基于遥感和通量观测的实际蒸散发时空变化特征
Spatiotemporal variation characteristics of actual evapotranspiration based on remote sensing and flux observations:case study in the water conservation area of the Yellow River basin
鞠琴 1刘小妮 1刘娣 1申同庆 1谷黄河 1王国庆 2余钟波1
作者信息
- 1. 河海大学水灾害防御全国重点实验室, 江苏 南京 210098;河海大学水安全与水科学协同创新中心, 江苏 南京 210098
- 2. 河海大学水安全与水科学协同创新中心, 江苏 南京 210098;南京水利科学研究院水灾害防御全国重点实验室, 江苏 南京 210029
- 折叠
摘要
蒸散发是地表水热平衡的关键要素,分析蒸散发的时空分布特征及其影响因素,对于深入理解区域水文循环与生态系统过程至关重要.基于通量观测站数据,评估GLEAM、MTE、GLDAS和AVHRR 共 4 种蒸散发产品在黄河流域水源涵养区的适用性,利用水量平衡方法验证其在流域尺度上的精度,并探讨实际蒸散发的影响因素.结果表明:在站点尺度上,GLEAM蒸散发产品精度最高;在流域尺度上,校正后的GLEAM蒸散发产品与实际蒸散发的相对误差在渭河南山支流区最小,其次是兰州以上地区;1982-2015 年黄河流域水源涵养区实际蒸散发整体呈增加趋势,空间分布上自西到东逐渐增加;不同植被类型年均蒸散发差异较大,阔叶林的蒸散发最大(575.2 mm),其次是农田(504.3 mm),高山草甸的蒸散发最小(358.2 mm);实际蒸散发变化主要受到太阳辐射与气温的影响.
Abstract
Evapotranspiration(ET)is an important component in the surface water-heat balance,and accurate analysis of the spatiotemporal distribution characteristics of evapotranspiration and its influencing factors is crucial for understanding the hydrological cycle and ecosystem of specific regions.Based on flux observatory data from the Yellow River basin water conservation area,we evaluated the applicability of four ET products,Global Land Evaporation Amsterdam Model(GLEAM),Model Tree Ensembles(MTE),Global Land Data Assimilation System(GLDAS),and Advanced Very High Resolution Radiometer(AVHRR),and applied the water balance principle to verify their accuracy at the basin scale,and to discuss the influencing factors of actual ET.Results showed that the GLEAM ET product had the highest accuracy at site scale.At basin scale,the relative errors of ETGLEAM and ETP-R were the smallest in a tributary basin of the Weihe River in the southern mountains,followed by the basin above Lanzhou.Actual ET in the water conservation area of the Yellow River basin showed an overall increasing trend during 1982-2015,and a gradual increase from the west toward the east in terms of spatial distribution.The annual average ET varied greatly among different vegetation types,with broadleaved forests showing the largest ET(575.2 mm),followed by farmland(504.3 mm),and alpine meadows showing the smallest ET(358.2 mm).Actual ET is mainly affected by solar radiation and temperature.
关键词
实际蒸散发/遥感蒸散发产品/通量观测/影响因素/水源涵养区/黄河流域Key words
actual evapotranspiration/remote sensing evapotranspiration products/flux observations/influencing factors/water conservation area/Yellow River basin引用本文复制引用
基金项目
国家重点研发计划(2021YFC3201104)
国家自然科学基金(U2240217)
出版年
2024
国家科技期刊平台
NSTL
万方数据