GEOGRAPHICAL RESEARCH ›› 2007, Vol. 26 ›› Issue (4): 745-754.doi: 10.11821/yj2007040011

• Environment and Ecology • Previous Articles     Next Articles

One new sediment yield model for single storm events and its application at annual time scale

ZHENG Ming-guo1,2,3, CAI Qiang-guo1,2, CHENG Qin-juan1,2,3   

  1. 1.
    1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;

    2. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101,China;
    3. Graduate School of the Chinese Academy of Sciences, Beijing 100039,China
  • Received:2006-08-09 Revised:2006-12-20 Online:2007-07-25 Published:2007-07-25
  • Supported by:

    国家自然科学基金重点项目 (40635027);国家重点基础研究发展计划973项目 (2007CB407207);中科院地理科学与资源研究所知识创新工程项目 (CXIOG-A04-10)

Abstract: The loess gullied-hilly area of the Loess Plateau in North China is one of the most severely eroded regions in the world with a mean annual soil loss rate exceeding 10000t/km2.Based on the observed data here from two stations, the relationship between runoff and sediment yield is examined for single storm events. In the study area, sediment concentration keeps stable when flow discharges are in excess of some critical values, and mean sediment concentration for single flood events mainly depends on the heavy-discharge stage in flood duration. Thus, the mean sediment concentration also keeps stable for heavy flood events. Therefore, one new runoff-sediment relationship model is established for specific watershed:M=Ch,where M is area-specific sediment yield, h is runoff depth. Furthermore, this model has excellent applicability due to the importance of extreme events for soil loss in the study area. The results of the model applied to the annual timescale showed that the model can predict the annual sediment yield very well for the watershed without base flow; and for the watershed where base flow exists, the model can also obtain a good estimation in wet year using the total runoff volume occurred in flood season.

Key words: runoff-sediment relationship, sediment yield, model, Loess Gullied-hilly Area