Figure 2
Temporal variations in 137Cs activity concentrations (decay-corrected to September 1, 2020) in the bark and wood of the monitoring trees. Circles show the observed values, and crosses indicate that the 137Cs concentration was below the (shown) detection limit. The true states were estimated using a dynamic linear model, and the median values and 95% credible intervals are shown by solid lines and shaded regions, respectively. Horizontal lines indicate significant differences between the estimated true state values in the years at both ends (delimiting years). Data on the bark (whole), wood (whole), sapwood, and heartwood from 2011 to 2016 were provided in previous studies8,25,31.
