Figure 5
Temporal variations of δ13C in shoot (a), root (c), soil TC (e) and δ15N in shoot (b), root (d), soil TN (f), NH4 +-N (g) and NO3 −-N (h). Error bars represent standard error (n = 3). CK: Normal fertilization with no γ-PGA application, γ-PGA: Normal fertilization with application of 350.44 mg γ-PGA kg−1 soil. **p < 0.01, *p < 0.05.
