Temporal trajectories of artificial radiocaesium 137Cs in French rivers over the nuclear era reconstructed from sediment cores
Abstract
137Cs is a long-lived man-made radionuclide introduced in the environment worldwide at the early
beginning of the nuclear Era during atmospheric nuclear testing’s followed by the civil use of nuclear
energy. Atmospheric fallout deposition of this major artificial radionuclide was reconstructed at
the scale of French large river basins since 1945, and trajectories in French nuclearized rivers were
established using sediment coring. Our results show that 137Cs contents in sediments of the studied
rivers display a large spatial and temporal variability in response to the various anthropogenic
pressures exerted on their catchment. The Loire, Rhone, and Rhine rivers were the most affected by
atmospheric fallout from the global deposition from nuclear tests. Rhine and Rhone also received
significant fallout from the Chernobyl accident in 1986 and recorded significant 137Cs concentrations in
their sediments over the 1970–1985 period due to the regulatory releases from the nuclear industries.
The Meuse River was notably impacted in the early 1970s by industrial releases. In contrast, the
Seine River display the lowest 137Cs concentrations regardless of the period. All the rivers responded
similarly over time to atmospheric fallout on their catchment, underlying a rather homogeneous
resilience capacity of these river systems to this source of contamination.
| Origin | Publisher files allowed on an open archive |
|---|---|
| licence |
