Topographic influence on landslides characteristics and implication for risk management in upper Manafwa catchment, Mt Elgon Uganda
Topographic influence on landslides characteristics and implication for risk management in upper Manafwa catchment, Mt Elgon Uganda
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DOI：
10.1186/s40677-020-00160-0
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发表时间：
2020-09-24
影响因子：
4.8
通讯作者：
Nedala, S.
中科院分区：
文献类型：
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作者：
Nakileza, B. R.;Nedala, S.
本研究旨在探讨地形对热带山地滑坡属性的影响，并探讨其对风险管理的启示。在实地调查的基础上，以案头研究为补充，建立了滑坡清查数据库。地形参数来源于研究区30m分辨率的STRM DEM。数据分析在Arc GIS 10.5环境下进行。利用频率比模型分析了滑坡与地形条件因子的关系。结果表明，大部分滑坡分布在海拔1500 ~ 1800ma.s.l范围内。在中等陡峭的斜坡(15 （o)-20(o)）在凹曲率（空心）。浅层滑坡以泥石流和泥石流为主。大多数边坡破坏发生在新疤或旧疤的中上坡位置。一些大型滑坡的快速沉积最终流入溪流，从而破坏了水质。地形参数的研究结果具有一定的意义，但当地居民对滑坡风险的管理普遍不足。任何有效的滑坡风险管理工作都应优先绿化敏感的地形洼地和旧伤疤，特别是在中上坡位置。
This study aimed to characterize the topographic effect on landslides attributes and explore the implications on risk management in a tropical mountainous environment. A database was constructed based on landslide inventory from field surveys supplemented by desk research. The topographic parameters were derived from STRM DEM of a 30m resolution for the study area. The analysis of the data was conducted in Arc GIS 10.5 environment. The relationship between landslides and topographic conditioning factors was analysed using the Frequency Ratio model. Results revealed that most landslides were distributed within the altitudinal range of 1500 to 1800ma.s.l. on moderately steep slopes (15 (o)-20(o)) in concave curvatures (hollows). Shallow slides mainly debris flows and debris slides were predominant. Most slope failures were initiated on mid to upper slope positions in either new or old scars. Some runout depositions of large slides ended in streams thus undermining water quality. The findings on topographic parameters have implications and yet landslide risk management by the local population was generally inadequate. Any efforts toward effective landslide risk management should prioritise greening the sensitive topographic hollows and old scars particularly on mid to upper slope positions.