Debris‐flow fan development and geomorphic effects in alpine canyons under a changing climate

Author:

Hou Weipeng12,Yu Guo‐An1ORCID

Affiliation:

1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

2. College of Resources and Environment University of Chinese Academy of Sciences Beijing China

Abstract

AbstractDebris flows in alpine environments are prone to occur in the context of global climate change (i.e., elevated air temperature and higher frequency of strong precipitation events). (Alluvial) Fans often develop at the outlet of tributaries after high‐intensity debris flows. Most debris‐flow fans in alpine canyon areas extend directly to the main river channel and become the forefront of the interaction between the tributary gully and the main river channel. Clarifying the development processes/dynamics, evolutionary mechanisms and driving factors of alluvial fans would shed light on understanding the geomorphological effects and genesis of river valleys in alpine canyon areas. Here, we report the development of debris‐flow fan at the outlet of the Tianmo Gully, a formerly hazard‐free but currently hazard‐active tributary of the Parlung Tsangpo Basin, Southeast Tibet, where debris flows have occurred frequently in the last two decades. Combining remote‐sensing images, DEM data, UAV aerial photography, RTK topographic survey and other fieldwork, the development processes and morphological characteristics of the Tianmo fan under the influence of four large debris flows were analysed. Both primary events (described as episodic debris‐flow events characterized by high‐magnitude mass movement) and secondary events (corresponding to perennial stream flow processes with much lower sediment concentrations) affected the development of the Tianmo fan. Episodic debris‐flow events drastically shape the macroscopic morphology of the fan, with rapid deposition and expansion of the fan body, whereas perennial stream flow processes slowly modulate the fan during the intermittent period between debris flows, mainly with gradual retrogressive incision and lateral migration of flow channel on the fan body. Influenced by the strong sediment‐transport process of debris flows and the alluvial fan development, the planform of the Parlung Tsangpo River evolved from a relatively narrow and single‐thread pattern to an alternating‐wide‐and‐narrow pattern, with a corresponding staircase‐like longitudinal profile.

Funder

National Natural Science Foundation of China

Publisher

Wiley

Subject

Earth and Planetary Sciences (miscellaneous),Earth-Surface Processes,Geography, Planning and Development

Cited by 2 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3