台東太麻里溪集水區之中上游地區地形陡峻、地質脆弱,受豪大雨影響易造成集水區內大量的邊坡崩塌發生,而崩塌之土砂受洪流挾帶堆積於河道下游底床,抬高溪床、縮小通水斷面致洪流溢岸,並改變主流流向沖擊凹岸堤防而使其基礎淘刷破壞,皆是肇始土地與房舍流失災害的原因。集水區邊坡崩塌地產砂量及河道淤砂量皆與降雨量有密切的關係,因此本研究利用航測圖資、衛星影像及實地測量資料,修正過去常用的經驗公式,可有效推求日雨量與崩塌地產砂量及河道淤砂量之關係公式。又根據公式分析結果本集水區年平均崩塌地面積為65.67 ha,年平均崩塌地產砂量為361.2 m3;研究河道年平均淤砂量為6.48 m3,河道年平均淤砂高度為23 cm,這些數據可作為未來河川治理與管理方案決策之參考。
The experimented site is located on the middle and upper reaches of Taimali River watershed in Taitung County. Which terrain is high and precipitous and the geology environment there is weak. Therefore, the rainfall may easily cause many landslides. Sediment of the landslide transports with the stream flowing deposit on the stream bed. That will raises stream bed and shrinks the runoff section. Thus, water of the stream overflow the shore and changes the mainstream’s flow to the impact concave shore embankment to destroy the foundation by washing and brushing. These are the reasons why lands and houses were washed away. The amount of landslides sediment transport and deposit on the stream bed is closely related to the rainfall. In this research, using satellite photography image and field survey data can effectively estimate the amount equation of the relation of daily rainfall, landslides sediment and deposit. According to the analysis result, in this watershed annual landslide area is up to 65.57 ha and amount of soil produced was 3,612,000 m3,deposit height is 23cm and about 64800m3 sediment deposit on stream bed. These data can be adopted to be the possible treatment of building the control work of streams.