Fig. 6

Tracer concentration of ¹⁵N, Li, Cs, Se and Rb in alfalfa shoot biomass affected by core-labelling depth (1.0 and 2.5 m; a–e) sampling distance (core-, around- and remote-spot; f–j) in the spring experiment. Roman letters indicate significant differences between the treatments (HSD Tukey; P ≤ 0.05). Means and one SE are shown