Spatial-temporal heterogeneity and controlling factors of evapotranspiration in Nujiang River Basin based on Variable Infiltration Capacity(VIC)model  

作　　者：ZHANG Xianhe LIU Shiyin ZHU Yu XIE Fuming 

机构地区：[1]Institute of International Rivers and Eco-Security,Yunnan University,Kunming 650091,China [2]Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security,Yunnan University,Kunming 650091,China [3]Yunnan International Joint Laboratory of China-Laos-Bangladesh-Myanmar Natural Resources Remote Sensing Monito ring,Kunming 650091,China

出　　处：《Journal of Mountain Science》2024年第11期3598-3614,共17页山地科学学报（英文）

基　　金：supported by the National Natural Science Foundation of China(42171129);the second Tibetan Plateau Scientific Expedition and Research(2019QZKK0208);Yunnan University Talent Introduction Research Project(YJRC3201702)。

摘　　要：Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by large elevation gradient and different vegetation zones with complex processes of water and energy exchange.The quality of ET from optical remote sensing is constrained by cloud cover which is common in the NRB in the monsoon seasons.To understand factors controlling the spatial-temporal heterogeneity of ET in NRB,we employed the Variable Infiltration Capacity(VIC)hydrological model by parameter optimization with support of quality controlled remote sensing ET product and observed river runoff series in the river.The modeled ET has increased during 1984-2018,which might be one of the reasons for the runoff decrease but precipitation increase in the same period.ET increase and runoff decrease tended to be quicker within altitudinal band of 2000-4000 m than in other areas in NRB.We observed that ET variation in different climatic zones were controlled by different factors.ET is generally positively correlated with precipitation,temperature,and shortwave radiation but negatively with relative humidity.In the Tundra Climate(Et)zone in the upper reach of NRB,ET is controlled by precipitation,while it is controlled by shortwave radiation in the snow climate with dry winter(Dw)zone.ET increase is influenced by the increase of temperature,wind speed,and shortwave radiation in the middle and downstream of NRB with warm temperate climate,fully humid(Cf)and warm temperate climate with dry winter(Cw).

关 键 词：EVAPOTRANSPIRATION Variable infiltration capacity(VIC)model Spatial temporal heterogeneity Climate change Controlling factors Nujiang River Basin 

分 类 号：P333.1[天文地球—水文科学]