Flood Vulnerability Assessment of Immovable Cultural Heritage in Beijing's Ecological Conservation Area Across Climate Scenarios

Climate change is increasing the frequency of extreme precipitation events, making flooding a major natural threat to immovable cultural heritage. Focusing on seven study districts associated with Beijing's Ecological Conservation Area, this study developed a flood vulnerability assessment framework based on the Vulnerability Scoping Diagram (VSD), incorporating exposure, sensitivity, and adaptive capacity. GIS-based spatial analysis was integrated with flood-prone-area data derived from the Soil Conservation Service Curve Number (SCS-CN) method to calculate the relative flood vulnerability index (R) for 1969 georeferenced heritage assessment points under a baseline and three future Shared Socioeconomic Pathway scenarios: SSP1-1.9, SSP2-4.5, and SSP5-8.5. Mean R was 0.101 under the baseline and increased to 0.123, 0.126, and 0.120 under the three future scenarios, respectively. The number of points with high or very high vulnerability increased from 192 to 271–294. Higher R values were concentrated mainly in mountainous and riverine areas, with relatively high district-level means in Pinggu, Yanqing, Huairou, and Miyun. City- and county-level protected heritage had the highest mean R values under the future scenarios, whereas the large number of undesignated heritage points resulted in substantial cumulative management pressure. All 57 heritage points damaged by flooding in July 2025 were located in these four districts. The Gubeikou Town Wall Site and Shangying Castle Site showed large increases in R and also sustained flood damage, providing retrospective spatial-consistency evidence for the assessment. The framework provides a practical approach for regional flood vulnerability screening and conservation prioritization of immovable cultural heritage.