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Traditional control measures of soil erosion and their environmental effects on flow and sediment in the water source area of Beijing and Tianjin |
Zhao Ting1,2, Xie Yongsheng1,3, Jiang Qinglong3, Zhang Huai4, Zhou Wei4 |
1.Institute of Soil and Water Conservation, Chinese Academy of Sciences and the Ministry of Water Resources, 712100,Yangling,Shaanxi; 2.Graduate University of the Chinese Academy of Sciences, 100049, Beijing; 3.College of Resources and Environment, Northwest A&F University, 712100,Yangling,Shaanxi;4.Institute of Soil and Water Conservation of Chengde City, 067000,Chengde, Hebei: China |
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Abstract The traditional guiding ideology and treatment on soil erosion control pay attention to ecological and economic benefits of the harnessing area,which will reduce the sediment yield. However, the reduction of sediment could lead to the decrease of water, which will aggravate the water contradiction between upstream and downstream in the water source areas of Beijing and Tianjin. Environmental effects of slope measures on water and sediment were studied by investigation and location experiment in Dadai Watershed locating in Fengning County, Chengde City. Results showed that the erosion modulus in slope farmland and artificial grassland substantially exceeded soil loss tolerance in rocky mountain areas of northern China. Natural meadow had higher annual runoff and runoff coefficient than arbor forests and shrub forests. Traditional fish-scale pits measures had significant effects on sediment trapping and reduction of water yield. For moderate and mild degraded grassland under the management of closing hills, the vegetation coverage could improve by 2.84% and 1.97% in shady slope and sunny slope per year. Some traditional measures like fish-scale pits should be limited in areas where occurred serious soil erosion,and their preparation standard should be degraded. Large areas of moderate and mild degraded grassland under the management of closing hills could not only reduce sediment yield,recover vegetation,but also increase runoff.
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Received: 11 April 2011
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