Analysis of water and sediment changes and channel evolution in the lower Yellow River before and after the operation of the Xiaolangdi dam
Xiaolangdi Dam is a key water conservancy project for the governance and development of the Yellow River,playing an important role in reducing sedimentation in the downstream channel of the dam and forming a stable medium water channel.This paper takes a typical downstream section of the Xiaolangdi Reservoir as a case study,and uses the single factor variance method and coefficient of variation to analyze the changes in the downstream water and sediment regime and channel morphology before and after the operation of the dam.The main conclusions are as follows:After the operation of the Xiaolangdi Dam,the inter-annual runoff changes at Huayuankou and Jiahetan hydrological stations were smaller than before the dam operation,showing an overall upward trend.The annual average sediment concentration significantly decreased,and the inter-annual changes were relatively small.The monthly average runoff at Huayuankou varies most significantly in June and August,with the high monthly average sediment concentration changing from July to September before the dam operation to May,July,and August after the dam operation.From 2006 to 2018,the annual erosion amount of the Xixiayuan to Jiahetan section of the Yellow River accounted for half of the total erosion amount in the lower reaches of the Yellow River.The cross-section of the Huayuankou river developed from a wide and shallow shape to a narrow and deep direction.
Xiaolangdi damwater and sediment regulationriver channel morphologylower Yellow River
NETL
NSTL
万方数据
维普
