Radiocesium gamma dose rates in a Greek pine forest: measurements and Monte Carlo computations

Abstract

Publisher Summary The radiocesium distribution in an Aleppo pine forest ecosystem located in the Kassandra peninsula 105 km south of Thessaloniki, Macedonia, Northern Greece, was extensively studied during the past seven years. The radiocesium distribution in the different parts of the ecosystem was measured. A total 137Cs inventory of 150 MBqha−1 mainly due to the Chernobyl accident was measured in all parts of the ecosystem. The major part of this inventory (88%) is still in the upper 10 cm of the soil (84%) and the forest floor (4%). A small fraction of the inventory, less than 1%, is in the above-ground biomass. The 13Cs distribution in the soil follows an exponential decrease with depth and seems to level off to a constant value. It is probable that the same constant value also observed previously for other Greek forest sites describes the radiocesium concentration due to weapons fallout and indeed the exponential decrease, the radiocesium distribution due to the Chernobyl accident. The absorbed gamma dose rate in air 1 m above soil due to radiocesium was determined inside the ecosystem by combination of Monte Carlo computations with the MCNP code and in situ gamma spectroscopy measurement.