干旱区地理2025，Vol.48Issue(5)：753-764,12.DOI:10.12118/j.issn.1000-6060.2024.395
青藏高原东北部实际蒸散发时空变化特征及影响因素
Spatiotemporal variation of actual evapotranspiration and its influencing factors in the northeast Qinghai-Xizang Plateau
摘要
Abstract
The spatiotemporal characteristics and influencing factors of actual evapotranspiration(ET)in the northeastern Qinghai-Xizang Plateau are crucial for the effective management of regional water resources and the ecological environment.Using Qinghai Province,located in this region,as the study area,this study analyzed ac-tual ET data(MOD16 ET)from 2001 to 2020 to explore the spatiotemporal patterns,variation trends,and influ-encing factors over the past 20 years.The results indicate the following:(1)The average annual actual evapotrans-piration in Qinghai Province from 2001 to 2020 was 260 mm·a-1,showing a fluctuating increasing trend.The fluctuation period also showed an increasing trend,with an average interannual change rate of 2%.Areas where actual ET increased accounts for 69.69%of the total area,and areas where it decreased accounted for 16.51%.Among them,the Qilian Mountains area and the eastern part of the river source ecological zone exhibited an in-creasing trend in actual ET.The seasonal variation of actual ET in Qinghai Province was significant,with the maximum in summer,the minimum in winter,and similar values in spring and autumn.(2)The average actual ET in Qinghai Province from 2001 to 2020 showed a spatial distribution characteristic of being low in the northwest and high in the southeast.There were large differences in actual ET among various ecological zones in Qinghai Province,with the Three River Source area and the Qilian Mountains area exhibiting the largest actual ET distri-bution,and the Qaidam Basin ecological zone had the smallest actual ET.The actual ET of the main vegetation cover types was ranked as follows:shrubland>forest land>grassland>arable land.(3)The fluctuating changes in actual ET in Qinghai Province from 2001 to 2020 were basically consistent with temperature variations.The in-crease in actual ET largely corresponded to the increasing trend of precipitation fluctuations,but the peak lagged behind changes in precipitation.(4)Actual ET was positively correlated with annual average temperature,annual total precipitation,sunshine duration,and average wind speed in 73%,56%,43%,and 44%of the total study ar-ea,respectively.Temperature and precipitation were the primary controlling factors of actual ET,whereas sun-shine duration and wind speed also exerted notable influences.There were significant regional differences in the factors affecting the changes in actual evapotranspiration.关键词
蒸散发/时空变化/影响因素/青藏高原东北部/青海省Key words
evapotranspiration/spatiotemporal variation/influencing factors/northeast Qinghai-Xizang Pla-teau/Qinghai Province引用本文复制引用
卢晗,曾永年,王盼成..青藏高原东北部实际蒸散发时空变化特征及影响因素[J].干旱区地理,2025,48(5):753-764,12.基金项目
国家自然科学基金项目(42171364)资助 （42171364）
