Analysis on accessibility of medical emergency in urban waterlogging scenarios: A case study of the

doi:10.3969/j.issn.1004-9479.2026.06.20240944

Abstract

Abstract:

To explore the changes in medical emergency accessibility during urban waterlogging events, this paper improves the Three-Step Floating Catchment Area (3SFCA) method by coupling medical emergency demand with urban road network nodes. This approach comprehensively considers the shortest travel time and the emergency demand in inaccessible areas, providing a more holistic analysis of medical emergency accessibility. Using the "7·20" heavy rainstorm and waterlogging disaster in Zhengzhou as a case study, the results reveal the following: ① Medical emergency accessibility within Zhengzhou's Fourth Ring Road shows significant spatial disparities, with high-accessibility points clustering around more remote healthcare facilities. The overall accessibility has decreased due to urban flooding, leading to a decline in spatial equity; ② There is a negative correlation between medical emergency accessibility and population distribution, with urban flooding exacerbating this mismatch. The central urban areas experience intense competition for medical resources, while the northeastern region shows a surplus of supply; ③ The number of accessible medical institutions in key commercial centers has decreased, and response times have lengthened. Specifically, the number of accessible medical institutions within a 6-minute threshold decreased by an average of 2.8 institutions, and response times increased by an average of 23 seconds. This research provides evidence for government and relevant departments in the construction of urban medical infrastructure and emergency medical services, supporting decision-making in response to flood disasters.

Key words: urban waterlogging, accessibility, demand units, shortest travel time, 3SFCA

摘要：

为了评估城市内涝环境下的医疗急救可达性，本文以综合考虑医疗急救需求与城市路网节点为需求单元，综合考虑最短时间出行成本与不可达区域急救需求，改进三步移动搜索法，进行城市内涝环境下医疗急救可达性分析。以郑州“7·20”特大暴雨内涝灾害为例，研究结果表明：①郑州四环内医疗急救可达性具有明显的空间差异，高可达性区域呈点状聚集于偏远医疗机构周边，受内涝影响整体可达性降低，空间均衡度下降；②医疗急救可达性与人口分布呈负相关，城市内涝进一步加剧了可达性供需失配现象，中心城区医疗资源竞争激烈，东北部区域供大于求；③重点商业中心POI的可达医疗机构数目下降、响应时间延长，在6分钟阈值下可达医疗机构数目平均减少2.8所，平均响应时间延长了23秒。本研究成果可为政府和相关部门在城市医疗基础设施建设和急救服务等方面提供科学依据，并支持面向内涝灾害做出更加合理的决策。

关键词: 城市内涝, 可达性, 需求单元, 最短出行时间, 三步移动搜索法

Yueying LI, Xuequan ZHANG, Zhen HUANG, Liming SUN. Analysis on accessibility of medical emergency in urban waterlogging scenarios: A case study of the "7·20" heavy rainstorm and waterlogging disaster in Zhengzhou[J]. World Regional Studies, 2026, 35(6): 180-191.

李悦颖, 张学全, 黄震, 孙黎明. 城市内涝情景下医疗急救可达性分析——以郑州“7·20”特大暴雨内涝灾害为例[J]. 世界地理研究, 2026, 35(6): 180-191.

Figures/Tables 6

Fig.1 Technical route of medical emergency accessibility analysis

Fig.2 Study area data visualization distribution

Fig.3 Distribution of emergency medical care access before and after waterlogging under different time thresholds

Tab. 1 Clustering results of spatial correlation between accessibility and population before and after waterlogging under different time thresholds

聚类结果	正常			内涝
聚类结果	6 min	8 min	10 min	6 min	8 min	10 min
P值	－0.134	－0.198	－0.03	－0.151	－0.211	－0.03
高-高	86	30	190	72	10	141
低-低	270	212	216	273	206	199
低-高	218	274	114	232	294	159
高-低	273	331	327	270	337	344
不显著	1021	1021	1021	1021	1021	1021

Fig.4 Distribution of spatial correlation between accessibility and population before and after flooding

Fig.5 Average response time and the number of accessible medical facilities for commercial centers

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