Research on the engineering geomorphological investigation methods for planning countermeasures against sediment-related disasters in the Nepal Himalaya

尼泊尔喜马拉雅地区泥沙灾害规划对策的工程地貌调查方法研究

• 批准号: 12680460
• 负责人: HIGAKI Daisuke
• 金额: $ 2.18万
• 依托单位: Hirosaki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12680460/
• 关键词: Himalaya; Nepal; Soil erosion; Bank erosion; River course shifting; Landlslide; Hazard map; Sediment related disaster; 河岸侵食; 流域管理; ランドスライド; 地すべり地形; ハザードマップ

This study aims to propose engineering geomorphological investigation points for countermeasure planning against erosion and sedimentation disasters through analysis of present and past geomorphic processes in the Nepal Himalaya1)By monitoring rate and processes of gully erosion, surface erosion and vegetation recovery for ten years, we evaluated the various adopted countermeasures. Based on it, selecting methods of erosion control measures by investigating stages of gully and rill development is basically conceptualized.2)Causes of river course widening in the Sub-Himalaya(Siwalik Hills) have been studied through monitoring both erosion of slopes/stream banks and run-off processes as well as geomorphological evolution processes. Extreme flash floods with short tune of run-off concentration have occurred due to dense network of drainage systems due to weak and young geological strata. Huge sediment production from slopes and banks equivalent to the denudation rate of at least 5mm/year in depth is estimated. They are the main causes of river course widening. Land coverage change in a watershed may also be the cause of it.3)Deep-seated landslide distribution maps have been prepared by aerial photo interpretation in the Lower Himalaya and partly in Sub-Himalaya. It is proposed through the statistical analysis that landslide hazardous slopes can be detected by combination of geology such as lithology and structure and slope angle.4)A GIS-based landslide hazard zonation method is also proposed from the statistical analysis on the relation between landslide occurrences and then* physiographical attributes.

通过对尼泊尔喜马拉雅地区过去和现在地貌过程的分析，提出了防治冲淤灾害的工程地貌调查要点。1）通过对尼泊尔喜马拉雅地区10年来沟蚀、地表侵蚀和植被恢复的监测，对各种防治措施进行了评价。在此基础上，初步形成了通过调查沟、细沟发育阶段来选择侵蚀控制措施的方法。2）通过对坡岸侵蚀、径流过程和地貌演变过程的监测，研究了喜马拉雅山以南（西瓦利克山）河道加宽的原因。由于地质层软弱和年轻，排水系统网络密集，发生了径流集中时间短的极端山洪。据估计，斜坡和河岸产生的大量沉积物相当于至少5毫米/年的深度剥蚀率。它们是河道拓宽的主要原因。流域内土地覆盖的变化也可能是造成滑坡的原因。3）通过航空照片判读，绘制了喜马拉雅山下部和部分喜马拉雅山以南地区的深层滑坡分布图。通过统计分析，提出了结合岩性、构造、坡度等地质特征进行滑坡危险性识别的方法。4）通过滑坡发生与地貌属性的统计分析，提出了基于GIS的滑坡危险性区划方法。

项目成果

H.Yagi, T.Abe: "Landslide distribution in the mid-eastern part of the Lower Nepal Himalayas with special reference to geology and geomorphology"Abstract volume of Int.Conference on the Great Himalayas : Climate, Health, Ecology, Management and Conservatio

H.Yagi, T.Abe：“尼泊尔下喜马拉雅山中东部地区的滑坡分布，特别涉及地质和地貌”大喜马拉雅国际会议摘要卷：气候、健康、生态、管理和保护

D.Higaki: "Landslides in the late Quaternary deposits in the Bhote Koshi area, central Nepal"Journal of Nepal Geological Society. 22. 505-512 (2000)

D.Higaki：“尼泊尔中部博特科西地区晚第四纪沉积物中的山体滑坡”尼泊尔地质学会杂志。

S.K.Ghimire: "Measurement of surface, rill, gully erosion and streambank erosion in a Siwalik watershed of Nepal"東北地域災害科学研究. 39. 171-176 (2003)

S.K.Ghimire：“尼泊尔 Siwalik 流域地表、沟渠、沟渠侵蚀和河岸侵蚀的测量”东北地区灾害科学研究，39. 171-176 (2003)。

Higaki, D., K.K.Karki, C.S.Gautam: "Soil erosion control measures on degraded sloping lands-A case study in Midlands of Nepal."Abstract volume of Int.Conference on the Great Himalayas : Climate, Health, Ecology, Management and Conservation. 39. (2004)

Higaki, D.、K.K.Karki、C.S.Gautam：“退化坡地的土壤侵蚀控制措施 - 尼泊尔中部地区的案例研究。”大喜马拉雅国际会议摘要：气候、健康、生态、管理和保护

V.Dangol: "Landslide hazard mapping in Nepal : Case studies from Marin Khola (Eastern Nepal) and Syangja District (Western Nepal)"Int.Congress Interpraevent 2002 in the Pacific Rim. 2. 607-618 (2002)

V.Dangol：“尼泊尔山体滑坡灾害测绘：马林科拉（尼泊尔东部）和 Syangja 区（尼泊尔西部）的案例研究”2002 年环太平洋地区国际会议 Interpraevent。