| 摘要: |
| 随着气候变化加剧以及城市热环境
问题日益突出，居民暴露于热环境的不平等现
象愈发显著，亟需从空间规划与适应性策略层
面加以应对。以成都市为研究对象，构建基于
地表温度的热舒适指数，采用同心环分析法展
示热舒适及其不平等性的城乡梯度结构，并探
讨热舒适不平等性与城市绿地特征的关联机
制。结果显示，热舒适指数呈现“中心低、
外围高”的空间分布特征，并且在环带单元
内呈现出不平等空间分布。部分外围区域的
热舒适不平等程度高于中心城区。在关联机
制方面，植被混合度、树冠高度及归一化植
被指数对缓解热舒适不平等具有显著的调节
作用。基于实证结果与成都市的空间特征，
本研究提出基于自然的解决方案，通过优化
绿地覆盖率、结构形态与空间配置，推动资
源的均衡分配与空间分区治理，系统提升城
市热适应能力与环境公平水平。本研究为气
候适应性规划设计提供了理论支持与实践
路径。 |
| 关键词: 热舒适 空间不平等 环境正义 城市绿地 城乡梯度 热适应策略 |
| DOI：10.13791/j.cnki.hsfwest.20250414005 |
| 分类号: |
| 基金项目:中央高校基本科研业务费（2682025CX123）；成都市哲学社会科学研究基地人与自然和谐共生的美丽城市建设研究中心2025年度一般项目（MLCS2025YB01） |
|
| Urban-rural gradient of thermal comfort inequality and its associations with green spaces:The case of Chengdu |
|
CHEN Jie,HE Bin,LIU Sheng,JIANG Yuxiao,YANG Linchuan
|
| Abstract: |
| With the intensification of climate change and the escalating urban thermal environment
crisis, residents' exposure to heat, thermal comfort, and their spatial inequality have become
increasingly prominent. Addressing thermal comfort inequality has become a critical issue for urban
spatial planning and climate adaptation strategies. This study investigates the spatial patterns of
thermal comfort and the underlying mechanisms of spatial inequality in relation to urban green space
characteristics, using the central urban area of Chengdu, China, as a case study. In this study, we
constructed an urban-rural gradient of thermal comfort inequality using the concentric ring method,
centered on Tianfu Square, and integrated three key dimensions (thermal comfort, population
distribution, and inequality) into a comprehensive analytical framework. Following the existing
literature, we measured thermal comfort using a land surface temperature-based thermal comfort
index, which assumes that higher LST values correlate with reduced comfort and increased heat
stress. In addition, based on high-resolution census grid data, a population-weighted approach was
employed to account for the interaction between thermal comfort and population distribution. The
Gini coefficient was used to evaluate the degree of inequality, capturing spatial disparities in thermal
comfort across different census grids. The results reveal a gradient structure in Chengdu’s urban heat
environment. First, thermal comfort shows a general upward trend along the urban-rural corridor.
Residents in peripheral areas tend to have higher thermal comfort than those in inner-city areas.
Notably, areas located around 7 km and 13 km from the city center, corresponding approximately to
the Third Ring Road and Outer Greenbelt (Fourth Ring Road), demonstrate localized peaks in thermal
comfort, suggesting the influence of both built environment intensity and ecological infrastructure.
Second, thermal comfort inequality does not follow a simple trend but presents a non-linear
distribution. Inner-city zones (1-4 km from the center) have relatively low inequality levels (Gini
coefficient < 0.4), whereas suburban transitional zones between 8-25 km exhibit markedly higher
inequality (Gini coefficient > 0.6), followed by a gradual decline in inequality beyond this range. This
observation suggests that the central areas may be more uniformly affected by the thermal
environment, whereas the urban-rural transition zones exhibit greater variability, which may be
attributed to differences in urban greening and socioeconomic development levels. To further
understand the relationship between green space and thermal comfort inequality, we introduced three
green space characteristics, including NDVI, canopy height, and vegetation diversity. A ridge
regression model was employed to address collinearity among explanatory variables and ensure the
robustness of the estimation. The model demonstrates strong explanatory power (adjusted R2 = 0.605),
and a significant relationship was observed between green spaces and thermal comfort inequality. The
results suggest that all three green space indicators are negatively associated with thermal comfort
inequality, with vegetation diversity exerting the most significant mitigating effect. This outcomeimplies that not only the amount but also the structure and composition of urban green spaces play critical roles in promoting thermal equity. Furthermore, areas
with higher land-use mix and population density tend to exhibit lower inequality, underscoring the importance of compact and multifunctional urban
development in mitigating thermal injustice. From the perspective of underlying mechanisms, the study reveals that urban green space characteristics,
particularly vegetation diversity, canopy height, and NDVI, play a significant role in mitigating spatial inequality in thermal comfort. We suggested three key
mechanisms: 1) climate regulation, whereby diverse vegetation types enhance evapotranspiration and shading, thereby reducing local heat stress; 2) spatial
coverage, as multilayered green infrastructure expands the spatial reach of cooling services and reduces concentrated exposure to high temperatures; 3) social
buffering, where equitably distributed green spaces are more likely to benefit vulnerable communities and enhance their capacity to cope with thermal risks.
These findings underscore the importance of integrating both ecological functionality and equity considerations in green space planning to improve urban
thermal resilience and promote environmental justice.Based on these findings, we proposed a three-tiered planning strategy to improve urban thermal equity: 1)
prioritizing targeted interventions in high-risk, high-inequality zones, especially within the transitional urban belt; 2) enhancing the diversity and structural
complexity of green spaces to maximize climate-regulating and distributive benefits; 3) promoting equitable spatial distribution of cooling resources,
particularly in areas inhabited by vulnerable populations. This study not only provides theoretical support for understanding the interaction between urban
thermal environment gradients but also offers practical insights for promoting environmental justice and sustainable urban development. |
| Key words: thermal comfort spatial inequality environmental justice urban green space urban–rural gradient thermal adaptation strategies |
