Long-Term LST Trends for Bulawayo (2000–2024).

Rapid urbanization and land use change in African cities are intensifying the urban heat island effect, yet their specific human health consequences for vulnerable populations remain critically understudied. This research addresses this gap by investigating the nexus between land surface temperature (LST) rise and health risks for street traders in Bulawayo, Zimbabwe, a city experiencing significant urban expansion. We integrated multi-temporal Landsat and MODIS satellite data (1995–2022) with socio-economic surveys of 150 street traders to quantify thermal trends and their perceived health impacts. Our analysis reveals a significant 228% increase in built-up area, driving a pronounced warming trend, with summer LST reaching 43.4°C. This thermal amplification is strongly correlated with impervious surfaces and shows a clear inverse relationship with vegetation cover. Critically, survey data expose severe heat-related morbidity, with nearly all traders (98.7%) reporting symptoms like headaches and 63.3% experiencing fainting spells, with the highest burden concentrated in high-density and industrial zones. This study conclusively demonstrates that land use changes are directly translating into severe occupational health hazards for the informal workforce. The findings provide an urgent, evidence-based mandate for urban planners and public health officials to implement targeted interventions—such as strategic urban greening, provision of shade infrastructure, and heat early-warning systems—to safeguard vulnerable populations and build climate-resilient cities in the Global South.

非洲城市的快速城市化与土地利用转型正不断加剧城市热岛效应，然而此类变化对脆弱人群的具体健康影响仍严重缺乏深入研究。本研究针对这一研究空白，以正经历显著城市扩张的津巴布韦布拉瓦约市为研究区域，探究地表温度（Land Surface Temperature, LST）上升与街头商贩健康风险之间的关联机制。本研究整合了1995年至2022年的多时序Landsat与MODIS卫星数据，以及针对150名街头商贩的社会经济调查问卷，以量化热环境变化趋势及其感知健康影响。分析结果显示，研究区域建成区面积显著扩张228%，推动了显著的升温趋势，夏季地表温度可达43.4℃。这种热效应放大与不透水面覆盖度呈显著正相关，同时与植被覆盖度呈现明确的负相关关系。尤为关键的是，调查问卷数据揭示了严重的热相关发病情况：近98.7%的商贩报告出现头痛等症状，63.3%的商贩曾出现晕厥发作，且健康负担最重的区域集中在高密度城区与工业区。本研究最终证实，土地利用变化正直接导致非正规就业群体面临严重的职业健康危害。本研究结果为城市规划者与公共卫生官员提供了紧迫的实证依据，要求其落实针对性干预措施——例如系统性城市绿化、遮阳设施配置以及热预警系统——以保护脆弱人群，并在全球南方地区打造气候韧性城市。