Abstract: Artificial light at night has become a common occurrence globally and may increase the risk of plant invasion. However, the effects of different intensities of artificial light at night on the growth of invasive and native plants are unclear. We individually cultivated five pairs of invasive and native plants from different families under ambient light, low artificial light at night, and high artificial light at night. Our study showed that the total biomass of both invasive and native plants increased significantly under low artificial light at night. However, while the total biomass of invasive plants increased significantly, that of native plants was significantly decreased under high artificial light at night. These findings indicate that invasive plants can better utilize light energy and have more effective photosynthetic response mechanisms under artificial light at night, while the photosynthesis of native plants is inhibited. The leaf dry matter content, and leaf nitrogen content of invasive plants were significantly higher than those of native plants under artificial light at night, and artificial light at night significantly improved the photosynthetic nitrogen use efficiency of invasive plants. This indicates that invasive plants have stronger phenotypic plasticity and nitrogen-distribution strategy under artificial light at night. In summary, the better physiological response of invasive plants compared with native plants under different intensities of artificial light at night may lead to the further spread of invasive plants in the ecosystem.

Key words: Artificial light at night, Invasive plants, Native plants, Photosynthetic rate, Leaf traits, Biomass