• 水文与水资源 •

### 长江上游输沙尺度效应研究

1. 中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室,北京 100101
• 收稿日期:2008-01-18 修回日期:2008-05-06 出版日期:2008-07-25 发布日期:2008-07-25
• 作者简介:师长兴(1963-),男,河北正定人,研究员,博士生导师。主要从事河流地貌、流域物质迁移与环境变化研究。E-mail:shicx@igsnrr.ac.cn
• 基金资助:

国家重点基础研究规划(973)项目(2003CB415202);水利部公益性行业专项经费项目(2007SHZ0901034);国家自然科学基金项目(批准号:40671019)。

### Scaling effects on sediment yield in the upper Yangtze River

SHI Chang-xing

1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
• Received:2008-01-18 Revised:2008-05-06 Online:2008-07-25 Published:2008-07-25
• Supported by:

国家重点基础研究规划(973)项目(2003CB415202);水利部公益性行业专项经费项目(2007SHZ0901034);国家自然科学基金项目(批准号:40671019)。

Abstract:

Scaling effects on sediment yield in the upper Yangtze River are investigated through constructing relationships between the specific sediment yield (SSY) and drainage area and factors influencing soil erosion based on data of drainage basins upstream of 268 hydrological stations. The factors influencing soil erosion used in the study are those in the Revised Universal Soil Loss Equation (RUSLE) and are calculated from DEM, rainfall, landuse, soil type data banks for the upper Yangtze River. Results show that there is a negative power relationship between SSY and the drainage area of all the gauged drainage basins in the upper Yangtze River and this relationship can be ascribed to the changes in rainfall erosivity factor R and soil erodibility factor K in RUSLE with the drainage area. Between the drainage area of 104-1.58×105km2 exists an abrupt decline of SSY with the increase of drainage area and it is a main component of the overall decreasing trend of SSY with the drainage area. In the regression relationship of SSY with the drainage area and all RUSLE factors, SSY is positively and exponentially related with the drainage area, revealing that deposition of eroded sediment occurs in a short distance in the upper Yangtze River. The relationships of SSY with the drainage area and RUSLE factors of the drainage basins of the main first-order tributaries of the upper Yangtze River are also constructed and analyzed. The results show different relationships for different tributaries because of different reasons. The scaling effects on sediment yield and causes for changes in SSY with the drainage area in the Jingsha basin are similar to those in the whole upper Yangtze River. The causes for changes in SSY with the drainage area in the Min-Tuo (Minjiang-Tuojiang) basin are also associated to the changes in factors R and K with the drainage area, but SSY is negatively related with the drainage area in the multiple regression relationship between SSY and the drainage area and factors in RUSLE due to sediment deposition in the lower reaches of the tributary. In the Jialing basin, the main factors for the occurrence of the positive relationship between SSY and the drainage area are the slope length and steepness factor LS and support practice factor P, and the positive relationship between SSY and the drainage area also keeps in the multiple regression between SSY and factors in RUSLE and the drainage area. There is not a significant regression relationship between SSY and the drainage area in the Wu-Chishui-Heng (Wujiang-Chishui-Hengjiang) basins due to intensive human activities.