結合土壤雨量指數與頻率比法建構坡地災害潛勢模式

本研究結合土壤雨量指數與崩塌潛勢值來建構坡地災害潛勢模式。土壤雨量指數(SWI)為筒狀模式中三層筒水深總和，可視為土體中儲存之雨量深度。首先收集土砂災例繪製災害涵蓋率曲線，並透過災害涵蓋率訂定SWI警戒值再以災例涵蓋率曲線轉為SWI水文危險度；其次使用頻率比法建構崩塌潛勢值，頻率比法基本假設為崩塌發生與否由崩塌相關因子所決定，後續將崩塌潛勢值正規化得地文危險度。最後結合SWI水文危險度及地文危險度建構坡地災害潛勢值。

關鍵字

筒狀模式；土壤雨量指數；崩塌潛勢分析；頻率比法；坡地災害潛勢值

並列摘要

This study established a hillslope failure susceptibility model for sediment disasters by combining the soil water index (SWI) and landslide susceptibility values to formulate a basis for warning release. The sum of the rainfall depth in the three tank of tank model can be considered as the rainfall retention depth in soil layer. This study collected data of disaster cases and used them to establish lines of disaster coverage. The results indicated that the SWI alert value corresponded to the line of disaster coverage and the hydrological risk was related to disaster coverage. Furthermore, a landslide susceptibility model was constructed involving the frequency ratio method, which is based on landslide factors. The physiographic hazard level was obtained and normalized according to the landslide susceptibility value. This study established a hillslope failure susceptibility model for sediment disasters by combining hydrological risk and frequency ratio based physiographic hazard levels.