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The vertical distributions and downward migrations of the global fallout derived Pu239+240 and Am-241 in diverse types of Chinese soils (forest, grassland and desert) were studied. The mean Pu239+240 and Am-241 activity concentrations in the investigated soil cores were 0.28-0.69 mBq/g and 0.13-037 mBq/g, respectively, while the accumulative inventories were 61.53-138.99 Bq/m(2) for Pu239+240 and 28.29-61.05 Bq/m(2) for Am-241. The convection-dispersion equation (CDE) was used to calculate the migration parameters of 239+240PU and higher apparent dispersion coefficients (D) were observed for the acidic forest soils compared with the alkaline grassland and desert soils; meanwhile a compartment model was employed to compare the migration of 239+240PU and Am-241 in successive soil layers which showed that the migration behaviors of 239+240PU and Am-241 were rather similar; both velocities were less than 0.3 cm/y in diverse types of soils and these findings were compatible with those of short-term laboratory simulation experiments in China. (C) 2018 Elsevier Ltd. All rights reserved.