Fig. 2

Radial distribution of ¹³⁷Cs activity concentration in wood sampled at different vertical positions in 2014. a–f Japanese cedar (Cryptomeria japonica); g–i Japanese cypress (Chamaecyparis obtusa); j, k Japanese larch (Larix kaempferi). ND letters indicate that ¹³⁷Cs activity in the samples was under the detection limit and show the detection limit values. SW sapwood, HW heartwood, DBH diameter at breast height, TH tree height, LBH lowest branch height, HWMC heartwood moisture content (mean moisture content of samples collected at 2.5 and 4.5 m height)