Abstract:

Assessing the difficulty of early-warning mountain torrent flood disaster is a basic research in the study of mountain flood disaster prevention in China. In this study, we built the assessment index system by using geostatistics method based on historical disasters, geographical background, and socio-economic data. The assessment index system includes the types of the torrent flood processes, underlying surface complexity and maintainability and performability of equipment. Analytic Hierarchy Process was employed to give weights to various indicators and the assessment model was obtained. The model was applied to assess the difficulty of early-warning torrent flood disaster in the Yangtze river basin. Results showed that areas difficult to warning are mainly concentrated in the south of Gansu Province, middle Sichuan province, the north of Yunnan, northeast of Guizhou, Northwest of Hubei, and large parts of Chongqing. These areas are frequently subjected to landslides and debris flows with high mountains and steep slopes unaccessible and high costs of installing and maintaining equipment as well as fiscal difficulty. Qinghai, Sichuan basin, and the middle and lower reaches of Yangtze river are less difficult to warn. The assessment results are consistent with field investigation of typical regions. The research results may provide new perspective and basis for policy-making on the control of torrent flood disasters in China.

Key words: Yangtze river basin, mountain torrent disaster, warning difficulty, analytical hierarchy process, flood prevention and disaster mitigation