随着互联网时代的来临,网络数据已越来越成为表征居民地理行为的重要载体,用户迁移、社交网络、移动通信等地理行为大数据成为城市联系研究的重要数据来源。"百度迁徙"大数据通过LBS技术,全程、动态、即时和直观地记录了城市之间的人口日常流动轨迹。通过采集"百度迁徙"数据库中2015年一季度(2月7日至5月16日)国内369个城市之间的逐日的人口流动数据,分"季度平均、春运期间(春节前)、春运期间(春节后)、劳动节、周末和工作日"6个时间段,从人流集散层级、人流集散网络体系的分层集聚、人口日常流动空间格局及其与"胡焕庸线"之间的关系等角度分析各时间段的城市之间的人口日常流动相关特征与空间格局。研究发现,"百度迁徙"大数据清晰地显示了春运期间中部和沿海地区之间的人口流动格局。人流集散中心主要分布在京津冀、长三角、珠三角和成渝4大城市群中,并与其城市等级有较强的一致性。人口日常流动集散体系呈明显的分层集聚,京津冀、长三角、珠三角、成渝和乌鲁木齐5大集散体系在各时间段基本得到体现,而华中、东北、西南和福建沿海等地区并未出现高层级集散城市和高等级集散体系,与这些区域在国家区域发展战略中的地位在一定程度上不相匹配。"胡焕庸线"能较好地反映国家层面的城市之间人口日常流动格局,反映了地理环境对城市间人口日常流动的深刻影响。城市之间的人口流动强度是体现区域经济联系强度、城市等级和网络结构等的重要指标,此项研究可为形成国家区域经济发展新格局和促进区域平衡发展提供参考。
With the advent of the Internet era, network data has become an important carrier characterizing residents' geography behavior. The residents' migration, social network, mobile communications and other geographic behavior big data have become an important data source for urban interactive relationship research. "Baidu Migration" big data can fully, dynamically,immediately and visually record population migration trajectory with LBS technology. Through collecting population daily flow among 369 cities in China during the period from February 7to May 16 in 2015 in "Baidu Migration" and extracting six periods with "Quarter average,Spring Festival Transportation(before Festival), Spring Festival Transportation(after Festival),Labor Day, weekends, workdays", this paper tries to analyze and compare the characteristics and spatial patterns of daily flow among cities from the aspects of "population daily flow distribution levels, flow distribution layers network aggregation, spatial patterns and its relationship with the 'Hu Huanyong Line' for population flow". This paper analyzes the characteristics and spatial pattern of population daily flow among cities in each period. The result shows that "Baidu migration" big data clearly shows the pattern of population flow between the central and coastal areas in China during the period of Spring Festival Transportation. Main flow assembling centers are distributed in the urban agglomerations of Beijing- Tianjin- Hebei, Yangtze River Delta, Pearl River Delta and Chengdu- Chongqing, and those centers have strong coherence with those urban hierarchies in each period. Clear hierarchical structure and level distinction can be identified in the Yangtze River Delta, Pearl River Delta, Beijing- Tianjin- Hebei, Chengdu- Chongqing and Urumqi assembling systems in each period. But Central China, Northeast China, Southwest China and coastal Fujian do not present a pattern of higher level of urban assembling centers and high hierarchical assembling system