Socio-demographic determinants of flood risk perception disparities: A comparative study of subjective and objective risks in Nanjing, China

• Socio-demographic factors are pivotal in explaining regional differences between subjective and objective flood risks. • Explain the difference between subjective and objective flood risk. • Utilize SPSS and GIS to process and analyze data, investigating factors shaping public flood risk perception through integrated methods. Global warming and urbanization worsen flood disasters, posing significant threats to human life and property. Both subjective and objective risk evaluations are of great significance in reducing the influence of calamities and devising comprehensive plans for risk governance. Although some studies have identified differences between subjective and objective risks, a detailed analysis of their underlying causes is lacking. These disparities in risk perception can lead to an uneven allocation of resources. Factors influencing risk perception directly or indirectly impact a region’s potential resilience and preparedness for disasters. Socio-demographic factors emerged as critical determinants of flood risk perception disparities. This study aims to integrate both risk assessments to explore the reasons behind these differences. Using six central districts in Nanjing as a case study, the research utilized SPSS and GIS for processing the assessments, and applied a comprehensive analysis method to probe into the elements that have an impact on how people perceive the risk of floods. The findings indicated that Jianye and Gulou districts had high objective risk but low subjective risk, while Qinhuai and Yuhuatai presented low objective risk but high subjective risk. Notably, socio-demographic variables such as gender, education, flood experience, and disaster education exhibited district-specific influences on risk perception, explaining the differences between subjective and objective risks. Additionally, the factors influencing how residents perceive flood risk varied across districts. These discoveries can assist governments in implementing targeted flood protection measures and developing comprehensive rescue strategies that address both physical vulnerabilities and psychological perceptions of risk.