TY - JOUR
T1 - Estimating woody debris recruitment in a stream caused by a typhoon-induced landslide
T2 - A case study of typhoon Lionrock in Iwaizumi, Iwate prefecture, Japan
AU - Chaithong, Thapthai
AU - Komori, Daisuke
AU - Sukegawa, Yuto
AU - Anzai, Satoshi
N1 - Funding Information:
This study was supported by the Japanese Society of Civil Engineering, the Society for the Promotion of Construction Engineering, and the Social Implementation Program on Climate Change Adaptation Technology (SI-CAT).
Publisher Copyright:
© 2018 The Author(s).
PY - 2018/10/9
Y1 - 2018/10/9
N2 - A landslide can generate large amounts of debris in the form of boulders, cobbles, soil, and wood. The woody debris produced by a landslide flows into a downstream river or village; it can form obstructions in the stream and destroy houses. In this study, we aimed to develop a procedure for estimating woody debris recruitment into streams following a landslide. Understanding the volume of woody debris can help predict and prevent hazards from this debris. The proposed procedure combines a shallow landslide model, tree density data, and observational data following landslide occurrence. The study site is a sub-watershed of the Omoto River watershed in the town of Iwaizumi in Iwate prefecture in Japan; this town was affected by Typhoon Lionrock in 2016. Typhoon Lionrock delivered over 200mm of rainfall in 24 h and induced many landslides. Based on field surveys, we found that approximately 524 m3 of woody debris jammed the narrow section under a railway bridge (including voids) and approximately 178 m3 of woody debris to formed a dam in the stream channel of the target watershed (including voids). Using the proposed protocol, we estimate that woody debris recruitment to the stream was approximately 638 m3.
AB - A landslide can generate large amounts of debris in the form of boulders, cobbles, soil, and wood. The woody debris produced by a landslide flows into a downstream river or village; it can form obstructions in the stream and destroy houses. In this study, we aimed to develop a procedure for estimating woody debris recruitment into streams following a landslide. Understanding the volume of woody debris can help predict and prevent hazards from this debris. The proposed procedure combines a shallow landslide model, tree density data, and observational data following landslide occurrence. The study site is a sub-watershed of the Omoto River watershed in the town of Iwaizumi in Iwate prefecture in Japan; this town was affected by Typhoon Lionrock in 2016. Typhoon Lionrock delivered over 200mm of rainfall in 24 h and induced many landslides. Based on field surveys, we found that approximately 524 m3 of woody debris jammed the narrow section under a railway bridge (including voids) and approximately 178 m3 of woody debris to formed a dam in the stream channel of the target watershed (including voids). Using the proposed protocol, we estimate that woody debris recruitment to the stream was approximately 638 m3.
KW - Debris flow
KW - Landslide
KW - Typhoon
KW - Wood debris
KW - Woody debris dam
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U2 - 10.1080/19475705.2018.1490822
DO - 10.1080/19475705.2018.1490822
M3 - Article
AN - SCOPUS:85063511905
VL - 9
SP - 1071
EP - 1084
JO - Geomatics, Natural Hazards and Risk
JF - Geomatics, Natural Hazards and Risk
SN - 1947-5705
IS - 1
ER -