崩塌地植生復育對集水區產砂之影響—以太麻里溪為例—

Effect of landslide vegetation recovery on sediment yield in a watershed - A case study of Taimali River Basin -

王亮心(Wang Liang-Hsin)

指導教授 ： 李錦育 ； 陳金諾

國立屏東科技大學/工學院/水土保持系所/碩士(2020年)

https://doi.org/10.6346/NPUST202000051

摘要

本研究應用集水區地文性土壤沖淤模式，模擬演算不同重現期距2年、5年、10年、25年、50年、100年以及200年之一日暴雨事件下，太麻里溪流域之崩塌地於不同植生復育程度對集水區沖蝕量、產砂量及河道輸砂之影響。由模擬演算結果可知，崩塌地從裸露覆蓋率C=1.00、植生復育至緩生作物覆蓋達C=0.50、草本植被覆蓋達C=0.20、草本植被覆蓋達C=0.05及複層植被覆蓋達C=0.01時，太麻里溪流域沖蝕量平均減少率，分別為45.80%、73.22%、86.95%及90.61%；流域產砂量減少率，分別約38.92%、72.46%、86.80%及90.62%，結果顯示植生復育對集水區沖蝕及產砂之重要性。本研究應用演算之流量及輸砂率結果建立太麻里溪流域崩塌地於不同植生復育覆蓋率，各控制點流量與輸砂量之率定曲線，結果可知，流量及輸砂率與集水區水文、地文條件之改變有密切關係，如流量、坡度、崩塌、植生復育率等。本模式建置之流量－輸砂率關係式可輔助長期缺乏水文觀測資料之太麻里溪流域進行產砂量推估，亦可提供太麻里溪後續相關研究之參考。

關鍵字

集水區地文性土壤沖淤模式 ； 崩塌 ； 植生復育 ； 產砂量

並列摘要

In this study, Physiographic Soil Erosion-Deposition (PSED) model was applied to simulate the amount of erosion and sediment yield under different vegetative coverage rate in the collapse of the Taimali river basin for design rainfall of one day storms under various return periods (2 year, 5 year, 10 year, 25 year, 50 year, 100 year, 200 year). The results indicate that the vegetation recovery at the landslide area from the bare state to slow-growing crop cover up to vegetative coverage rate 0.5 (C = 0.50), herbaceous vegetation cover up to C = 0.20, herbaceous vegetation cover up to C = 0.05 and compound vegetation cover up to C = 0.01. The reduction rate of total erosion in the Taimali river basin decreased by an average of about 45.80%, 73.22%, 86.95% and 90.61%, and the total sediment yield in the basin decreased by about 38.92%, 72.46%, 86.80% and 90.62%, respectively. Therefore, vegetation recovery is important to erosion and sediment yield in the watershed. In addition, the rating curve of discharge and suspended sediment transport rate of each control points of Taimali river for the different vegetative coverage rate were established. The results show that the discharge and suspended sediment transport rates related well with the change in hydrological and geographic factors (for example, discharge, slope, landslide, vegetation recovery rate, etc.,). The discharge and suspended sediment transport rate relationship types of this model can provide a reference for related research of Taimali river.

並列關鍵字

PSED Model ； Landslide ； Vegetation recovery ； Sediment yield

參考文獻

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