Figure 4. Plots of cases and variables in the PCAs conducted with the elemental, stoichiometric, and metabolomic variables in plants sampled in September.

(A) Plot of cases and variables for shoots. (B) Plot of cases and variables for roots. C/N/P/K ratios are shown in red. The various metabolomic families are represented by colours: blue, sugars; green, amino acids; dark green, amino-acid derivatives; yellow, related compounds to the amino acids and sugars metabolism; cyan, nucleotides; violet, osmolytes; and brown, terpenes and phenols. Variables are coloured and labelled as described in the caption for Fig. 1. The means of the cases are indicated by colour: blue, irrigated control; green, ambient control; and orange, drought. Holcus lanatus is indicated as Holcus and Alopecurus pratensis as Alopecurus.