Conclusion

Partitioning the variance among multiple ecological scales allows to get a less fragmented picture of all possible underlying variables that can drive community assembly and avoid misinterpretations of traits variations in field studies. Moreover, while many studies focused on mean trait values, we aim to consider the strong role of ITV in species coexistence and their responses to filters. To go further, we plead to consider other trait metrics in future studies to better describe trait distributions and assess the processes underlying plant community assembly. As for example, skewness and kurtosis (Enquist et al., 2015; Gross et al., 2017) are a complement to the mean and the variance and reflect respectively trait distribution asymmetry and the evenness of functional diversity. As such, they could be indicative of competition (Gross et al., 2009; Schamp et al., 2007) or rapid environmental change (Enquist et al., 2015; Le Bagousse-Pinguet et al., 2017). Consequently, these metrics would be very useful to predict for responses to changing environment or their effects on ecosystem functioning (Gross et al., 2017).