頻繁土砂災害在和社溪集水區地貌及崩塌演變分析

Long-Term Geomorphologic and Landslide Evolution in the Heshe River Watershed After Frequent Sediment Disasters

吳俊鋐(Chun-Hung Wu) ； 周洲廷(Zhou-Ting Zhou) ； 林政誼(Cheng-Yi Lin)

《中華水土保持學報》 51卷4期 (2020/12) Pp. 147-158

https://doi.org/10.29417/JCSWC.202012_51(4).0003

摘要

本研究對於和社溪集水區進行地貌及崩塌演化分析，和社溪集水區從2001年至2015年間的集水區崩塌率從未低於3.0 %，屬於土砂災害非常活躍的集水區。在2009年莫拉克颱風後，大規模崩塌逐漸縮減，但小規模崩塌個數卻逐漸增加，主要原因是河岸崩塌的增加。和社溪主流河段的土砂淤積主要位於頭坑溪交匯口、二號溪交匯口及神木集水區交匯口，平均淤積深度介於9.17 m至10.7 m。和社溪集水區隸屬於非常活躍與活躍地區的面積仍有1.32 km^2及2.01 km^2，主要位於神木集水區上游。

關鍵字

崩塌演化 ； 崩塌復育 ； 蜿蜒河川 ； 和社溪

並列摘要

This research focused on geomorphologic and landslide evolution in the Heshe River watershed over a period of more than 10 years. The annual landslide ratios from 2001 to 2015 were greater than 3.0%, and the ratio in 2009 reached 6.5 %. The large-scale landslide area from 2010 to 2015 gradually decreased in size, but the frequency of non-large-scale landslides during the same period gradually increased, primarily because of bank erosion. Sediment deposition in the main reach of the watershed from 2004 to 2011 was concentrated in the intersection of Toukeng creek, No. 2 creek, and the Shenmu watershed; the average sediment deposition depth ranged from 9.2 m to 10.7 m. The areas of active and highly active landslides were 2.01 km^2 and 1.32 km^2, respectively, and were located upstream of the Shenmu watershed.

並列關鍵字

landslide evolution ； landslide recovery ； sinuous river ； Heshe river watershed