Spatial distribution and variability of 239+240 Pu in surface soil of China

Abstract

In order to understand the range of 239+240Pu and 240Pu/239Pu that the data from the literature published in 1991 to 2019, spatial distribution and variability of 239+240Pu and 240Pu/239Pu in Chinese surface soil were quantitatively analyzed by statistical analysis and mathematical model. The results showed that the atom ratio of 240Pu/239Pu in Chinese surface soil was concentrated at 0.18(99%), the global fallout was the main source of 239+240Pu in the surface soil of China; 239+240Pu was at a low radiation level (≤1Bq/kg, 94%) in the surface soil, and the 239+240Pu of Northwest and Northeast China had a high spatial variability. The 239+240Pu distribution were affected by atmospheric mixing, canopy effect, soil particle size, organic matter and migration (horizontal and vertical migration). At the same time, this study systematically combed out the mathematical model for calculating the spatial variation of 239+240Pu in surface soil of China, providing an effective method for quantitative assessment of the environmental level of 239+240Pu. Show more