Fig. 2From: Effects of nitrogen addition and drought on the relationship between nitrogen- and water-use efficiency in a temperate grasslandWUEINST (a–c), NUEINST (d–f), WUELT (g–i) and NUELT (j–l) of the six studied species under different treatments (C: control, N: N addition, D: drought, ND: combined drought and N addition). Data are shown as mean ± SE. Among them, a, d, g and j show the changes in grasses, b, e, h and k show the changes in the leguminous forb, c, f, i and l show the changes in non-leguminous forbs. Different lowercase letters above any two bars indicate significant differences among the treatments at p < 0.05Back to article page