Effects of hedgerows on sediment erosion in Three Gorges Dam Area,China  

作　　者：Chong-Feng BU Qiang-Guo OAI Sai-Leung NG Kwai-Cheong CHAU Shu-Wen DING 

机构地区：[1]Ph.D, Assistant Researcher, Institute of Soil and Water Conservation, Northwest A＆F University, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, Shaanxi, China [2]Prof., Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China [3]Prof., Department of Geography and Resource Management, the Chinese University of Hong Kong, Hong Kong, China [4]Prof., Department of Resource and Environment, Huazhong Agricultural University, Wuhan 430070, China

出　　处：《International Journal of Sediment Research》2008年第2期119-129,共11页国际泥沙研究（英文版）

基　　金：The NSFC(National Natural Science Foundation of China,40701096);the Startup Fund of Northwest A&F University for Talented Scholars and Hong Kong Research Grants Council(4217/02H)provided funding for this research.

摘　　要：The Three Gorges Dam Area refers to the river section from Chongqing to Yichang on the Yangtze River, which has a drainage area of 75,098 km^2, and involves 19 cities and counties. Contour hedgerows have been used in this area to control soil erosion and to improve hillslope stability in the catchment of this river section. Five experimental hedgerow plots were established in 1994 in order to study the effects of hedgerows on erosion control. During the period of 1994-1997, runoff and soil loss data were collected on these test plots, including the chemical and physical properties of soil and related topographical data. The results indicate that： （1） after 4 years of cultivation and crop planting, soil fertility increased dramatically in the hedgerow plots. Soil organic matter, total nitrogen, and total phosphorus contents in the hedgerow plots were 5-9 times higher than that in the control plot. In each of the hedgerow plots, soil structure became more stable, the quantity of granules larger than 0.02 mm increased and those finer than 0.02 mm decreased; （2） All hedgerow plots showed a major effect on reducing soil loss and surface runoff; （3） Overland flow velocity along the upper portion of the hedgerow plots was greatly reduced due to hedgerow resistance, which explains the significant decrease in soil losses in hedgerow plots, despite the fact that the hedgerow plots and the control plots had the same total runoff.The Three Gorges Dam Area refers to the river section from Chongqing to Yichang on the Yangtze River, which has a drainage area of 75,098 km^2, and involves 19 cities and counties. Contour hedgerows have been used in this area to control soil erosion and to improve hillslope stability in the catchment of this river section. Five experimental hedgerow plots were established in 1994 in order to study the effects of hedgerows on erosion control. During the period of 1994-1997, runoff and soil loss data were collected on these test plots, including the chemical and physical properties of soil and related topographical data. The results indicate that： （1） after 4 years of cultivation and crop planting, soil fertility increased dramatically in the hedgerow plots. Soil organic matter, total nitrogen, and total phosphorus contents in the hedgerow plots were 5-9 times higher than that in the control plot. In each of the hedgerow plots, soil structure became more stable, the quantity of granules larger than 0.02 mm increased and those finer than 0.02 mm decreased; （2） All hedgerow plots showed a major effect on reducing soil loss and surface runoff; （3） Overland flow velocity along the upper portion of the hedgerow plots was greatly reduced due to hedgerow resistance, which explains the significant decrease in soil losses in hedgerow plots, despite the fact that the hedgerow plots and the control plots had the same total runoff.

关 键 词：HEDGEROW EROSION RUNOFF Soil properties Three Gorges Dam Project 

分 类 号：TV697[水利工程—水利水电工程]