運用ALOS PALSAR雷達影像之差分干涉成果於潛在崩塌地調查－以眉溪流域為例

Investigation of Potential Landslide with Differential Interferometry Using ALOS PALSAR-An Example of May River Watershed

王國隆(Kuo-Lung Wang) ； 林俊廷(Jun-Tin Lin)

《航測及遙測學刊》 19卷3期 (2015/01) Pp. 253-265

https://doi.org/10.6574/JPRS.2015.19(3).7

摘要

台灣由於山坡地佔全島百分之七十以上的面積，且因菲律賓海洋板塊持續碰撞歐亞板塊，因此每年由太平洋熱帶氣流形成的颱風和板塊運動造成的地震所引發的災害發生頻繁，然而對降雨導致的山崩進行調查，需要耗費相當大的人力和物力，山崩調查時除了現場調查之外，還需要配合光學衛星影像及航空照片進行判釋，目前採用光學影像判釋的方法發展已可獲得相當高的正確率，但對於災前的調查或具有滑移潛勢的山坡地，仍缺乏具有系統化的方法。因此本研究提出採用差分干涉合成孔徑雷達影像分析方法，試圖以雷達差分干涉技術，利用時序性的合成孔徑雷達資料配合數值地形去除地形效應，用解算分析干涉成果來劃定潛在滑移邊坡，以圈繪出的潛在滑移邊坡與光學衛星影像判釋成果進行比對，將可驗證差分干涉技術具有發現潛在崩塌地之預警能力。本研究以眉溪流域為研究區域，眉溪流域位於南投縣埔里鎮至仁愛鄉之間，流域內歷年來發生多次崩塌及土石流災害，除直接造成之災害外，產生之土石輸送至眉溪下游後造成河道淤積，容易引發二次災害，研究結果顯示，差分干涉技術於發現潛在崩塌地具有相當高之可信度，未來可將此一方法運用於其他山坡地的潛在崩塌地調查，並作為土地規劃利用之參考。

關鍵字

雷達影像 ； 差分干涉 ； 潛在崩塌地

並列摘要

Slope land area covers more than 70% of Taiwan. Landslide hazards happen frequently owing to collision of Philippine sea plate and Eurasian plate in terms of earthquakes and typhoons formed by tropical cyclone. Heavy rainfall induced landslide investigation requires huge amount of budget. Landslide investigation usually adopts field investigation, identification from optical satellite images and aero photos. Even optical image based landslide identification has very high accuracy, but the investigation of landslide before total failure lacks of systematic methodology. Thus a potential landslide investigation is proposed in this research. Potential landslide area is defined with differential interferometry radar imagery, which topographic effect has been removed from digital elevation model. The potential landslide map is defined with fringe and compared with landslide area defined from optical satellite imagery. The study is trying to provide evidence that potential landslide map defined by differential interferometry has earlier finding of landslides. Study area is selected as May River watershed. May River watershed locates between Renai and Puli township. Landslides and debris flow happen frequently in this watershed. Despite of direct hazard induced by landslide, secondary hazard attacked with debris flow located in channel is another important issue. The result of this study shows that potential landslide investigation with differential interferometry has high reliability and can be used as other potential landslide investigation and reference of land use plan.

並列關鍵字

Radar Imagery ； Differential Interferometry ； Potential Landslide