Gully and tunnel erosion in the hilly Loess Plateau region, China
详细信息查看全文 | 推荐本文 |
摘要
Although gully development is frequently observed to be associated with piping and tunnel erosion in many parts of the world, there is a lack of detailed studies on their spatial interactions. Such studies not only contribute to developing geomorphic theories on the evolution of both hillslopes and drainage networks but also are useful to design effective control measures of erosion. The present study aims to examine the interactions between gully development and tunnel erosion in the hilly Loess Plateau region of northern China. Firstly, gullies, tunnel inlets and mass movements in the 9.1 km2 Wangjiagou watershed were mapped through aerial photo interpretation and reconnaissance surveys. Secondly, detailed field studies were carried out to investigate the interactions between gully development and tunnel formation processes in the selected gullies. Thirdly, the physiographic variables of gullies, derived from GIS and field measurements, were analyzed to identify differences between tunneled and untunneled gullies.

A total of 704 channels, 967 tunnel inlets and 547 mass movements were identified in the study watershed. On the basis of their location and morphology, all the channels were classified into four types: headwater gullies, hillside gullies, valleyside gullies and ephemeral river channels. Tunnels are associated with 79%of headwater gullies, 48%of hillside gullies, 3%of valleyside gullies and none of ephemeral river channels. Mass movements are dominated by falls in headwater gullies, falls and slides in hillside gullies, and soil creeps in ephemeral stream channels. Statistical tests indicate that there are significant differences in physiographic variables between tunneled and untunneled gullies. Tunnel formation in gullies is intricately affected by topographic conditions, land uses, knickpoint distribution, soil materials and mass movements.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700