Abstract As one of the typical underlying surfaces on the Qinghai-Tibetan Plateau (QTP), alpine wetlands play a very important role in runoff regulation and affect climate change in downstream regions. However, the mechanisms of the latent heat transfer and coupling processes between the alpine wetland and atmosphere have rarely been investigated with a combination of land surface models. In this paper, the hydrometeorological factors are analyzed, the coupling degree is quantified, and the controlling factors are discussed. Alpine wetland has a hysteretic response to the net radiation, and the dominant factor controlling the latent heat flux is downward shortwave radiation (Rs), which intensely promoting the exchange of latent heat flux in the daytime. Biological control exercised by Rs is positive and decreasing with the increasing of Rs, while biological control exercised by water vapor pressure deficit (D) is negative and increasing with the increasing of D. The coupling degree is low from 9:00–17:00 when latent heat flux is mainly controlled by Rs and high in the early morning and 19:00 when D is the dominant factor. This study contributes to understanding land surface processes and protecting alpine wetland ecosystems on the QTP.

中文翻译：

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青藏高原夏季高寒湿地与大气耦合度控制因素评价

摘要 高寒湿地作为青藏高原典型的下垫面之一，在径流调节和下游地区气候变化中发挥着非常重要的作用。然而，很少结合地表模型研究高山湿地与大气之间的潜热传递和耦合过程的机制。本文分析了水文气象因素，量化了耦合度，讨论了控制因素。高寒湿地对净辐射具有滞后响应，控制潜热通量的主导因素是向下的短波辐射（Rs），强烈促进了白天潜热通量的交换。Rs 的生物控制是正的，随着 Rs 的增加而减少，而水汽压差（D）的生物防治为负值，并随着D的增加而增加。 9:00-17:00潜热通量主要受Rs控制时耦合度低，清晨时耦合度高和 19:00 当 D 是主导因素。本研究有助于了解青藏高原陆面过程和保护高山湿地生态系统。