摘要
【目的】降低水文地理数据对水文模型中径流模拟的影响。【方法】本文以90m分辨率的MERITDEM为基础,运用GIS信息系统软件和Python程序的自动校正等手段生成了1套洞庭湖水系范围内的水文地理数据集(流向、汇流累积量、河网、流域面积、河长和流域分区)。通过河网可视化分析,流域面积及河流长度对比和水文模型检验等方法综合评估了新数据集的质量。【结果】与HydroSHEDS数据集相比,新生成的MERIT河网数据集在流域面积上与之差别不大,但在DEM高程、流向分布、河网结构和河长的计算方面,2套数据集(MERIT和HydroSHEDS)却存在着较大的差异。水文模型的结果显示MERIT数据集的日纳什系数和月纳什系数分别为0.41和0.52,均好于HydroSHEDS。【结论】MERIT提取的河网能够更加真实的反应研究区域的河道位置,保证其他水文汇流参数(如河流长度、流域分区等)的计算,降低水文模拟中的参数不确定性,对下一步的洪水预报研究工作提供了强有力的数据支撑。
【Objective】High-resolution hydrographic datasets have become increasingly accessible which will have a significant impact on hydrological modelling such as runoff and flood inundation.In this paper,we present a new hydrographic dataset.【Method】The new raster hydrographic map,including flow direction and accumulation,drainage areas and flow distance,was developed using GIS and python programs for the Dongting River Basin,based on the latest multi-error-removed improved-terrain digital elevation model(MERIT DEM).It shows a robust performance in visual inspection,basin area,flow distance and model evaluation.The quality of the dataset was comprehensively evaluated using methods such as river network visualization analysis,comparison of basin area and river length,and hydrological modeling.【Result】The new hydrographic databases developed from the latest MERIT DEM show great difference in flow direction,river network structure and river length from those derived from the traditional databases,HydroSHEDS.The results obtained from the associated hydrological model indicate that daily and monthly Nash coefficients calculated from the new dataset are 0.41 and 0.52,respectively,better than those calculated from HydroSHEDS.【Conclusion】The newly developed hydrographic dataset provides a more accurate representation of the locations of the rivers,thereby reducing the uncertainties in predicting runoffs and potential flooding.This dataset is now available for academic research and educational use.
作者
黄泽群
廖春花
陈玉贵
陈唯天
赵恩榕
罗红梅
谢睿恒
HUANG Zequn;LIAO Chunhua;CHEN Yugui;CHEN Weitian;ZHAO Enrong;LUO Hongmei;XIE Ruiheng(Hunan Meteorological Service Center,Changsha 410118,China;Key Laboratory for Meteorological Prevention and Mitigation of Disasters in Hunan Province,Changsha 410118,China;School of Atmospheric Science,Sun Yat-sen University,Zhuhai 519082,China;Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies,Guangzhou 510275,China;Hunan Meteorological Observatory,Changsha 410118,China)
出处
《灌溉排水学报》
CAS
CSCD
北大核心
2023年第6期67-73,80,共8页
Journal of Irrigation and Drainage
基金
湖南省气象局重点专项(CXFZ2023-ZDZX06)
湖南省气象局第三期业务能力建设项目(NLJS09)。
关键词
数字高程模型
流向
河网
流域划分
水文气象服务
DEM
flow direction
river network
basin delineation
hydrometeorological services
