基于GAMLSS模型的资水流域最大日径流研究

Research on annual maximum daily runoff of Zishui River Basin Based on GAMLSS model

摘要

【目的】受全球气候变化和人类活动共同影响,资水流域极端气象水文事件日益增加,导致水文过程的一致性受到破坏,从而使得传统水文频率计算方法得到的计算结果存在不确定性。【方法】因此,基于资水流域桃江站1963—2022年水文气象资料,采用GAMLSS模型构建多协变量组合不同分布的非一致模型,综合比较各模型的拟合优度,选择最优模型计算不同设计频率下的年最大日径流设计值。【结果】结果表明,降水对径流变化的贡献率为66.52%,是导致资水流域年最大日径流序列上升的主要原因。此外,以降水、气温以及水库指数为协变量的GA分布模型拟合效果最优,可有效阐述降水变化和人类活动影响下资水流域年最大日径流的动态变化特征。【结论】随着城市发展资水流域的年最大日径流受到降水显著影响,洪涝威胁日趋增大,研究结果可为变化环境下资水流域水资源管理和水安全维护提供一定参考。

Abstract

[Objective] Due to the influence of global climate change and human activities, extreme meteorological and hydrological events in the Zishui Basin are increasing day by day, resulting in the destruction of the consistency of hydrological processes, which makes the calculation result obtained by traditional hydrological frequency calculation method uncertain. [Methods] Therefore, based on hydrological data and meteorological data of Taojiang Station in the Zishui Basin from 1963 to 2022, a non-consistent model with different distribution of multiple covariates was constructed using the GAMLSS model. The good degree of fit of each model was comprehensively compared, and the design value of annual maximum daily runoff under different design frequencies was calculated using the optimal model. [Results] It is shown by the result that the contribution rate of precipitation to runoff change is 66. 52%, which is identified as the main reason for the increase of annual maximum daily runoff series in the Zishui basin. In addition, the best fitting effect is shown by the GA distribution model with precipitation,temperature, and reservoir index as covariables, which can be used to effectively describe the dynamic change characteristics of the annual maximum daily runoff in the Zishui basin under the influence of changes in precipitation and human activities. [Conclusion] As the annual maximum daily runoff of the urban development watershed is significantly affected by precipitation,the flood threat is being increased, and some reference for water resources management and water security maintenance in the watershed under the changing environment can be provided by the research result.

关键词

GAMLSS模型 / 协变量 / 年最大日径流 / 气候变化 / 人类活动 / 降水 / 水文过程 / 极端降雨

Key words

GAMLSS model / covariate / annual maximum daily runoff / climate change / human activity / precipitation / hydrological processes / extreme rainfall

基金资助

国家自然科学基金项目(52079010)

湖南省自然科学基金项目(2022JJ40492)

湖南省研究生科研创新项目(CLSJCX23052)