活动空间视角下的老年群体地铁出行时空特征——以昆明市为例

运用昆明市老年公交爱心卡和常规地铁刷卡数据，考虑老龄化不同程度的影响，剖析老年群体的地铁出行特征，并从活动空间的视角重点解析和对比低龄老年群体和高龄老年群体的地铁日常出行和活动模式。结果显示：1）同非老年群体相比，老年群体移动性更低，出行时刻集中于早高峰时段，活动范围相对集中于市中心。2）随年龄增长，老年群体的移动性进一步降低，活动空间收缩，但对公共交通的依赖性增强。相较于低龄老年群体（60~69岁），高龄老年群体（≥70岁）具有“出行频次高、活动空间范围小”的出行特征。3）低龄老年和高龄老年群体的活动空间分布存在明显分异，其中高龄老年群体的活动空间向居住密集区聚集，且出行在较大程度上受建成环境的制约。

Spatiotemporal Characteristics of Subway Travel by the Elderly Based on Activity Space: A Case Study of Kunming

With the aging of society, the travel activities of the elderly, as a vital part of resident travel, have become the focus of transportation management in most cities. The widespread application of big data has enabled travel behavior to be analyzed in more detail, with the results revealing actual travel patterns and helping to gain an in-depth understanding of the daily travel of residents. In studies on travel patterns, several methods can be used to analyze the daily activity patterns of the elderly by combining big data with the theory of activity space. However, studies on the internal disparity in the travel behavior of the elderly remain limited. Hence, we conducted a comparative analysis of the travel behavior of age groups within the elderly from the perspective of activity space based on the smart card data of the Kunming subway system. In the analysis, we first compared the basic travel behavior of the elderly and nonelderly. Based on the findings, we divided the elderly who took the subway into 60-69- and over-70-year-old groups. Second, we compared the travel behavior and activity spaces of these two groups using a statistical and spatial analysis approach. The results showed significant differences between the elderly and nonelderly groups, the 60-69-year-old group, and the over-70-year-old group. (1) We found spatiotemporal differences in travel behavior between the elderly and nonelderly. Compared to the nonelderly group, the elderly group was less mobile. Their single-subway travel duration and frequency were lower, and they traveled more during the early peak hours. Their activity range was relatively concentrated in the city center, and their travel purposes showed a stronger orientation toward leisure and medical needs. (2) With increasing age, the elderly were less mobile, and their dependence on public transport increased. In detail, the over-70-year-old group had a shorter travel duration as well as a smaller activity space, whereas their travel frequency and number of visited stations were higher than those of the primary age group. Compared with the 60-69-year-old group, the daily activity pattern of the elderly over 70 years old could be summarized as being within a smaller activity space and higher in frequency. (3) The distribution of activity spaces of the two elderly groups was similar to each other, both in areas along metro lines 1, 2, and 3, without line 6. It indicated that the daily activities of the elderly mainly occur in central urban areas with high population densities. Regarding differences, the activity spaces of those over 70 years old were more concentrated in the densely inhabited districts along metro line 3, whereas the activity spaces of the 60-69-year-old group spread to low-density areas in the south and east. These findings may imply that factors, such as the built environment, largely restrict the subway travel of older people. In other words, their daily activities rely on facilities and transit more heavily. In conclusion, our results reveal the subway travel behavior and daily activity patterns of different-aged elderly groups, which verify the feasibility of smart card data in activity space analysis. Additionally, our study provides ideas for urban planning and transportation management in the aging era to promote social space equity.