摘要
气候和下垫面变化对流域蒸散发产生显著影响,然而,如何定量分解两者对蒸散发变异的贡献程度,一直以来是流域水文学研究的重点和难点。本研究基于水量与能量平衡基本原理,建立水量-能量分配空间坐标系统,分离并量化气候及下垫面变化对流域蒸散发的影响。基于优化的水量-能量分配框架,对全球83个典型流域的实际蒸散发变化(1900—2008年)进行归因研究,对比该方法与基于Budyko-Fu公式的分解法的计算成果,检验该框架在全球范围大尺度流域的科学性和适用性。结果发现,实际蒸散发的变化,在持水能力低的湿润流域主要受下垫面因素的驱动,而在持水能力强的湿润流域中主要受气候因素的影响;对于持水能力低的半湿润流域以及干旱与半干旱流域,其水热状态的变化轨迹主要沿干燥指数线移动,流域内实际蒸散发的变化主要受下垫面因素驱动。与已有基于Budyko-Fu公式的分解法计算结果的比较表明,本研究建立的基于水能分配框架的蒸散发归因方法具有较好的可靠度。此外,相对于传统的Budyko分解法,基于水量-能量分配法的水能空间坐标系能直观地分析气候及下垫面变化分别对流域实际蒸散发的贡献大小、方向及不同时段下流域水能状态的变化轨迹,具有较强的实用性。
Climate change and underlying surface variation jointly have significant impacts on evapotranspiration in river basins.However,how to quantitatively decompose contributions to variability of evapotranspiration still remains a focus as well as a crux in river basin hydrology.Based on the principle of water-energy balance,a spatial coordinate system of water-energy partitioning was established to quantify effects of climate and underlying surface variation on evapotranspiration separately.Then the optimized water-energy partitioning framework was applied to make attribution of actual evapotranspiration in 83 typical watersheds in 1900-2008.It is detected that variation of evapotranspiration in humid basins with low water holding capacity is mainly driven by underlying surface factors while in humid watershed with high water holding capacity,climate factors contribute more to evapotranspiration.The trajectory of hydro-thermal state in semi-humid,arid and semi-arid basins with low water-holding capacity mainly moves along the aridity index line,indicating that evapotranspiration is mainly driven by underlying surface factors.Comparing calculation results by this method with those based on Budyko-Fu decomposition method,it shows that the attribution method based on the water-energy partitioning framework has a good reliability.In addition,comparing to the traditional Budyko-Fu decomposition method,the spatial coordinate diagram of water-energy partitioning is able to intuitively analyze both contribution and direction of climate and underlying surface changes to evapotranspiration in river basins,as well as the change track of water-energy state in the basin under different periods,which might make a strong practicability in the future.
作者
缪贝儿
刘智勇
陈兴荣
蓝欣
陈晓宏
林凯荣
MIAO Beier;LIU Zhiyong;CHEN Xingrong;LAN Xin;CHEN Xiaohong;LIN Kairong(Center for Water Resources and Environment,School of Civil Engineering,Sun Yat-sen University,Guangzhou 510275,China;Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai),Zhuhai 519082,China)
出处
《水利学报》
EI
CSCD
北大核心
2022年第10期1229-1239,共11页
Journal of Hydraulic Engineering
基金
国家自然科学基金项目(52179031)
国家重点研发计划项目(2021YFC3001000)
珠江人才计划团队项目(2019ZT08G090)
广东省自然科学基金项目(2020A1515010559)。
关键词
水能分配空间坐标系
生态水文框架
Budyko-Fu分解法
归因分析
全球流域
spatial coordinate system of water-energy partitioning
ecohydrological framework
Budyko-Fu decomposition method
attribution analysis
global basins
