Fig. 1

Effects of N supply on mean (± SE, n = 4) concentrations of C and N, ratio of C/N, and distributions of N in C. sinensis leaves, stems and roots, contents of C and N, and ratio of C/N in plants. a, f and k Leaf, stem and root C concentrations. b, g and l Leaf, stem and root N concentrations. c, h and m C/N ratios in leaves, stems and roots. d, i and n C distributions in leaves, stems and roots. e, j and o N distributions in leaves, stems and roots. p, q and r Plant C content, N content and C/N ratio. Different letters above the bars indicate a significant difference at P < 0.05. The same notation will be used in Figs. 2-6