为了分析泥石流对沟道冲淤的累积影响效应,根据蒋家沟1999—2014年泥石流沟道断面测量数据对沟道年际冲淤变化特征及影响因素进行了分析。结果表明蒋家沟泥石流沟道断面形态变化主要表现为断面展宽、断面淤积抬高或冲刷降低;沟道宽度变化主要发生于1999—2009年,2009年后沟道宽度相对稳定,沟道冲淤速率逐渐减缓;沟道整体纵剖面曲线呈现下凹型,下凹度不断减小,2009年后下凹度在1.1左右波动,纵剖面整体比降不断增大,2009年后比降增加速率减缓;泥石流输沙规模减小、泥深及流速减小、支沟泥石流汇入、沟道下游排导工程是影响蒋家沟泥石流沟道冲淤的主要因素。研究成果可为泥石流流通及堆积区的防治提供参考。
Abstract
In the aim of investigating the cumulative effect of debris flow on channel morphology, we analyzed the variations and influential factors of erosion and deposition in Jiangjia Gully according to sectional measurements from 1999 to 2014. Results revealed that the channel width increased continuously and the sectional height elevated or decreased depending on the erosion or deposition of channel. The channel width increased mainly from 1999 to 2009, and then remained stable after 2009 when erosion or deposition intensity decreased. Moreover, the curve of longitudinal profile of channel was concave, and the concavity index decreased gradually, fluctuating around 1.1 after 2009. The gradient of channel profile increased gradually, but the increment alleviated after 2009. Decreases in the sediment discharge, depth and velocity of debris flow, and debris flow afflux from tributary, as well as debris flow drainage project in the downstream were dominant factors influencing the channel morphology.
关键词
蒋家沟泥石流 /
沟道年际冲淤 /
下凹度 /
比降 /
冲淤速率
Key words
debris flow in Jiangjia Gully /
inter-annual erosion and deposition /
concavity index /
channel gradient /
erosion and deposition rate
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 唐邦兴,柳素清.四川省阿坝藏族羌族自治州泥石流及其防治[M] .成都:成都科技大学出版社,1993:116-124.
[2] CAINE N.The Influence of Snow and Increased Snowfall on Contemporary Geomorphic Processes in Alpine Areas[G] . STEINOFF H W, IVES J D. Ecological Impacts of Snowpack Augmentation in the San Juan Mountains. Springfield: Fort Collins, 1976:145-200.
[3] DIETRICH W E, DUNNE T.Sediment Budget for a Small Catchment in Mountainous Terrain[J] . Zeitschrift Fur Geomorphologie Supplement, 1978, 29:191-206.
[4] BENDA L.The Influence of Debris Flows on Channels and Valley Floors in the Oregon Coast Range, USA[J] . Earth Surface Processes and Landforms,1990,15(5):457-466.
[5] CENDERELLI D A, KITE J S. Geomorphic Effects of Large Debris Flows on Channel Morphology at North Fork Mountain, Eastern West Virginia, USA[J] . Earth Surface Processes and Landforms,1998, 23(1):1-19.
[6] BERGER C, MCARDELL B W,FRITSCHI B,et al. A Novel Method for Measuring the Timing of Bed Erosionduring Debris Flows and Floods[J] .Water Resources Research,2010,46(2):228-236.
[7] BERGER C, MCARDELL B W,SCHLUNEGGE F.Direct Measurement of Channel Erosion by Debris Flows,Illgraben, Switzerland[J] .Journal of Geophysical Research,2011,116(F1):93-104.
[8] SCHUERCH P,DENSMOREA L,ROSSERN J, et al.Dynamic Controls on Erosion and Deposition on Debris-flow Fans[J] .Geology,2011,39(9):827-830.
[9] 王裕宜,詹钱登,严壁玉.泥石流体的流变特性及其运移特性[M] .长沙:湖南科学技术出版社,2014.
[10] 芦田和男,高桥保,道上正规.河流泥沙灾害以及防治[M] .冯金亭,焦恩泽,译.北京:水利电力出版社,1987:14-16.
[11] 陆中臣,周金星,陈 浩.黄河下游河床纵剖面形态及地文学意义[J] .地理研究,2003,22(1):30-38.
[12] CHEN J,HE Y P,WEI F Q. Debris Flow Erosion and Deposition in Jiangjia Gully, Yunnan, China[J] .Environmental Geology,2005,48: 771-777.
[13] 田连权,吴积善,康志成,等.泥石流侵蚀搬运与堆积[M] .成都:成都地图出版社,1993.
[14] 游 勇,吴积善,程尊兰.蒋家沟下游泥石流导流堤冲决原因及防治对策[J] .灾害学,2001,16(2):14-17.
[15] 韦方强,胡凯衡,崔 鹏,等.蒋家沟泥石流堵江成因与特征[J] .水土保持学报,2002,16(6):71-75.
基金
国家自然科学基金面上项目(41371039);国家重点基础研究发展计划项目(2015CB452704);中国科学院山地灾害与地表过程重点实验室自主支持项目(Y3L1340340)
PDF(3137 KB)
