Quantifying social vulnerability for flood hazard of households: a case study of Changsha,China

China is exposed to lots of natural hazards and the losses from them have escalated in the past decade,which prompts a reorientation of emergency management systems away from simple post-event response to vulnerability assessment and risk reduction.Therefore,social vulnerability assessment is more important and urgent for current hazard mitigation in China.This paper focuses on social vulnerability in the scale of household and introduces decision tree analysis to assess it.There is an application in the city of Changsha where floods occur often.In order to construct an effective model of household vulnerability assessment,twenty-eight social vulnerability indices,two hazard indices,three biophysical indices and three loss indices were selected.And all of them are collected through on-site questionnaire survey.In this study,social vulnerability of households in different districts of Changsha region is compared and the detail information of households with high vulnerability is shown.