GEOGRAPHICAL RESEARCH ›› 2009, Vol. 28 ›› Issue (2): 333-344.doi: 10.11821/yj2009020007

• Earth Surface Processes • Previous Articles     Next Articles

Study on snowmelt runoff and sediment yields in Northeast China

JIAO Jian1, XIE Yun1, LIN Yan1, ZHAO Deng-feng2   

  1. 1. School of Geography|State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China;
    2. Heilongjiang Water Resource Bureau, Harbin 150001, China
  • Received:2008-01-26 Revised:2008-12-23 Online:2009-03-25 Published:2009-03-25
  • Supported by:

    国家重点基础研究发展规划项目(2007CB407203);国家自然科学基金面上项目(40671111)

Abstract:

Severe soil erosion has threatened land resources in Northeast China. Distributed at mid- and high latitudes, soil loss caused by snowmelt runoff plays a main part in soil erosion in this region. But there is little research on it. In this study, the characteristics of snowfall and snow cover were studied by using daily precipitation records from 93 climate stations, and the characteristics of snowmelt runoff and sediment yields were analyzed based on daily runoff and sediment yield data from 27 typical hydrological stations. The results showed that the snow period was 5-8 months and the snow cover period was 3.5-7 months in Northeast China, which prolonged gradually from south to north for both of the periods. The average proportion of snowfall to annual precipitation was 7%-25%, which caused 13.3%-24.9% of snowmelt runoff and 5.8%-27.7% of snowmelt sediment yields over the whole year. Although the snowmelt sediment transport modulus did not have significant relationship with snowfall, the distribution of snowfall and rainfall in a year had great influence on the ratio of snowmelt sediment yields to the year's total. The topography has great impacts on snowmelt sediment transport modulus. The snowfall and snowmelt runoff are less in hilly regions than in mountainous regions, but the sediment transport modulus in hilly regions was 2.9 times higher than that in mountainous regions. The sediment transport modulus (ST) has a good power function with the watershed area (S): ST=797.62S-0.6395. This trend is more apparent in hilly regions, while in the mountainous regions, the relationship between them is complex. The analyzed runoff and sediment yields in this paper were based on the observations in the hydrological stations which did not include deposited part before flowing into the river. It is necessary to strengthen the monitoring of runoff and soil loss during snowmelt season in order to get a better understanding of snowmelt erosion and mechanisms of causing factors.

Key words: snowfall and snow cover, snowmelt season, snowmelt runoff, snowmelt sediment transport modulus, Northeast China