|
|
|
| Analysis of the sediment reduction benefits of soil and water conservation measures and its influencing factors in Dali River Basin |
| Ran Dachuan1,2,3,Li Zhanbin2,Zhang Zhiping4,Li Peng2,Luo Quanhua4 |
| 1.Yellow River Institute of Hydraulic Research,Yellow River Conservancy Commission,450003,Zhengzhou;2.Xi'an University of
Technology,710048,Xi'an;3.State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,712100,Yangling,Shaanxi;4.Xifeng Soil and Water Conservation Experimental Station,Yellow River Conservancy Commission,745000,Qingyang,Gansu: China |
|
|
|
|
Abstract The relationship between sediment reduction benefit and preserved area and allocation rate of soil and water conservation measures and flood season rainfall as well as other influencing factors in Dali River Basin was studied.The relationship between sediment reduction of warping dams and sediment reduction of slope measures was analyzed also.The results showed that under the current condition of watershed management the sediment reduction benefit only reaches 9% by controlling measures on slope.The best maximum sediment reduction benefit can be reached when the allocation rate of terraced field,forested land,grasslands and warping dam land is 18.6∶73.2∶4.6∶3.6.The best allocation rate of warping dam land is 4% to reach the best sediment reduction benefit of soil and water conversation measures.The sediment reduction of soil and water conservation measures has close relation with flood season rainfall and shows positive correlation between them.Flood rainfall range from 300 mm to 500 mm can reach the best sediment reduction ability of soil and water conservation measures in Dali River Basin.During watershed management periods,the sediment reduction of slope measures is less than 6 million t/a and the sediment reduction of warping dam is less than 30 million t/a in the 2/3 of the total years.Since 1990's,the sediment reduction of measures on slope has close relation with sediment reduction of warping dam.The increase range of sediment reduction amount of warping dam is less than that of measures on slope.
|
|
Received: 10 September 2009
|
|
|
|
|
|
|
