Identifying the spatiotemporal variations and influencing climate factors of evapotranspiration (ET) and its components (vegetation transpiration (Ec), soil evaporation (Es), and canopy interception evaporation (Ei)) can greatly improve our understanding of water cycle, carbon cycle, and biogeochemical processes in a warming climate. As the world′s largest hydropower project, the construction of the Three Gorges Project (TGP) coupled with the significant land use/land cover change affected the regional water and energy exchange in the Three Gorges Reservoir Area (TGRA). This study aimed to reveal the spatiotemporal variations and influencing climate factors in ET and its components using PML-V2 products in TGRA during 2000–2020. Results showed that the mean annual ET, Ec, Es, and Ei in TGRA were 585.12, 328.49, 173.07, and 83.56 mm, respectively. The temporal variation of ET was dominated by Ec, with no significant change in the time trend. Es decreased (2.92 mm/y) and Ei increased (1.66 mm/y) significantly mainly in the cultivated land. ET, Ec, and Ei showed a similar seasonal variation pattern with a single peak, while Es presented a bimodal pattern. From the pre-impoundment to the first impoundment period, ET and Ec mainly increased in the head of TGRA, meanwhile, Es in urban area increased significantly by 27.8%. In the subsequent impoundment periods, ET and Ec changed slightly while Es sharply decreased. The Ei increased persistently during different impoundment period. The dominant climate factors affecting changes in Ec and Es were air temperature, vapor pressure deficit, and sunshine hours, while the variation of Ei was mainly affected by air temperature, vapor pressure deficit, and precipitation.

中文翻译：

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三峡库区不同蓄水期陆地蒸散量及其组分的时空变化及影响因素

识别蒸散量 (ET) 及其组成部分（植被蒸腾量 (Ec)、土壤蒸发量 (Es) 和冠层截留蒸发量 (Ei)）的时空变化和影响气候因素可以大大提高我们对水循环、碳循环和气候变暖中的生物地球化学过程。作为世界上最大的水电项目，三峡工程（TGP）的​​建设以及土地利用/土地覆盖的显着变化影响了三峡库区（TGRA）的区域水和能源交换。本研究旨在利用 TGRA 中的 PML-V2 产品揭示 2000-2020 年期间 ET 及其组成部分的时空变化和影响气候因素。结果表明，TGRA 的年平均 ET、Ec、Es 和 Ei 分别为 585.12、328.49、173.07 和 83.56 mm。ET的时间变化以Ec为主，时间趋势无明显变化。Es 下降（2.92 mm/y），Ei 增加（1.66 mm/y），主要在耕地。ET、Ec 和 Ei 显示出类似的季节性变化模式，具有单峰，而 Es 呈现双峰模式。从蓄水前到第一蓄水期，ET和Ec主要在TGRA头部增加，同时市区Es显着增加27.8%。在随后的蓄水期，ET 和 Ec 略有变化，而 Es 急剧下降。不同蓄水期Ei持续升高。影响 Ec 和 Es 变化的主要气候因子是气温、水汽压差和日照时数，而 Ei 的变化主要受气温、水汽压差、