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César DUCRUET 《中国地理科学(英文版)》2012,22(1):97-108
The growth of peripheral ports to dominant hubs has been well documented in North America and Europe,and has led to the elaboration of several theoretical models.However,although changes in containerization growth have been taking place in the South and East Asia in recent years,particularly in China,only a few studies have fo-cused on this region.The Pearl(Zhujiang) River Delta(PRD) has a typical port system with hub and peripheral ports,and provides an excellent case for studying the Peripheral Challenge.This paper introduces the theoretical evidence of the Hayuth model and analyzes the evolution of the container port system in the PRD with five phases:1) phase I:preconditions for change and phase II:initial container port development in the 1970s and early 1980s;2) phase III:diffusion,consolidation,and port concentration in the middle and late 1980s;3) phase IV:the load center in the 1990s;and(4) phase V:the Peripheral Challenge since the late 1990s.The results illustrate that the Shenzhen port presents mounting challenges to the Hong Kong port,descending from a transshipment hub of China to a regional load center of Southeast China.Furthermore,this paper explores five points that have led to the evolution of the port system in the PRD:1) competition in the regional port systems;2) different interested parties;3) shift of investment strategies of in-ternational terminal operators;4) integration of shipping networks and reorganization of carriers;and 5) cost-based competition. 相似文献
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Impacts of Weather Conditions Modified by Urban Expansion on Surface Ozone： Comparison between the Pearl River Delta and Yangtze River Delta Regions 总被引：11，自引：0，他引：11
In this paper, the online weather research and forecasting and chemistry (WRF-Chem) model
is used to explore the impacts of urban expansion on regional weather conditions and its implication
on surface ozone concentrations over the Pearl River Delta(PRD) and Yangtze River Delta(YRD) regions.
Two scenarios of urban maps are used in
the WRF-Chem to represent the early 1990s (pre-urbanization) and the current urban distribution in the
PRD and the YRD. Month-long simulation results using the above land-use scenarios for March 2001 show
that urbanization increases both the day- and night-time 2-m temperatures by about 0.6oC and
1.4oC, respectively. Daytime reduction in the wind speed by about 3.0 m s-1 is larger than
that for the nighttime (0.5 to 2 m s-1). The daytime increase in the PBL height (> 200 m) is
also larger than the nighttime (50--100 m). The meteorological conditions modified by urbanization
lead to detectable ozone-concentration changes in the PRD and the YRD. Urbanization increases the
nighttime surface-ozone concentrations by about 4.7%--8.5% and by about 2.9%--4.2% for the daytime.
In addition to modifying individual meteorological variables, urbanization also enhances the convergence
zones, especially in the PRD. More importantly, urbanization has different effects on the surface ozone
for the PRD and the YRD, presumably due to their urbanization characteristics and geographical locations.
Even though the PRD has a smaller increase in the surface temperature than the YRD, it has (a) weaker
surface wind speed, (b) smaller increase in PBL heights, and (c) stronger convergence zones. The latter
three factors outweighed the temperature increase and resulted in a larger ozone enhancement in the PRD
than the YRD. 相似文献
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基于SD模型下的流域水资源-社会经济系统时空协同分析——以渭河流域关中段为例 总被引：14，自引：4，他引：14
以渭河流域关中段为例,以SD方法分别建立PRD系统线性增长模型、反馈增长模型和调水耦合模型,并采用Venp le软件进行系统仿真,结果显示:基于政府规划目标的线性增长模型是社会经济高速发展模式,但区内水资源供给与需求之间的缺口会持续加大;反馈增长模型可根据流域内水资源承载力状况调整社会经济发展目标,但难以完成关中地区所承担的发展和带动使命;调水耦合模型引入了区外水资源,地区缺水状况得到明显改善,社会经济发展保持较高的增长速度,是解决关中地区PRD问题有效途径,而调水工程和社会经济之间的协同则是近期需要解决的关键问题。 相似文献
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