Priority Effects Favor Invasive over Its Native Congener , While Late Arrival Incurs Higher Costs.

Priority effects-the phenomenon where early-arriving species influence the establishment, growth, and reproduction of later-arriving species during community assembly-play a critical role in determining the invasion success of exotic species. However, how priority effects are influenced by nitrogen (N) availability remains understudied. The invasive species has rapidly expanded its range in China over the past few years. Yet it remains unclear how priority effects in versus native species may mediate invasion success, as well as how nutrient levels may alter these effects. Addressing these questions is essential for understanding the mechanisms driving invasion and for developing effective management strategies. In a greenhouse experiment, we manipulated the planting order of and its native congener , then measured the growth and competitiveness of and in both control and N addition treatments. Planting order greatly impacted the growth and competitiveness of both and . Early arrival had more positive effects on than , while late arrival more strongly inhibited than . For , priority effects lessened with nitrogen addition, but the opposite occurred for . Thus, priority effects may favor invasion, while late arrival, particularly under nitrogen addition, may curb its spread. As such, sowing early-germinating native species represents a useful management strategy for controlling invasions.