The relationships between landslide and sediment discharge in different typhoon along the watershed of Shimeng reservoir
Date Issued
2007
Date
2007
Author(s)
Yuan, Cheng-Wei
DOI
zh-TW
Abstract
Abstract
After the catchments of Shimeng reservoir go through typhoon Herb, typhoon Toragi, typhoon Aere, and typhoon Matsa, the newborn landslide rate dropped to 46% from 92%, the reactive landslide rate increased from 19% to 53%. The type of landslide is mainly on smaller landslide which less than 2000m2 . Probability distribution in upslope area at the lowest spot reached by landslide shows that there are materials of 77% and 94% accumulate on the hillslopes after four typhoon event. Most of landslide happened on the area that slope between 30° to 50°, the probability between 69% to 76%. from the statistical analysis of landslide, we found that most of landslide concentrated on Aoti formation, Datongshan formation, and Gangou formation, More than 90% of whole landslide area in the watershed of Shimeng reservoir.
The sediment discharge from 1980 to 2004 of the catchments of Shimeng reservoir is 13.7 Mt/yr. In four typhoon event , The sediment discharge during typhoon Aere is 2.5 Mt/yr which is 1.6 times of 1.6 Mt/yr during typhoon Herb. The turbidity during typhoon Aere is 1.5 ten thousand ntu that transform sediment discharge , and the turbidity that field survey in Shimeng reservoir is 12 ten thousand ntu. After compare with each other, result shows that The turbidity in Shimeng reservoir has a great relationship to the sediment in the bottom of reservoir.
Subjects
石門水庫
山崩
輸砂量
颱風
Shimeng reservoir
landslide
sediment
typhoon
Type
thesis