| The Great Wall relics are under the threat of various risks due to climate change.A typical case in point is the Great Wall cultural belt in Beijing,which is particularly vulnerable to the impact of changing climatic conditions.The Beijing section of the Great Wall is situated in the northern and northeastern mountainous areas,which experience rainstorm disaster during the summer season.This makes the Great Wall relic prone to damage by water erosion,flash floods,and intense rainstorm disaster.Investigating the effects of climate change on the Great Wall cultural belt in Beijing is crucial to effectively conserve the Great Wall relic.This study takes the 1894 Great Wall single buildings and fortresses in Beijing as the research object,and constructs a conceptual model for storm disaster risk assessment of the Great Wall cultural belt in Beijing based on disaster risk assessment theory using the index system method.The index system method is used to establish a three-dimensional storm disaster risk assessment index system,which includes the hazard of disaster-causing factors,the vulnerability of relics,and the sensitivity of disaster-inducing environments.The entropy weight method was employed to calculate the index weights,and the assessment results are visualized using Arc GIS software.To analyze the temporal dimension,I selected data from1980 to 2020 and used the CMIP6 model data and PLUS model to predict precipitation and land use changes from 2025 to 2050,constructing a time series to analyze trends.For the spatial scale,I obtained the spatial distribution map of each indicator through interpolation and reclassification using Python and Arc GIS based on the thin plate spline function.Using the factor detection and interaction detection modules of the Geo Detector,I analyzed the evolutionary attribution of storm hazards in the cultural zone of the Great Wall of Beijing for previous years.Finally,based on the existing preventive conservation model of architectural heritage,this study proposes a framework for storm hazard management strategy for the Great Wall cultural belt in Beijing.Specifically,this study draws the following conclusions:(1)Considering the heterogeneity of the Great Wall relic due to its types and materials,this study first selected six indicators reflecting the Great Wall relic’s own attributes and conservation value in terms of exposure,vulnerability and heritage value as the assessment indexes of heritage ontology vulnerability.According to the results of vulnerability assessment,most of the heritage sites are in very low vulnerability and low vulnerability,accounting for39.28% and 28.72%,respectively.A small number of heritage sites are of high and very high vulnerability,mainly located in Yanqing and Miyun districts.(2)For the hazard assessment of the causative factors,the daily precipitation data of 20 stations in Beijing from 1980 to 2020 were extracted and calculated by selecting the annual precipitation,the maximum daily precipitation,and the number of consecutive three-day precipitation events,and by comparing the simulated data of 20 CMIP6 models with the station observation data in the historical period(1980-2014),the simulated capability of each model was evaluated,and five models were selected.The precipitation data of the five models for the future period(2025-2050)were processed by the Delta downscaling method and the multimodel ensemble method to obtain the predicted future precipitation conditions and hazard indicators.and hazard indicators.Overall,there is a decreasing trend of annual precipitation in Beijing,but there is an increasing trend of daily precipitation and the number of three-day precipitation events,which means that the total precipitation in Beijing is decreasing and the short calendar rainfall is more frequent and concentrated.(3)The analysis of land use changes in Beijing over the years shows that forest land has been the main land use type in Beijing,and the area where the Great Wall relic is located is also mainly forest land.This study extracted the land expansion in different time periods and analyzed the degree of contribution of each driver to the land use change in Beijing based on the PLUS model.The results showed that the largest expansion of construction land was1808.68 km2 from 1990 to 2020,and,topography and temperature had the greatest influence on the expansion of each type of land.The land use demand in Beijing from 2025-2050 was predicted by the linear regression method and Markov chain method,and it was concluded that the proportion of construction land and forest land will increase year by year in the future,and on the contrary,the proportion of cultivated land and grassland will decrease year by year.(4)The results of the assessment of the risk of rainstorm disasters at different times show that,except for the very low-risk heritage sites,the rest of the heritage sites of each risk level have an increasing trend,which means that the risk of rainstorm disasters in the Great Wall cultural belt of Beijing may increase in the future due to the influence of climate change,and the medium and high-risk Great Wall relics are mainly located in Miyun,Pinggu and Yanqing districts.Among them,there are 16 Great Wall relics with higher risk levels in all years,most of which are fortresses,indicating that the larger the scale of heritage sites are more vulnerable to storm hazards.(5)According to the results of factor detection and interaction detection by Geo Detector,river network density and erosive precipitation days are the most important driving factors affecting the risk of rainstorm disasters in the Great Wall Cultural Belt of Beijing,while annual precipitation and land use also have significant effects on the risk of rainstorm disasters in the Great Wall Cultural Belt.The strongest interactions are the interaction between river network density and erosive precipitation days and the interaction between river network density and annual precipitation,i.e.,the greatest differences in risk indices are found for different erosive precipitation days with the same river network density.Overall,this study provides a framework for assessing the risk of stormwater hazards for large-scale linear cultural heritage(e.g.,canals,cultural routes of the Belt and Road),which can be used as a reference for decisions related to cultural heritage conservation and disaster risk management. |
PDF Full Text Request