长三角城市群中心城市与周边城市的城际出行特征研究

Inter-city Travel Characteristics between Central and Surrounding Cities in the Yangtze River Delta Urban Agglomerations

使用移动定位大数据,在长三角三省一市范围内识别上海、杭州、南京中心城区与其他城市的跨城通勤、一日往返、高频两地往返3类城际出行,分别计算紧密联系范围。使用互联网地图API接口,测算上海、杭州、南京中心城区的交通等时圈,与3类城际出行紧密联系范围进行对比。上海、杭州、南京中心城区的交通等时圈均出现"圈层+飞地"形态。高铁等快速交通体系已经改变了长三角城市之间的时空关系。3个城市的紧密通勤范围、紧密一日往返范围、紧密高频两地往返范围各有特征,部分紧密联系范围也出现明显的"圈层+飞地"形态。交通等时圈反映的上海、杭州、南京的交通支持能力相对接近,但3种城际高频出行的紧密联系范围差异明显。3种城际高频出行反映了不同的跨城功能联系。中心城市与周边城市之间的跨城功能联系紧密程度不以空间距离为依据,也不与交通等时圈一致。长三角城市群和都市圈的规划必须认识到上述差异,制定相应的规划策略。

Three types of inter-city travel,including inter-city commuting,one-day round trip and high-frequency round trip,have been identified by using mobile positioning big data.Through calculating travel density between the central urban areas of Shanghai,Hangzhou,Nanjing and other cities,this paper then separately delimits the scope of close-linked regions of three inter-city travel patterns in the Yangtze River Delta urban agglomerations.With the Internet map API interface,the traffic isochrones of Shanghai,Hangzhou,and Nanjing's central urban areas are calculated and compared with close-linked regions,all of which appear in the form of'continuous circle+discrete polygon'.High-speed rail and other rapid transit systems have changed the spatiotemporal relationship among cities in the Yangtze River Delta.Each of the close-linked regions of inter-city commuting,one-day round trip and high-frequency round trip of the three cities has their characteristics.Some close-linked regions also have a visible form of'continuous circle+discrete polygon'.The traffic support capabilities of Shanghai,Hangzhou and Nanjing,which reflected in the traffic isochrones,are relatively close.However,the close-linked regions of the three high-frequency inter-city travels are significantly different.Three types of highfrequency inter-city travel reflect various inter-city functional linkages.The planning of urban agglomerations and metropolitan areas in the Yangtze River Delta must recognize the above differences and formulate corresponding planning strategies.