摘要
变化环境下流域水文物理特性常呈现"非稳态"特征,代表流域特性的模型参数也会随之发生变化,因此,开展水文模型参数时变研究有助于提高水文模拟精度。考虑植被条件和人类活动对水文过程的影响,基于植被归一化指数、人口、地区生产总值、粮食产量和有效灌溉面积5个指标建立两参数月水量平衡模型参数的时变函数表达式,并考虑4种参数时变情形。选取直门达、张家山、咸阳、横江、丹江口和峡江站6个水文站分析对比4种情形下模型的径流模拟结果及其不确定性。结果表明:所有站点在1982—2006年内水文物理特性呈现"非稳态"特征;且较常参数而言,时变参数模型模拟效果更好,并获得更优的确定性预报结果,其中直门达站径流模拟精度提高最为显著,率定期和检验期内的纳西效率系数(NS)分别提高了10. 3%和8. 8%。该研究可以为变化环境下流域水库调度、水资源规划与管理等提供理论依据和技术支撑。
The non-stationary nature of watersheds due to changing environments has invalidated the assumption that hydrological model parameters reflecting the physical characteristics of watersheds were time-invariant.To improve the performance of a hydrological model,it is thus necessary to consider the time variation of the model parameters.In this paper,the linear and nonlinear functions of five environment-related indicators（Normalized Difference Vegetation Index,population,gross domestic production,grain production,and irrigated area） were employed to describe the temporal variation of the parameters of the two-parameter monthly water balance model to reflect the impacts of vegetation change and human activities on hydrological processes.Impacts of four different scenarios of the temporal variation of two parameters were investigated for the upstream catchments of six hydrological stations,i.e.,Zhimenda,Zhangjiashan,Xianyang,Hengjiang,Danjiangkou,and Xiajiang,by comparing the model performances under different scenarios.Results showed that the hydro-meteorological characteristics of the study catchments was non-stationary during the period 1982—2006.Compared with the baseline scenario with all time-invariant parameters,the model with time-varying parameters could improve the monthly runoff simulations and provide more skillful predictions.Specifically,the Nash-Sutcliffe efficiency coefficient（NS） of the model with time-varying parameters improved by 10.3% and 8.8% in the calibration and validation periods,respectively,at the Zhimenda hydrological station.This research can provide the theoretical basis and technical support for reservoir operation and water resources planning and management.
作者
熊立华
刘烁楠
熊斌
许文涛
XIONG Lihua;LIU Shuonan;XIONG Bin;XU Wentao(State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,China)
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2018年第5期625-635,共11页
Advances in Water Science
基金
国家重点研发计划资助项目(2017YFC0405901)
国家自然科学基金资助项目(51525902)~~
关键词
变化环境
两参数月水量平衡模型
时变参数
NDVI
人类活动
changing environment
two-parameter monthly water balance model
time-varying parameters
Normal-ized Difference Vegetation Index
human activities
