Soil type can determine invasion success of Eichhornia crassipes.
Invasive species benefit from advantageous trait values and/or trait plasticity in their invasion process when facing changing environments. However, few studies explored this mechanism on invasive macrophytes. The effects of soil on the invasion of macrophytes were studied little by previous researches. In the measurement of several traits related to resource utilization, we studied the plant responses to three representative types of riparian soil in Liangzi Lake, China. Using multi-species comparison, we explored the differences of trait values and trait plasticity among Eichhornia crassipes (Mart.) Solms and its non-invasive confamilial counterparts all in emergent life-form-exotic Pontederia cordata L. and native Monochoria vaginalis (Burm. f.) Presl ex Kunth. We measured leaf-level and root-level traits after harvest. We found that E. crassipes mainly showed trait value advantages in root-level traits in infertile soils, while some advantages of leaf-level traits were present but not obvious compared to the two confamilials. Besides, E. crassipes showed higher plasticity in several traits especially in some root-level traits than the two confamilials. We concluded that both trait values and trait plasticity especially in belowground traits play a crucial role in the invasion success of emergent E. crassipes.