An Establishment of Sediment Disaster Risk Assessment Model for Hualien County in the Eastern Taiwan

摘要

The topography of slope lands at Hualien County in eastern Taiwan is quite steep combined with fragile geological structure.Hsiukuluan and Shoufeng watersheds located at Hualien County were selected as two study areas in this research.Mechanism,behavior,and scale of these sediment disasters were analyzed to rule out their interaction with the factors mentioned above and the extent of the debris flow.In the study,application of global positioning systems (GPS) would be necessary to collect all fundamental information,including site positioning,disaster scale investigation,and other disaster related factors determination.Geographic information systems (GIS) was used to establish the sediment related disaster database system based on mathematic methods.The data collected from 131 combat engineering structures on hillslope and their surrounding disaster prevention measures were divided into 8 major affective factors by using GPS/GIS integration.Both Multivariate Analysis and Multiple Linear Regression Analysis were introduced to establish the sediment disaster risk assessment model.An accuracy of 80％ can be expected for the model.All results established by this study can help Hualien County set up its own disaster prevention system and keep well development of the city and rural in the near future.