Abstract:Abruptly global climate change has easily led to an alarming increase in drought events, resulting in severe plant decline and mortality. Consequently, there is an urgent need to investigate the physiological mechanisms underlying plant death, particularly in trees, and develop predictive models to assess and predict the risk of plant mortality due to climate change. Plants employ various physiological processes to mitigate the impact of water stress, including adjusting the content of osmotic substances to balance osmotic potential, maintaining cell turgor, regulating the signal level of plant hormones to reduce stomatal aperture, which is conducive to water conservation, modulating the expression of plant aquaporins, and thus maintaining water stability in the body and swiftly responding to drought stress. Each of these physiological processes is regulated to ensure the efficiency and safety of water transport, increasing plant drought resistance and ecosystem stability. Drought resistance in plants is not only reflected in the regulation of physiological metabolism, but also in the complementary relationship between hydraulic traits and anatomical structures. When plants modify hydraulic traits, their stems and leaves will adjust their anatomical structures to meet the balance of water supply and demand in drought environment, thereby reducing the transpiration water loss of plants, enhancing cell water storage and improving their survival ability. Strategies for coping with water stress in plants are often related to the balance between water consumption and carbon acquisition. Clarifying the characteristics of the equilibrium relationship between water use and photosynthetic carbon acquisition is instrumental to understand the water use strategies of plants better. However, the strength of any single trait displayed by plants can not represent the strength or weakness of the whole plant adaptation to adversity. In order to predict the survival risks and ecological distributions of different plants in drought environment on a large scale, it is essential to integrate a variety of interconnected traits into the model system in the future, with a focus on traits representing plant hydraulic function, structure and photosynthetic capacity. In this paper, we provide a comprehensive review of the physiological and metabolic mechanisms of plants under drought stress while elucidating the relationships among plant hydraulic traits, anatomical structures, and photosynthesis. On the basis of existing studies, it points out the important significance of the development of plant hydraulic models and promotes the application of comprehensive plant traits in hydraulic and other models. This provides a basis for assessing current ecosystem plant survival risks and future ecosystem health levels.