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991.
Spatial structure of central places in Jilin Central Urban Agglomeration,Jilin Province,China 总被引:1,自引:1,他引:0
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. 相似文献
992.
In traditional urban geography, city contact research is a classic study element in city research. In general, researchers use the traditional gravity model to characterize the contacts that exist between two cities. The traditional gravity model assumes ideal condi- tions, but these preconditions and their results often do not exist in realistic conditions. Thus, we used a modified gravity model to char- acterize the city contacts within a specific region. This model considers factors such as intercity complementarities, government inter- vention, and the diversity of the transportation infrastructure which is characterized as the transportation distance instead of the tradi- tional Euclidean distance. We applied this model to an empirical study of city contact in the Zhujiang (Pearl) River Delta (PRD) of China. The regression results indicated that the modified gravity model could measure city contact more accurately and comprehen- sively than the traditional gravity model, i.e., it yielded a higher adjusted R2 value (0.379) than the traditional gravity model result (0.259). Our study also suggests that, in addition to urban-regional and metropolitan development, the complementarities of the basic functions of cities at the administrative and market levels, as well as the corporeal and immaterial levels, play very significant roles in the characterization of city contact. Given the complexity of city contact, it will be necessary to consider more relevant influential fac- tors in the modified gravity model to characterize the features of city contact in the future. 相似文献
993.
正让静态的土地"流"起来,使沉睡的资源让"活"起来,这是农村土地制度变革的核心追求,努力拓展土地"流"与资源"活"的制度空间,是当下和今后一个相当长的历史时期需要做出的不懈努力。十八届三中全会指出,要赋予农民更多的财产权利,主要是指依法维护农民的三大基本权利,一是土地承包经营权,二是集体经济收益分配权,三是宅基地用益物权。根据物权法规定,完整的所有权包括占有、使用、收益和处分权。目前法律规定农民对承包地拥有占有、使用、收益权,而对宅基 相似文献
994.
正上海节地政策的主要做法和内容,一是三个强调,强调规划引领,强调权益保障,强调公益性责任;一个确保,确保有限的土地资源用于支持产业的发展,转变管理理念,坚持问题和需求导向。二是强化规划的引导,在两规合一的基础上向 相似文献
995.
正《全国资源型城市可持续发展规划》(以下简称《规划》)是我国第一次针对资源型城全市制定出台全国性、专门性的规划文件,充分显示了党中央、国务院对资源型城市可持续发展问题的高度重视。长期以来,资源型城市作为我国重要的能源资源战略保障基地,为全国经济社会发展做出了巨大贡献,同时在发展过程中也积累了诸多矛盾和问题。加快资源型城市经济发展方式转变,尽快建立《规划》出台对资源型城市可持续发展具有重要指导意义 相似文献
996.
997.
998.
正11月27日,青海省国土资源信息化领导小组邀请国土资源部、宁夏自治区国土资源厅、省政府电子政务办公室和厅机关相关部门专家,在西宁对《青海省国土资源"一张图"工程建设项目总体设计方案》(以下简称设计方案)进行了评审。评审会由省国土资源厅副厅长朱小川主持。厅办公室主任邱纪春介绍"一张图"项目基本情况;广州城市信息研究所有限公司汇报并演示《青海省国土资源"一张图"工程总体设计方案》。根据国土资源部、省委和省政府提出的任务目标和要求,厅党委于年初调整和完善了省国土资源信息化领导小组架 相似文献
999.
1000.
一、双城市农业循环经济发展现状
双城市以种植和畜牧业为主,是我国农业大县。为追求农业经济增长,大量使用农药、化肥,消耗大量水资源,使得经济发展与环境保护间矛盾日益突出。 相似文献