摘要
蒸散发是水文和能量循环中的关键因素,蒸散发时空演变规律受到流域气候、能量和下垫面等多种复杂因素的综合影响。不同气候区流域蒸散发的影响因素存在时空差异性,具有不同的敏感性特征。研究蒸散发的时空变化规律有利于揭示复杂环境下流域水文循环的响应特征,进一步加深对流域水量平衡的认识,为流域水资源合理规划利用提供理论参考。基于SWH双源蒸散发模型,模拟鄱阳湖流域2001-2017年蒸散发及其组分,在多时空尺度验证的基础上,分析了流域蒸散发总量(ET)、土壤蒸发(Es)、植被蒸腾(Ec)和蒸发占比(Es/ET)的时空演变特征,基于SOBOL敏感分析方法探究了流域蒸散发组分的敏感影响因素和实际变化成因。结果表明,在8天尺度下SWH模型模拟值与实测值在站点和流域上的相关系数分别为0.92和0.89,模拟效果良好。在0.05显著性水平下,鄱阳湖流域年ET以1.0 mm/a的速率不显著下降,Es以2.6 mm/a的速率显著下降,Ec以1.7 mm/a的速率不显著增加,Es/ET以0.28%/a的速度显著下降。流域Es/ET呈现中间高、四周低的空间分布特征,冬季Es/ET>春季>秋季>夏季,其中除夏季以外Es/ET均呈显著下降趋势,主要集中在湖区南部平原和信江流域地区,占流域总面积的33.86%。气温和风速是影响流域ET和Es变化的主要敏感因素,其次为降水和净辐射,Es对植被指数NDVI也较为敏感。Ec和Es/ET在年、季尺度下的主要敏感因素均为植被指数NDVI,NDVI显著性增大是导致流域Ec和Es/ET变化的主要原因。
Evapotranspiration is a key factor in hydrological and energy cycles,and its spatio-temporal evolution is influenced by various complex factors such as watershed climate,energy,and underlying surface.The influencing factors of evapotranspiration in different climate regions have spatio-temporal differences and different sensitivity characteristics.Studying the spatio-temporal changes in evapotranspiration is beneficial for revealing the response characteristics of hydrological cycles in complex environments,further deepening people’s under⁃standing of water balance in watersheds,and providing theoretical reference for the rational planning and utilization of water resources in wa⁃tersheds.Based on the SWH dual source evapotranspiration model,the evapotranspiration and its components of the Poyang Lake Basin from 2001 to 2017 are simulated.On the basis of multi-temporal and spatial scale validation,the spatial-temporal evolution characteristics of the total evapotranspiration(ET),soil evaporation(Es),plant transpiration(Ec)and evaporation ratio(Es/ET)of the basin are analyzed.Based on the SOBOL sensitivity analysis method,the sensitive influencing factors and actual change causes of the evapotranspiration compo⁃nents of the basin are explored.The results show that the correlation coefficients between the simulated and measured values of the SWH mod⁃el at the 8-day scale are 0.92 and 0.89 at the station and watershed,respectively,indicating good simulation results.At the 0.05 significance level,the annual ET in the Poyang Lake Basin does not decrease significantly at the rate of 1.0 mm/a,Es decreases significantly at the rate of 2.6 mm/a,Ec does not increase significantly at the rate of 1.7 mm/a,and Es/ET decreases significantly at the rate of 0.28%/a.The spatial dis⁃tribution characteristics of Es/ET in the basin are high in the middle and low around,with Es/ET in winter>spring>autumn>summer.Except for summer,Es/ET shows a significant downward trend,mainly concentrated in the southern plain of the lake
作者
王钊
张润润
章阳
WANG Zhao;ZHANG Run-run;ZHANG Yang(College of Hydrology and Water Resources,Hohai University,Nanjing 210098,Jiangsu Province,China)
出处
《中国农村水利水电》
北大核心
2023年第11期52-63,共12页
China Rural Water and Hydropower
基金
国家自然科学基金项目(41701016)
中央高校基本科研业务费专项(B220202035)。
关键词
SWH双源模型
蒸散发
蒸发占比
时空变化
鄱阳湖流域
SWH dual-source model
actual evapotranspiration
evaporation ratio
spatio-temporal evolution
Poyang Lake Basin
