黄河刁口废弃流路冲淤演化及其影响因素

Erosion and deposition evolution of the abandoned Diaokou course of the Yellow River and influential factors

刁口流路是黄河1964年至1976年期间的行水流路,在1976年黄河人为改道清水沟后废弃,在1992年将其作为备用流路。依据不同年份刁口废弃流路的高程测量数据,计算了不同时期刁口废弃流路的冲淤量,分析了刁口废弃流路不同时段的冲淤变化特征,探讨了刁口废弃流路冲淤变化的受控机制。研究结果表明,1976−2000年,刁口废弃流路河道整体处于冲刷状态,冲刷速率约为1.92×10^(6)t/a;2000−2016年,河道整体处于淤积状态,淤积速率约为7.99×10^(6)t/a。刁口废弃河道的冲淤在空间上存在明显的差异,2000−2016年,以断面D20为分界线,向海一侧的河段呈现冲刷状态,河道槽蓄量增加;而向陆一侧的河段呈现淤积状态,河道槽蓄量减少。废弃河道的冲淤演化除受生态调水、海洋动力侵蚀等影响外,更多地受到河道周边油田开发以及两岸的农田和林业发展等因素的影响。因此,从维持河道行水能力的角度来看,亟需对河道开展维护修缮,以保证刁口流路作为黄河入海备用流路的适宜性。

From 1964 to 1976,the Yellow River flowed through the Diaokou course into the Bohai Sea.In 1976,the Diaokou course was abandoned and replaced by an artificial diversion to the Qingshuigou course.Based on the measured elevation data of the abandoned Diaokou course in years of 1976,2000,and 2016,we calculated the volume of erosion and deposition along the Diaokou course at different stages,described the spatial distribution of erosion and deposition of the Diaokou course,and discussed the potential impact factors on the Diaokou course evolution over the last 40 years after its abandonment.The results indicate that during 1976-2000,the Diaokou course experienced erosion at rate of~1.92×10^(6) t/a,and during 2000-2016,the Diaokou course was silted at deposition rate of~7.99×10^(6) t/a.The erosion and deposition along the Diaokou course present significant spatial difference during 2000-2016.Taking section D20 as the boundary,the seaward river section was in scouring state,and the storage capacity of river channel increased;while the landward section was in siltation state,and the storage capacity of the river channel decrease.The evolution of erosion and sedimentation in the Diaokou course was not only affected by the ecological water diversion and marine dynamic erosion,but also by the development of nearby oil fields,farming,and forestation.Therefore,to maintain the water flow capacity of the Diaokou course,cleaning up the Diaokou course is urgent to ensure good condition of the Diaokou course as a backup waterway of the Yellow River seaward empting.