土地利用驱动的少资料流域分布式水文模型参数区域化方法:以跨境湄公河流域为例

Land use-driven parameter regionalization for distributed hydrological modeling in data-scarce basins: A case study of Mekong River Basin

摘要

【目的】针对跨国水利工程中少资料地区水文模拟长期面临的参数识别难题,提出一种基于土地利用类型的栅格分布式水文模型参数移植方法。【方法】以土地利用类型为基本单元,构建“土地利用-参数”映射关系,形成结构化参数查找表,突破传统参数区域化对测站密度的依赖,实现参数在相似下垫面条件下的跨流域稳健迁移。选取湄公河流域柬埔寨段作为案例,通过参证流域分区率定建立地类-参数对应表,并迁移至目标流域进行验证。【结果】结果表明:模型在参证流域(磅湛站)率定期与检验期的纳什效率系数(NSE)分别为0.87和0.86,径流总量相对误差(RE)分别为5.71%与8.61%;参数迁移至目标流域后,达萨河Thnous Loung站的NSE达0.87、 RE为8.37%,斯伦河Kralanh站的NSE为0.89、 RE为7.01%,其精度显著高于瞬时单位线法(NSE分别为0.76和0.68)和前期影响雨量法(NSE分别为0.32和0.74),在洪峰过程模拟与水量平衡方面均表现出更优的适用性。【结论】所提出的方法通过土地利用载体实现了参数的有物理依据的跨流域迁移,填补了缺资料地区的水文模型参数的不足,为分布式水文模型过程模拟方面提供了有效参考。

Abstract

[Objective] To address the long-standing challenge of parameter identification in hydrological modeling for data-scarce regions within transnational water conservancy projects, a parameter transfer method for a raster-based distributed hydrological model based on land use types is proposed. [Methods] Using land use types as basic units, a “land use-parameter” mapping relationship was constructed to form a structured parameter lookup table. This approach overcame the dependence of traditional parameter regionalization on gauging station density, enabling robust cross-basin parameter transfer under similar underlying surface conditions. The Cambodian section of the Mekong River Basin was selected as a case study. A land use type-parameter lookup table was established through zonal calibration in a reference river basin, which was then transferred to the target river basin for validation. [Results] In the reference river basin(Kompong Cham station), the Nash-Sutcliffe efficiency(NSE) values during the calibration and validation periods were 0. 87 and 0. 86, respectively, with relative errors(RE) in total runoff volume of 5. 71% and 8. 61%. After the parameters were transferred to the target river basin, the NSE reached 0. 87 at the Thnous Loung station on the Das River with an RE of 8. 37%, and the NSE was 0. 89 at the Kralanh station on the Sreng River with an RE of 7. 01%. The accuracy was significantly higher than that of the instantaneous unit hydrograph method(NSE of 0. 76 and 0. 68) and the antecedent precipitation index method(NSE of 0. 32 and 0. 74), demonstrating superior capability in simulating flood peak processes and maintaining water balance. [Conclusion] The proposed method realizes physically based cross-basin parameter transfer using land use as a carrier, fills the gap in hydrological model parameters in data-scarce regions, and provides an effective reference for process simulation in distributed hydrological modeling.

关键词

参数区域化 / 无资料流域 / 土地利用均质性 / 分布式水文模型 / 数据稀缺地区 / 水文非平稳性 / 湄公河流域 / 气候变化

Key words

parameter regionalization / ungauged basins / land use homogeneity / distributed hydrological model / data-scarce regions / hydrological non-stationarity / Mekong River Basin / climate change

基金资助

国家重点研发计划(2023YFC3006605)

中交长江建设发展集团有限公司课题(CJRD-2024-1-04)

重庆市水利科技项目(CQSLK-2023009)

重庆市水利科技项目(CQSLK-2022005)

重庆市水利科技项目(CQSLK-2022011)

广西科技计划项目资助(桂科AA23062023)