The Plant Functional Traits of Arid and Semiarid Grassland Plants under Warming and Precipitation Change

In recent years, climate change has produced a trend of temperature rising and fluctuation of annual precipitation in arid and semiarid grassland ecosystem, which has an impact on grassland plant functional traits including plant morphology, photosynthesis, and respiration efficiency. The dominant species in China’s arid and semiarid grassland are Stipa krylovii, Stipa breviflora, Leymus chinensis, and other common steppe species. This study summarized the results of temperature and precipitation change test in the growing season in China’s arid and semiarid grassland and analyzed the change rule of plant functional traits of typical species. According to several test results, the plant functional traits generally changed as follows: (1) plant height showed declined trend under warming and dry condition, but plant total leaf number and leaf area increased, and root-top ratio decreased as temperature and precipitation went up. (2) Chlorophyll content and plant photosynthesis and respiration efficiency grew under warming and high precipitation. (3) Hydrothermal conditions had synergistic effect on plant functional traits; increased precipitation helped grassland species to resist high-temperature stress. This study contributed to an understanding of plant morphology and physiological response to climate change of dominant species in China’s arid and semiarid grassland