关键词: 根系分泌速率, 植物功能性状, 增温, 高寒草甸, 植物经济型谱

Abstract: Abstract Aims Plant root exudates have received increasing attentions as a key link in plant-soil-microbe interactions in recent years. However, studies on the impact of climate warming on the root exudation rates of grassland plants remain relatively limited. Methods In this study, we conducted a laboratory controlled experiment with 10 dominant plant species in alpine meadows of the Tibetan Plateau. We collected root exudates in situ to quantitatively analyze the changes in root carbon exudation rates of the dominant species under experimental warming (+ 4 °C) and identified the factors influencing these changes. Important findings Our results showed that: (1) Warming significantly increased the root carbon exudation rate of most dominant species, with an overall increase of 83.48 ± 6.00 μg·g-1·h-1, but it decreased the root exudation rate in leguminous plants; (2) The changes in root exudation rates induced by warming were closely related to plant traits, with root nitrogen content explaining the highest variation in root exudation rates under warming conditions. These findings suggest that climate warming will enhance the root exudation rates of dominant species in alpine meadows and highlight the critical role of functional traits in regulating root exudation responses to warming. This study contributes to the understanding of rhizosphere carbon dynamics in the context of climate change and provides scientific evidence for further predicting changes in the soil carbon dynamics of the Qinghai-Tibet Plateau.

Key words: root exudation rate, plant functional trait, climate warming, alpine meadow, plant economics spectrum