Relationships among variables
Trait NC had negative correlations with REL RDPIs, and
positive correlations with ABS RDPIs, and trait CV
mainly had positive correlations with RDPIs (Fig. 2 and
Table S5). These correlations decreased over time in fertile soil, and
increased over time in infertile soil. Soil conditions, growth stage and
population density had more significant effects on correlations between
NC and ABS RDPIs, effects of growth stage and population
density were more significant for correlations between CV and REL
RDPIs (Table 3). For both stages, density effects on
correlations between NC and RDPIs and between CV and
RDPIs were more significant in fertile vs. infertile
soil (Table 4 and Fig. 2).