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黄河内蒙古河段冲淤演变及其影响因素(英文) 总被引：5，自引：2，他引：3
Rivers with fluvial equilibrium are characterized by bed deformation adjustment. The erosion-deposition area in cross-section reflects this characteristic, which is a base of researching the river scour and deposition evolution by time series analysis. With an erosion-deposition area indicator method proposed in this paper, the time series of erosion-deposition area quantity at Bygl and Shhk stations were obtained with the series duration of 31 years from 1976 to 2006. After analysis of its trend and mutation, three different ten- dencies about the evolution were observed in general from the quasi-equilibrium phase through a rapid shrinkage to the final new quasi-equilibrium. It is also found that the trend of erosion-deposition area series will change once a big flood occurred in some of the tributaries, and its ever greater influence is due to the decrease of deluge with the completion of upstream reservoirs. Almost all the turning points were coincident with the time when hyper-concentrated sediment flood occurred in some tributaries. With the time series of clear mutations since the late 1990s, the Inner Mongolian Reach has been in a new equilibrium phase. This can be concluded in two aspects. 1. The absence of big floods and sediment transportation from tributaries result in the river shrinkage, and to regain the channel flow-carrying capacity in Inner Mongolian Reach a large flood is needed both of high peak discharge and of lengthy interval to destroy the new equilibrium. 2. The proposed method of erosion-deposition area indicator is of great help to channel scoureposition evolution analysis because it can demonstrate real time deformation of cross section in quantity. 相似文献
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黄河内蒙古河段冲淤演变及其影响因素 总被引：6，自引：1，他引：5
冲淤平衡的河流具有调整河床变形使之趋向不变形的特性,这种特性必然反映在河床横断面冲淤演变的趋势之中。据此,采用横断面冲淤指标跟踪计算法生成黄河上游巴彦高勒、三湖河口站1976-2006 年的横断面冲淤演变时间序列,对该长期序列的趋势变化和突变特点进行分析后发现：内蒙古河床演变明显存在3 个阶段,即演变相对稳定阶段、河床快速萎缩变形阶段和新的相对稳定阶段,以及孔兑来沙大的年份是横断面冲淤面积趋势改变的时间。大型水库修建后,孔兑来沙对河道横断面冲淤趋势变化的影响更加显著,表明近年来大洪水缺失和孔兑来沙的共同作用是导致河床萎缩的重要根源。90 年代中后期横断面冲淤演变再次发生突变之后,内蒙河段进入到一个新的相对稳定期,河床边界条件已经和来水来沙条件相适应,因此在新的稳定条件下,如何治理内蒙河道的淤积萎缩值得探讨。 相似文献
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