摘要
河流流量多通过水文观测站获取,但受复杂地形、恶劣气候等因素限制,许多地区缺少相关水文观测数据。多站水力几何(AMHG)法仅根据河流宽度的时空变化即可计算出流量,在本质上扩展了传统的单站水力几何(AHG)法。该文以典型水文资料缺失地区黄河源区为研究对象,在GEE平台上基于Landsat8和Sentinel-2影像提取河道掩膜,采用RivWidth_v04工具自动提取不同时相影像的河流宽度,分析AMHG方法在研究区的适用性和模拟精度。结果表明:1)应用RivWidth_v04提取河流宽度精度较高,使用高分辨率遥感影像可降低河宽误差;2)2015-2021年玛曲、军功河段AMHG-Landsat模拟值与实测值的纳什效率系数(NSE)分别为0.75和0.67,均方根误差(RMSE)分别为155.66 m^(3)/s和225.15 m^(3)/s,相对均方根误差(RRMSE)分别为34.04%和38.86%,模拟结果均较好;3)结合高分辨率Sentinel-2影像可以增加河流流量的估算频次,更好地反映研究河段的水文过程,提高AMHG方法在河流监测和水资源管理领域的实用性;4)最小和最大流量限制对AMHG方法模拟结果有很大影响。
River discharge is one of the key parameters of water cycle.Due to the limitations of complex terrain,severe weather conditions,etc.,many regions in the world lack relevant hydrological observation data.The development of remote sensing technology provides new technical means for river runoff monitoring.Among them,the at-many-stations hydraulic geometry(AMHG)method can estimate the river discharge only through the temporal and spatial variation of river width,enables river discharge estimation using solely remote sensing data.This method essentially extends the traditional at-a-station hydraulic geometry(AHG)and lays the foundation for space monitoring stations.Taking the source region of the Yellow River,a typical data-deficient region,as the study area,this paper extracted river masks from Landsat8 and Sentinel-2 images in different phases on GEE platform,used the software tool RivWidth_v04 automatically measure the river width,and analyzed the applicability and estimation accuracy of AMHG.The results show that:1)The accuracy of river width extracted by RivWidth_v04 is relatively high,and the remote sensing image with high spatial resolution could reduce the error of river width.2)The NSE coefficients of the estimated discharge based on AMHG-Landsat and the measured values are 0.75 and 0.67,RMSE are 155.66 m^(3)/s and 225.15 m^(3)/s,and RRMSE are 34.04%and 38.86%,respectively,in the Maqu and Jungong reaches from 2015 to 2021,with good estimation results.3)Combined with Sentinel-2 images with high temporal resolution,the estimation frequency of river discharge is supplemented to better reflect the hydrological process of the studied reaches and improve the availability of AMHG method in river monitoring and water resources management.4)Minimum and maximum discharge constraints have great impact on discharge estimation based on AMHG.
作者
白娟
张亦弛
甘甫平
郭艺
闫柏琨
杨胜天
李和谋
邢乃琛
马燕妮
刘琪
BAI Juan;ZHANG Yi-chi;GAN Fu-ping;GUO Yi;YAN Bo-kun;YANG Sheng-tian;LI He-mou;XING Nai-chen;MA Yan-ni;LIU Qi(China Aerospace Geophysical and Remote Sensing Center for Natural Resources,Beijing 100083;Faculty of Geographical Science,Beijing Normal University,Beijing 100875;College of Water Sciences,Beijing Normal University,Beijing 100875,China)
出处
《地理与地理信息科学》
CSCD
北大核心
2023年第1期15-22,共8页
Geography and Geo-Information Science
基金
自然资源部航空地球物理与遥感地质重点实验室课题(2020YFL22)
高分专项(民用)项目“高分航空载荷自然资源调查应用示范”(04-H30G01-9001-20/22-01-08)。
