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| Effects of the control measures closing to nature on slope gradient of relative balance for river bank: A case study of the Taohua River in Changshou District, Chongqing City |
| Zhu Weili，Wang Yunqi，Lei Shengkun |
| College of Soil and Water Conservation，Beijing Forestry University，Key Laboratory of Soil & Water Conservation and Desertification Combating of Ministry of Education, 100083， Beijng，China |
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Abstract According to the site conditions of Taohua River, Chongqing City, taken bare bank as control, three control measures closing to nature, including natural prototype revetment, revetment mat fabric of natural materials and flat bag geotextile revetment, were selected to protect river bank. After two years of natural restoration, the effects of three measures on the stability of river bank were analyzed from: the equation of sediment moving, and soil shear-resistance strength. Results show that 1) the gradient of relative balance derived from the sediment moving equation was given as follows: natural prototype revetment (>34.9°), revetment mat fabric of natural materials (>33.3°), flat bag geotextile revetment (>32.3°), and bare bank (>25.5°). 2) The gradient of relative balance derived from soil shear-resistance strength was natural prototype revetment (35.0°), revetment mat fabric of natural materials (26.2°), flat bag geotextile revetment (30.3°), bare bank (19.9°). 3) The slope gradient of relative balance derived from the equation of sediment moving were greater than that from the soil shear-resistance equation, therefore, it can be concluded that the gravity erosion occurred more possible than water erosion. Based on the values from soil shear-resistance equation in this paper, it can be concluded that compared with bare bank, the slope gradient of relative balance could be improved by 10.4°, 6.3°, 15.1° respectively by natural prototype revetment, revetment mat fabric of natural materials and flat bag geotextile revetment.
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Received: 27 September 2011
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