基于指标筛选的汛期时间域划分及合理性分析

Determining Flood Season Based on Index Screening and Rationality Analysis of Division Results

针对以往分期指标冗余、信息量小、季节性差,采用不同划分结果比较来进行合理性分析的不足,研究基于指标筛选的汛期时间域划分及合理性分析.本文提出基于"独立性、信息性和季节性"的指标筛选方法,根据筛选后的分期指标,应用Fisher最优分割法原理,进行汛期时间域划分;采用改进的Cunderlik法对本方法与其他方法的最终划分结果进行合理性分析.以山西省汾河二库控制流域为例,进行模型验证,确定汛期时间域为5月1日~10月15日.改进的Cunderlik法分析结果表明:与其他划分方法相比,文中方法更为合理可信,可以为我国流域汛期时间域划分及合理性分析提供一定参考依据,以期为分期指标选取提供支撑.

Previous studies had some shortcomings,such as indicator redundancy,less information,poor seasonality,and comparing different division results for rationality analysis. In order to overcome these defects,a study on determining flood season based on index screening and its rationality analysis was carried out. Based on"independence,informativity and seasonality",the index screening method was proposed. According to staged indicators after screening,Fisher’s optimal segmentation method was used to determining flood season. The rationality of the final division results of this method and other methods was analyzed by the improved Cunderlik method. Taking watershed controlled by the Fenhe River Reservoir II in Shanxi Province as an example,the model was verified,determining flood season from May 1st to October 15th.Analysis results from improved Cunderlik method show that compared with other methods,proposed method in this paper is more reasonable and credible,which can provide reference for determining flood season of our country’s watershed and its’ rationality analysis,so as to provide support for the selection of staging indicators.