Modelling seasonal variations of natural radioactivity in soils: A case study in southern Italy

Abstract

The activity of natural radionuclides in soil has become an environmental concern for local public and national authorities because of the harmful effects of radiation exposure on human health. In this context, modelling and mapping the activity of natural radionuclides in soil is an important research topic. The study was aimed to model, in a spatial sense, the soil radioactivity in an urban and peri-urban soils area in southern Italy to analyse the seasonal influence on soil radioactivity. Measures of gamma radiation naturally emitted through the decay of radioactive isotopes (potassium, uranium and thorium) were analysed using a geostatistical approach to map the spatial distribution of soil radioactivity. The activity of three radionuclides was measured at 181 locations using a high-resolution γ-ray spectrometry. To take into account the influence of season, the measurements were carried out in summer and in winter. Activity data were analysed by using a geostatistical approach and zones of relatively high or low radioactivity were delineated. Among the main processes which influence natural radioactivity such as geology, geochemical, pedological, and ecological processes, results of this study showed a prominent control of radio-emission measurements by seasonal changes. Low natural radioactivity levels were measured in December associated with winter weather and moist soil conditions (due to high rainfall and low temperature), and higher activity values in July, when the soil was dry and no precipitations occurred.

The De Martonne aridity index in Calabria (Southern Italy)

“…(Ricca & Guagliardi, 2015). The Calabrian climate is generally Mediterranean but the rather complex orographic characteristics of this territory, combined with the simultaneous exposure to the Tyrrhenian Sea (which implies more continental climate in the coast compared to the Ionian side) and to the Ionian Sea (which implies high temperatures and short and abundant rainfall due to frequent African warm air currents) makes the climate of this territory very changeable and complex (Guagliardi et al, 2013(Guagliardi et al, , 2016(Guagliardi et al, , 2018.…”

Radionuclides Transfer from Soil to Tea Leaves and Estimation of Committed Effective Dose to the Bangladesh Populace

“…The surface soil, especially the top layer in the earth, is a mixture of various components in the natural environment [ 6 , 7 ]. Although the main source of U, Th and K is the earth crust, their contents appear at varying levels in the soils of different regions in the world following the variation of the local geology [ 8 ].…”

Geochemical Characterization of Spring Waters in the Crati River Basin, Calabria (Southern Italy)

“…Description of the Sampling Site. The Crati, located in the NW sector of the Calabria region, is the main basin in the region both for its extension and for its artificial lakes [32]. It has a perimeter of about 320 km and an area of 2447.7 km 2 within which a wide hydrographical network flows, including waters coming from different geological environments.…”