Abstract:

Based on GIS technology and the national planning data about prevention of mountain torrent disaster , the risk of mountain torrent disaster, vulnerability and risk degree of Sichuan province were quantified and analyzed in this paper by using the concept of natural disaster risk .According to the general principles of the regionalization theory and the regionalization classification of national mountain torrent disasters, the risk regionalization of Sichuan province was put forward. Results show that the risk levels of mountain torrent disaster in Sichuan province can be divided into 5 kinds: low risk, low-middle risk, middle risk, middle-high risk, and high risk. The percentage of area of the five risk levels accounting for total area of the province is 59.9%, 12.8%, 14.9%, 5.9% and 6.5%, respectively. In the Sichuan basin and the surrounding regions, risk level of mountain torrent disaster is high, for area with the risk level middle or above takes up nearly 80% of total area of these regions .Furthermore, mountain torrent disaster in mountain regions of Qinling and Dabashan is relatively serious, for the risk level is middle or above in nearly 18% of total area of the mountain regions. Finally, risk levels of mountain torrent disaster in several other regions is not high, most of them are low risk and low-middle risk.

Key words: mountain torrent disaster, risk assessment, risk regionalization, GIS technology, vulnerability index