台東太麻里溪集水區降雨崩塌對河道淤砂之影響

The Rainfall Landslide Influence on Stream Sediment Deposition in Taitung Taimali River Watershed

鍾斌全

指導教授 ： 陳慶雄

國立屏東科技大學/農學院/森林系所/碩士(2009年)

https://doi.org/10.6346/NPUST.2009.00296

摘要

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。

關鍵字

集水區 ； 日雨量 ； 崩塌 ； 輸砂量

並列摘要

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.

並列關鍵字

Watershed ； Daily Rainfall ； Landslide ； Sediment Deposition

參考文獻

Neill, C. R. (1967) Mean velocity criterion for scour of coarse uniform bed-material. Intern. Assoc. Hydr. Res. 12th Congress, Fort Collins. pp.65-121.

Vanoni, V. A. (1964a) Measurements of critical shear stress. Calif. Inst. Tech., Rep. No. KH-R-7.

中興工程顧問股份有限公司(2006)台東太麻里溪全流域整體治理調查規劃。行政院農業委員會水土保持局第五工程所委託計畫報告。pp.3-57~3-75、3-97~3-103、3-202~3-204。

名碁工程顧問有限公司(2006)太麻里溪整體規劃工作。台東縣政府委託計畫報告。pp.2-1~2-18、3-1~3-18。

交通部台灣區新建工程局(1997)國道南橫公路路線研選計畫。pp.16~35。