水利水电技术（中英文）

"黄河流域治理,重在保护,要在治理"。明晰黄土高原生态治理成效及其影响下的黄河水沙关系变化,有助于为黄河水沙关系协调提供科技支撑。通过梳理黄土高原水土流失治理历程及措施变化,辨析了治理措施的减沙效应。研究表明:(1)黄土高原历经五个典型治理阶段,主色调由黄变绿,下垫面发生不可逆的变化;(2)2000年以来,主要产沙区汛期雨量偏丰且极端降雨增加,而黄河沙量相对1919—1959年锐减了85%,中游中常洪水发生频次降低,下游河道由淤积转为冲刷;(3)林草、梯田和淤地坝减沙成效显著,溃损淤地坝淤积泥沙出库比<15%,难以发生"零存整取"现象;(4)与历史极端降雨事件相比,2000年后相似降雨条件下,典型流域次洪水量和沙量分别减少30%～78%、53%～88%,水土保持成效显著;(5)新水沙情势下应适时调整黄土高原水土流失治理格局,并完善水沙调控体系,改造下游河道,解放滩区。

"The Yellow River governance focuses on protection and governance". Clarifying the effects of ecological governance on the Loess Plateau and its influences on variation of the runoff-sediment relationship of the Yellow River is helpful to provide a scientific and technical support for the coordinating the runoff-sediment relationship of the Yellow River. Through sorting out the processes of soil erosion control of the Loess Plateau and the changes of the governance measures, the sediment reduction effect of the governance measure are discriminated and analyzed herein. The study shows that(1)the Loess Plateau experiences five ty-pical governance processes and the dominant hue of the Loess Plateau changes from yellow to green, while the underlying surface therein is irreversibly changed;(2)since 2000, the rainfalls during flood seasonsare relatively abundant along with the increases of extreme rainfalls, while the sediment transport of the Yellow River is sharply decreased by 85% if it is compared with that du-ring the period of 1919—1959 along with the decreases of the occurrence frequencies of the middle stream moderate and normal floods and the transformation of the downstream channel sedimentation into erosion;(3)the sediment reduction effects from grass-land, terraced fields and warp-land dams are significant along with the sediment discharge ratio of less than 15%, thus the phenomenon of the so called"deposit in installments while withdraw in lump sum"is difficult to occur;(4)comparing with the historical extreme rainfall events, the typical secondary flood volumes and sediment yields within the river basin are decreased by 30%～78% and 53%～88% respectively with significant soil and water conservation effects under the conditions of the similar rainfalls and the intensities after 2000;(5)it is advisable to adjust the patterns of the soil erosion governanceof the Loess Plateau, perfect the water-sediment regulation system, improve the downstream channel and emancipate the flood plain under the new situation of water-sediment regime therein.