| 摘要: |
| 全球持续变暖加剧城市热岛效应，
导致极端天气事件频发、广发，多种复合灾
害易造成严重经济损失，危害公众健康。通
过建立HEVA评估体系分别对大连市高密度
城区热、涝风险进行评估，以街区为单元，
融合RS+GIS 的方法生成高精度LCZ 地图。
结合Copula 联合分布函数评估热涝复合风险
空间分异。结果表明：第一，大连市高热风
险集中于高密度建成区，呈带状分布，高涝
风险呈散点式分布；第二，热涝风险复合评
估结果显示，建成区热涝复合风险总体呈现
协同增强状态，集中于商业区、轻工业区及
医疗区域；第三，地表覆盖区基本呈现风险
抑制状态，风险协同增强区域则临近建成
区；第四，地表温度是热涝复合风险贡献度
最大的因素。提出了多尺度的针对性防治策
略，为城市小区域规划提供参考。 |
| 关键词: 热涝复合风险 高密度城市 Copula HEVA 优化策略 |
| DOI：10.13791/j.cnki.hsfwest.20250409003 |
| 分类号: |
| 基金项目:国家自然科学基金项目（52108044） |
|
| Study on spatial differentiation and strategy of compound heat-flood risk in high-densitycities based on local climate zone |
|
ZHANG Hongchi,GAO Jialu,REN Shizheng,BAI Jin,GUO Fei
|
| Abstract: |
| With global warming, extreme weather and climate events are becoming more frequent and
widespread. China is a sensitive region and an area of significant impact from global climate change,
experiencing a notable increase in both extreme heat and extreme precipitation events. This type of
compound heat-flood disaster is prone to high heat and humidity, which greatly affects socioeconomic
and public health. Whereas high-density urban areas alter the environmental characteristics
of the subsurface, leading to increased heat island effects and severe floods, they are more vulnerable
to compound heat-flood hazards. Therefore, effectively responding to the risk of compound heat-flood
disasters triggered by extreme weather events has become an urgent task to be solved in the process of
promoting the construction of healthy cities in China. Firstly, the HEVA risk assessment system was
selected for individual risk, and after data standardisation, the improved CRITIC method (Criteria
Importance Though Intercrieria Correlation) was used to assign weights, and the heat (flood) risk map
was obtained through the superposition of the heat (flood) risk values of first level indicators.
Secondly, LCZ maps were drawn using RS and GIS methods for land cover types and built types,
respectively. Thirdly, the Copula function was used to construct the compound heat-flood risk index,
and SHAP was used to analyse the contribution of the indicators of the compound heat-flood risk, and
to propose targeted compound risk prevention and control strategies at both macro- and
neighbourhood scales (based on the LCZ framework).The results show that: 1) The heat risk ranges
from 0.25 to 0.65, and the risk is distributed in a band, decreasing from the high-density built-up areas
of the city to the surrounding areas. The high risk is concentrated in the eastern part of Ganjingzi
District, Shahekou District, and the northern part of Xigang District, which have high-density
buildings and intensive crowd activities. The natural mountains have a lower heat risk and are
distributed in the western and southeastern parts of the study area. 2) The range of flood risk is 0.26 to
0.54, with high-risk values showing a scattered distribution, mainly in the northern part of Ganjingzi
District, which contains large areas of arable land with high vulnerability. The low-density built-up
area in the northern part of Ganjingzi District has low hazard, low exposure, and low vulnerability,
resulting in a low flood risk. 3) The built types in Dalian are mainly distributed in the form of a belt,
with LCZ 5 accounting for the largest area. The land cover types are mainly distributed in the west
and north-east, with LCZ A accounting for the most area and LCZ B accounting for the second most
area. 4) The results of the compound heat-flood risk assessment were categorized into five classes,
namely, extreme compound risk (>2.0), heavy compound risk (1.5–2.0), moderate compound risk (0.5
– 1.5), normal fluctuation range (-0.5 – 0.5), and risk-inhibited state (< -0.5). The synergistic
enhancement of the built-up compound heat-flood risk shows a banded distribution, in which theextreme and severe compound risk shows a polycentric aggregation. The compound heat-flood risk of the land cover type mainly shows a risk suppression
state. (5) According to the SHAP analysis, the factors contributing most to the built types of LCZs are LST, child population density and elderly population
density indicators, and the factors contributing most to the land cover types of LCZs are LST, road network density, arable land density, year of construction
and POI density indicators. Accordingly, policy recommendations are made for multi-scale compound heat-flood risk. Macroscale: for multi-hazard risks,
targeted strategies are proposed from three perspectives: prevention, occurrence, and long-term development. A dynamic urban compound heat-flood risk
assessment long-term and short-term, should be established in cities, and a coordinated urban heat and flood early warning system should be set up. For
ongoing disasters, planning should be unified according to local conditions and urban/rural integration. In the long-term development of disaster prevention and
control, a system of high-temperature and flood mitigation strategies should be formulated with a clear division of powers and responsibilities from the national
to the local governments. Urban planning should take into account the synergistic effects of climate-environment-city-transportation and formulate small-area
targeted composite disaster mitigation strategies. Neighbourhood scale: Compact (LCZ 1-2) optimizes the spatial form and installs vertical greenery (roof and
fa?ade) to reduce surface temperatures and reduce the rain island effect. Open (LCZ 4-5) uses reflective building materials to reduce surface temperature and
install permeable paving. Re-evaluate the role of blue-green space in the compound heat-flood risk, rationally plan the ability of surface cover types (LCZ A
and B) to reduce temperature and fix water, and screen flood- and drought-resistant tree species to build mixed forests. Set up ecological buffer zones to prevent
green spaces from being overdeveloped or occupied. |
| Key words: compound heat-flood risk high-density cities copula HEVA risk mitigation strategies |
