Fig. 4 Correlations between SW and leaf stoichiometry. SW, soil water content; LN, Leaf nitrogen content; LP, Leaf phosphorus content; LK, Leaf potassium content; LN:LP, Ratio of leaf nitrogen content to leaf phosphorus content; LN:LK, Ratio of leaf nitrogen content to leaf potassium content; LP:LK, Ratio of leaf phosphorus content to leaf potassium content.