1958-2022年黄河头道拐水文站水沙特征分析及预测

Analysis and Prediction of Runoff and Sediment Flux Characteristics at the Toudaoguai Hydrological Station of the Yellow River from 1958 to 2022

[目的]探究黄河头道拐水文站径流量与输沙量演变特征,为区域水资源合理规划提供理论依据。[方法]基于1958—2022年径流输沙数据,采用非参数检验方法与CEEMDAN法研究了头道拐水文站水沙趋势、突变及周期变化特征,并通过水沙月值数据构建Informer预测模型。[结果](1)年径流量与年输沙量的M-K统计量分别为-3.380,-5.067。年径流量和年输沙量分别于1986年、1968年和1986年发生突变,下降率分别为36%,44.38%和61.32%。(2)使用CEEMDAN法对径流量与输沙量年值序列进行分解后均得到3个IMF分量与1个RES分量,水沙序列的3个IMF分量平均周期分别为3.69 a,7.67 a,30 a和3.41 a,7.5 a,26 a;水沙月值序列经过分解后得到7个IMF分量,短周期为3.46月与3.61月,长周期为226.33月与184.50月,主导周期为7.25月和8.09月。(3)模型构建后发现径流的预测精度高于输沙,原因是输沙量受影响因素众多,变动幅度更大,较径流量预测难度大。[结论]黄河头道拐水文站水沙存在显著下降趋势,主要归因于降水影响,且序列突变节点与上游水库建成密切相关。

[Objective]The aims of this study are to explore the evolution characteristics of runoff and sediment flux at the Toudaoguai hydrology station of the Yellow River,and to provide theoretical basis for rational planning of regional water resources.[Methods]Based on the runoff and sediment flux data from 1958 to 2022,non-parametric testing methods and the CEEMDAN method were adopted to study the trends,abrupt changes,and periodic variations in runoff and sediment flux at the Toudaoguai hydrological station.Furthermore,an Informer prediction model was constructed by using monthly runoff and sediment flux data.[Results](1)The M-K statistics for annual runoff and annual sediment flux are-3.380 and-5.067,respectively.The annual runoff and sediment flux experienced abrupt changes in 1986,1968 and 1986,with decline rates of 36%,44.38% and 61.32%,respectively.(2)After decomposing the annual runoff and sediment flux sequences using the CEEMDAN method,three IMF components and one RES component were obtained for both sequences.The average periods of the three IMF components in the runoff and sediment flux sequences were 3.69 years,7.67 years,30 years and 3.41 years,7.5 years,26 years,respectively.The decomposition of the monthly runoff and sediment flux yielded 7 IMF components,with short periods of 3.46 months and 3.61 months,long periods of 226.33 months and 184.50 months,and dominant periods of 7.25 months and 8.09 months.(3)After constructing the model,it was found that the prediction accuracy for runoff was higher than that for sediment flux.This is because that sediment flux is influenced by numerous factors and exhibits a more extensive range of variation,making it more challenging to predict than runoff.[Conclusion]There is a significant downward trend in runoff and sediment flux at the Yellow River Toudaoguai hydrological station,which is mainly attributed to the influence of precipitation,and the abrupt change points in the sequences closely related to the construction of upstream reservoirs.