In this study, we analyzed changes in the water and sediment properties in the Yellow River during the flood season, which is the period with the largest runoff yield and sediment load in this river. The aim of this study was to understand the impact of water and soil conservation measures during this crucial season, and we focused on the Huangfuchuan drainage basin as the study region. We analyzed factors including the precipitation, runoff and sediment yield, and suspended sediment grain-size distribution during each of the flood seasons in 1986 to 1990 (P1) and 2006 to 2010 (P2). The results showed that most of the precipitation during the flood season was concentrated in the southeastern part of the basin. The mean flood season precipitation was similar in the two periods, with 260.1 mm and 256.9 mm in P1 and P2, respectively, but the frequency of floods in the basin decreased by 59.4% during P2. Compared with P1, the mean flood volume, sediment load, and duration during P2 decreased by 52.17%, 68.57%, and 1.52%, respectively. The composition of the sediments in the Huangfuchuan drainage basin was dominated by the presence of silts, which represented 61.2% and 96.6% of the total sediments in P1 and P2, respectively. The results obtained in this study demonstrate that the water and sediment conditions in the Huangfuchuan drainage basin during the flood season have improved over time, with a more homogeneous suspended sediment composition, more concentrated water and sediment processes, and decreases in the flood frequency, volume, and sediment transport. Our results indicate the effectiveness of river basin regulation, and they may be used as a reference for treatment of the main sediment production areas in the Yellow River.

中文翻译：

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水土保持工程后皇甫川河径流泥沙负荷变化

在这项研究中，我们分析了黄河在汛期水沙性质的变化，这是黄河产水量和泥沙负荷最大的时期。本研究的目的是了解水土保持措施在这个关键季节的影响，我们将皇甫川流域作为研究区域。分析了1986~1990年（P1）和2006~2010年（P2）各汛期降水量、产流产沙量、悬浮泥沙粒度分布等因素。结果表明，汛期大部分降水集中在流域东南部。两个时期的平均汛期降水量相似，P1 和 P2 分别为 260.1 毫米和 256.9 毫米，但流域内洪水频率在P2期间下降了59.4%。与P1相比，P2期间的平均洪水量、泥沙量和持续时间分别减少了52.17%、68.57%和1.52%。皇甫川​​流域沉积物成分以粉砂为主，分别占P1和P2总沉积物的61.2%和96.6%。本研究结果表明，汛期皇甫川流域水沙状况随时间推移有所改善，悬浮泥沙成分更加均匀，水沙过程更加集中，洪水频率、洪水量减少。 , 和泥沙输送。我们的结果表明流域调节的有效性，