神木集水區自85 年賀伯颱風起，歷經多場強颱與地震事件，致使集水區內歷年崩塌地面積
有增無減，所引致大規模土砂產量危及下游保全對象。本文應用遙測技術，分析神木集水區歷
年重大土砂災害之衛星影像崩塌地時空間變遷；結果可以發現，莫拉克颱風後神木集水區以上
游出水溪與愛玉子溪等兩集水區土砂災情最為慘重，其中愛玉子溪集水區新增崩壞比更高達
22%；經本年度凡那比颱風後，再次爆發土石流；赴現地實際勘查，河道中游仍堆積大量土砂，
建議有關單位應持續監測河相及臨溪崩塌坡面之地形變化，供以實施防災應變及疏散避難策略。

Landslides have been triggered frequently during typhoon season in Shemu watershed. They would transform a great deal of sediment materials and endanger the downstream area. This study applies remote sensing technology to analyze spatial and temporal evolution of landslides during 1996 to 2009. Based on the above, sediment disaster induced typhoon Morakot in 2009 inflicts severe damages to Chu-shui and Aiyuzih creeks in Shemu watershed, which the ratio of increment landslide in Aiyuzih creeks increases up to 22%. In October 2010, Typhoon Fanapi hits Shemu watershed again and causes debris flows. That results in large amount of sediment materials still deposited in mid-stream of Aiyuzih creek from field survey. It is suggested that government should pay more attention to monitor the topological changes of river and hillslopes and implement emergency action and disaster prevention when sediment disasters happen.