Journal of Geographical Sciences ›› 2009, Vol. 19 ›› Issue (3): 321-330.doi: 10.1007/s11442-009-0321-8

• Climate and Environmental Change • Previous Articles     Next Articles

Effect of grass coverage on sediment yield in the hillslope-gully side erosion system

LI Mian1, YAO Wenyi1, DING Wenfeng2, YANG Jianfeng1, CHEN Jiangnan1   

  1. 1. Yellow River Institute of Hydraulic Research, Key Lab of Yellow River Sediment Research of Ministry of Water Resources, Zhengzhou 450003, China|
    2. Yangtze River Scientific Research Institute, Wuhan 430010, China
  • Received:2008-06-23 Revised:2008-09-20 Online:2009-06-25 Published:2009-06-25
  • Supported by:

    National Basic Research Program of China, No.2007CB407201; National Key Technology R&D Program, No.2006BAB06B01-06; Science and Technique Development Foundation of YRIHR, No.200603

Abstract:

By scouring experiments, the changeable process and characteristics of sediment yield in the hillslope-gully side erosion system with different coverage degrees and spatial locations of grass were studied. Five grass coverage degrees of 0, 30%, 50%, 70%, 90%, three spatial locations of grass (upslope, mid-slope, low-slope) and two water inflow rates of 3.2 L/min, 5.2 L/min were applied to a 0.5 by 7 m soil bed in scouring experiments. Results showed that the sediment yield decreased with the increase of grass coverage degree at 3.2 L/min water inflow rate in scouring experiments and the sediment yield with different grass locations on the sloping surface was in the order of upper > middle > lower. At 5.2 L/min water inflow rate, the differences of sediment yield among various grass coverage degrees were increased, whereas the changeable tendency of sediment yield with different grass locations on the whole sloping surface was not very obvious. The proportion of sediment yield from the gully side increased in an exponential relationship with the increase of grass coverage degree. When the grass was located on the lower position of hillslope, the influence for accelerating gully erosion is the greatest.

Key words: grass coverage, hillslope-gully side erosion system, scouring experiment, sediment yield