Study on Vulnerability Assessment Model for Rainfall-induced Landslide Potential Areas
| Autor: | Hui-Wen Tsai, 蔡惠雯 |
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| Rok vydání: | 2017 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 105 The unstable geology in the slope and frequent seismic activities of Taiwan make these areas vulnerable to landslides and other sediment disasters during typhoons and heavy rains. Due to the growth of population and change of economic environment, the development and utilization of slope land is inevitable. Thus, in landslide sensitivity areas, the possibility of disaster increases, while the adjustment capacity relatively decreases. Especially, under the extreme rainfall, the large landslides of slope were developed and the natural environmental conditions of mountain areas were changed dramatically. Therefore, the assessment of vulnerability for rainfall-induced landslide potential areas is essential to disaster prevention. Some areas of Sandimen and Wutai townships of Pingtung County in southern Taiwan were selected as study areas. Using GIS, the spatial and attribute database of disaster history records and relevant data layers were constructed. Based on the genetic adaptive neural networks with texture analysis, the satellite images were interpreted to obtain surface conditions and hazard log data. Meanwhile, using the multivariate hazards evaluation method, the landslide potential assessment model was constructed. Then, a landslide potential map was drawn combined with the GIS. In addition, according to the items of exposure, sensitivity, adjustment, landslide potential and mountainous village characteristics, a framework of vulnerability analysis was established. Finally, using the relational matrix analysis method combined the spatial analysis of GIS, the vulnerability analysis was performed and the vulnerability gradation map was drawn. Results of image classification show that the values of coefficient of agreement for four different time periods in the years of 2009 and 2013 are at intermediate-high level. Considering the landslide potential influencing factors of natural environment, land disturbance and rainfall, the result indicates that weight of geology is the highest, followed by weights of slope disturbance, distance to the stream, effective accumulate rainfall, slope, elevation, and aspect. The accuracy of predicted potential of landslide is up to 70% compared with historical records. Furthermore, the results suggest that the proposed method and procedures can be an effective tool for vulnerability analysis of rainfall-induced landslide potential areas. The findings can be a reference for the regional planning of disaster prevention. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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