Radionuclides in natural terrestrial ecosystems.

p6osystems to be found in the maritime temperate zone are described. The part played by vegetation, animals and soils in the distribution and movement of radionuclides is discussed, with particular reference to natural systems. Biomass activities have been compiled for 137Cs and 239 + 240Pu in woodland and moorland ecosystems. The data indicate that these ecosystems are more effective at intercepting and retaining radionuclides than are agricultural systems and that many undisturbed soils function as efficient sinks.