Analysis of Function of Soil and Water Conservation and Ecological Project Construction in Flood and Sediment Reduction and Sustainable Development Strategy for the Middle Yellow River―Taking Huangfuchuan and Jinghe River Watersheds as an Example

摘要

According to Soil and Water Conservation Method study achievement of the 2nd water and sediment fund of Ministry of Water Resources, this paper analyzes the effect of reducing flood, sediment and erosion of soil and water conservation measure, especially warping dam, in He-long section of middle Yellow River, Jing River, Beiluo River and Wei River watersheds. The result indicates that soil and water conservation measure reduced annually flood 5.456 x 10~8m~3 and sediment 2.238 x 10~8t in He-Long section of middle Yellow River, Jing River, Beiluo River and Wei River watershed in 1970 ～ 1996. They respectively occupied 4.6% and 22.9% of annual total volume of water and sedimenl of the corresponding region. Due to sediment reduced by soil and water conservation measure, 4.5 x 10~9m~3 water for transporting sediment can be saved and reduced silt 1.57 x 10~8 t equal to 1.16 x 10~8m~3 in lower Yellow River every year. During 1970 ～ 1996, reduced silt amount to 3.13 x 10~9m~3. If the cost of clearing silt is two RMB per m~3, this will save cost of clearing silt 6.3 x 10~9yuan. The recent harnessing strategy of soil and water conservation and ecology project construction in Huangfuchuan watershed is: regarding to dam system construction in channel as cut-in point, channel dam system construction with harnessing channel mainstay project as primary is strengthened. Adjusting measures to local conditions, farmland receding forestry and grass and actively advances vegetation building. With fully exerting self-repair ability of ecology system, earthy - rocky area is harnessed by restraining entrance in large scale. In Jing River watershed, soil and water conservation sustainable development strategy is: Prevention and harness are paid same attention to. Slope and gully are comprehensively harnessed at the same time. In order to control expansion of soil and water erosion areas produced by human intervention, planting and protection of vegetation should be attached importance to and reinforce prevention and supervision. While slope and channel harness should be strengthened, especially channel dam system construction that take mainstay project and silt - trap dam as primary. Making comprehensive effect on blocking sediment and reducing erosion, conserving soil and water and improving ecology environment is coming true.