强;④点列数越长的城市群空间结构稳定性越强;⑤依据中心性指数大小,可将中国城市群划分为单核分割型、单核偏离型、单核集中型、双核平衡型和双核偏离型共5大类型;⑥根据半升梯形模糊隶属度函数模拟结果,将中国城市群空间结构稳定性划分为强稳定型、较强稳定型、中等稳定型、弱稳定型和不稳定型共5个等级;⑦根据不同等级的城市群个数,认为中国城市群空间结构的稳定性相对较差。本文最后提出了技术应用、参数选择等方面存在的问题以及未来研究的重点。

基于居民购物消费行为的上海城市商业空间结构研究

我国城市商业空间结构研究多局限于基于物质空间的中心地体系研究,本文以改革开放后市场经济转型及消费者因素日益重要的零售环境变化为出发点,从居民购物消费行为空间入手,考察目前上海市的商业空间结构特征。本研究基于问卷调查及实地观察所获得的第一手资料,通过经验行为主义方法,总结出上海居民购物消费行为的一般特征,发现上海居民购物出行的空间等级结构较为明显并呈现扁平化的趋势,这与商业中心地的空间结构及其变化是相对应的;此外,本文创新性地得出上海市不同收入地区购物消费行为空间的等级结构特征,并发现了其与戴维斯模型类似的空间特征以及不尽相同的形成原因。

新疆旅游中心地等级体系初构

根据新疆旅游业发展现状与存在的问题,阐明了确定新疆旅游中心地的必要性。以旅游中心地概念及克里斯泰勒中心地理论为基础,针对新疆旅游业发展中存在的"瓶颈"——交通问题,分析计算了通达性指数与网尼克指数两个指标,结合新疆各地区的旅游景点和酒店数目,确定了新疆旅游中心城市(中心地)。利用以上四个指标进行聚类分析,划分了新疆旅游中心区域,从而初步构建了新疆旅游中心地等级体系。运用增长极理论进一步提出了新疆旅游中心地等级体系的布局模式。

基于中心地理论对银川市服务功能的解析

以银川为案例城市,通过2596名商场顾客、46个房地产开发项目的购房对象、10123名建筑工人、528辆就餐汽车、858名中学生等不同领域的实际调研,对银川市城市中心职能的特征与成因进行了科学诊断;从理论层面上试图归纳影响银川区域发展空间结构的中心地系统变化的基本模式以及区域性中心城市服务功能的变化趋势;探讨了强化我国西部地区中心城市服务功能的主要途径。

明清时期太湖流域的中心地结构

太湖流域是长江三角洲的核心组成部分。研究表明,该地区虽然水网密布,水系发达,并有太湖等大小湖泊存在,但并不影响中心地结构在该区域的形成,其形成机理是地形平坦、水系呈规则的圩田塘埔系统,及高度发达的市场体系。该中心地结构的中心城市是苏州,而苏州位于太湖流域的几何中心;另一方面,不同等级中心地的间距之间存在着高度的对应性。据此,根据太湖流域中心地的形成过程,可以给出以下的中心地结构的形成路径:区域几何中心决定最高等级中心地的区位;区域面积决定一级中心地与二级中心地之间及二级中心地之间的距离;高等级中心地之间的间距决定以后,余下的不同等级中心地之间的距离即可同时决定。由此,太湖流域中心地结构的形成体现了典型的自上而下的中心地形成过程与类型。这一形成过程具有一般性,即对任何一个中心地而言,都有一个自低等级中心地向高等级中心地的转化、升级过程,但对整个区域而言,却是高等级中心地首先形成,然后才是以此为中心各级不同等级中心地的相继形成,最终形成完整的中心地等级体系。其研究结论丰富与完善了中心地学说。

区位选择与人文地理系统的分形优化——关于城市区位分形理论一般原理与方法的初步探讨

以城市区位论为主线，提出区位选择的分形思想和方法，旨在探讨人文地理系统空间优化的基本理论。指出区位选择和空间优化应该遵循三个基本原则：自相似原则、匹配原则和包容原则。