The 2011 Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, Japan, released the largest quantity of radionuclides into the terrestrial environment since the 1986 accident at Chernobyl. This accident resulted in 2.7 PBq of radiocaesium (¹³⁷Cs) contaminated forests, agricultural lands, grasslands and urban areas, which subsequently migrated through soil and waterways in the Fukushima Prefecture. In this Review, we synthesize knowledge regarding the deposition, distribution and transport of fallout radionuclides, especially ¹³⁷Cs, in the terrestrial environment after the FDNPP accident, which were revealed by extensive and continuous environmental monitoring. Anthropogenic activities, high run-off and steep topography led to a rapid decline in the activity concentration of ¹³⁷Cs in soils and rivers, especially in the first year after the accident. The decline in exposed radioactivity was notably faster than that seen after the Chernobyl Nuclear Power Plant accident, likely related to differences in geography and climate, and the intensive remediation activities in Fukushima. However, forests in Fukushima have retained a notable amount of ¹³⁷Cs in the upper centimetres of soil and could persist as a source of ¹³⁷Cs into rivers. For continued understanding of both natural and fallout radionuclide behaviour in the environment, there must be long-term accessibility of the data collected in response to the FDNPP accident.

日本的2011年福岛第一核电站事故（FDNPP）是自1986年切尔诺贝利事故以来向陆地环境释放的最大放射性核素。这次事故导致了2.7 PBq（¹³⁷ Cs）的放射性铯污染的森林，农田，草地和城市地区，随后在福岛县的土壤和水道中迁移。在本综述中，我们综合了FDNPP事故后陆地环境中放射性放射性核素（尤其是¹³⁷ Cs）的沉积，分布和运输的知识，这些知识通过广泛而持续的环境监测得以揭示。人为活动，高径流量和陡峭的地形导致活动浓度迅速下降。土壤和河流中的¹³⁷ Cs，尤其是事故发生后的第一年。暴露的放射性下降明显快于切尔诺贝利核电站事故后的下降速度，这可能与地理和气候的差异以及福岛县的密集整治活动有关。但是，福岛的森林在土壤的上厘米处保留了¹³⁷ Cs的显着量，并且可以作为河流中¹³⁷ Cs的来源持续存在。为了继续了解环境中自然放射性核素和放射性放射性核素的行为，必须对FDNPP事故做出响应，才能长期收集所收集的数据。