Cause analysis of the centennial trend and recent fluctuation of the Yellow River sediment load
摘要
The trend of the Yellow River sediment load in future is related to the development of the river basin management strategy in the new era. It has great significance to clarify the sediment load feature for the determination of future trend, especially under the typical and extreme precipitation. The study emphases on the sediment load fluctuation in the typical large sediment discharge years in 2013 and 2018, and the typical extreme heavy precipitation in 2017, based on analyzing the character and future trend of the sediment load. The result showed that the sediment load discharge decreased extremely in a stage style on century scales from 1919 to 2018, particularly those decreased to 244 million tons after 2000. The sediment load discharge from the Toudaoguai to the Tongguan region decreased 82% than that from the similar upstream rivers years, and the flood discharge decreased around 50%—85% from each extreme precipitation, along with the improvement of the erosion environment in the Loess Plateau. The typical extreme heavy precipitation did not generate the large sediment discharge in 2017 which confirmed that the ecological construction of soil and water conservation played a great significance for reducing sediment into the Yellow River. The fluctuation of the Yellow River sediment load is affected by the deposition from the waterways and the release from the reservoirs by the results of sediment source in 2013 and 2018 in the new era.