Study sites and horizontal distribution of radiocesium. Map showing the location of the study sites in Fukushima prefecture (A) and the deposition of radiocesium (i. e. the sum of 134Cs and 137Cs) for the land area within 80 km of the F1NPP site, as reported by the Japanese authorities (MEXT) (B). Fukushima prefecture has five regions, i.e. the Sousou, Iwaki, Fukushima, Koriyama and Aizu regions, which are divided by thick lines on the map. Closed symbols indicate the location where samples were collected. The map of deposition of radiocesium deposition (B) was downloaded from http://www.iaea.org/newscenter/news/2011/fukushimafull.html on 2 June 2014.