Guidotti Laura, Carini Franca, Rossi Riccardo, Gatti Marina, Cenci Roberto M, Beone Gian Maria
Istituto di Chimica Agraria ed Ambientale, Facoltà di Scienze Agrarie, Alimentari e Ambientali, Università Cattolica del Sacro Cuore, Via Emilia Parmense 84, 29122 Piacenza, Italy.
Istituto di Chimica Agraria ed Ambientale, Facoltà di Scienze Agrarie, Alimentari e Ambientali, Università Cattolica del Sacro Cuore, Via Emilia Parmense 84, 29122 Piacenza, Italy.
J Environ Radioact. 2015 Apr;142:36-44. doi: 10.1016/j.jenvrad.2015.01.010. Epub 2015 Jan 27.
This work is part of a wider monitoring project of the agricultural soils in Lombardia, which aims to build a database of topsoil properties and the potentially toxic elements, organic pollutants and gamma emitting radionuclides that the topsoils contain. A total of 156 agricultural soils were sampled according to the LUCAS (Land Use/Cover Area frame statistical Survey) standard procedure. The aim was to provide a baseline to document the conditions present at the time of sampling. The results of the project concerning soil radioactivity are presented here. The aim was to assess the content of (238)U, (232)Th, (137)Cs and (40)K by measuring soil samples by gamma spectrometry. (238)U, (232)Th and (40)K activities range 24-231, 20-70, and 242-1434 Bq kg(-1) respectively. The geographic distribution of (238)U reflects the geophysical framework of the Lombardia region: the soils with high content of uranium are distributed for the most part in the South Alpine belt, where the presence of magmatic rocks is widespread. These soils show an higher activity of (238)U than of (232)Th. The (238)U activities become lower than (232)Th when soils are located in the plain, originating from basic sedimentary rocks. (137)Cs activity ranges 0.4-86.8 kBq m(-2). The lowest activity of (137)Cs is in the plain, whereas the highest is in the North on soils kept as lawn or pasture. The (137)Cs activity of some samples suggests the presence of accumulation processes that lead to (137)Cs enriched soils. This is the first survey of gamma emitting radionuclides in Lombardia that is based on the LUCAS standard sampling. The results from this monitoring campaign are important for the human radiation exposure and provide the zero point, which will be useful for assessing future effects due to external factors such as human activities.
这项工作是伦巴第大区农业土壤更广泛监测项目的一部分，该项目旨在建立一个表土属性以及表土中所含潜在有毒元素、有机污染物和伽马发射放射性核素的数据库。根据LUCAS（土地利用/覆盖面积框架统计调查）标准程序，共采集了156份农业土壤样本。目的是提供一个基线，以记录采样时的现状。本文展示了该项目有关土壤放射性的结果。目的是通过伽马能谱法测量土壤样本，评估（238）U、（232）Th、（137）Cs和（40）K的含量。（238）U、（232）Th和（40）K的活度分别在24 - 231、20 - 70和242 - 1434 Bq kg(-1)范围内。（238）U的地理分布反映了伦巴第大区的地球物理框架：铀含量高的土壤大部分分布在南阿尔卑斯带，那里岩浆岩分布广泛。这些土壤显示出（238）U的活度高于（232）Th。当土壤位于源自基性沉积岩的平原地区时，（238）U的活度低于（232）Th。（137）Cs的活度在0.4 - 86.8 kBq m(-2)范围内。（137）Cs的最低活度出现在平原地区，而最高活度出现在北部用作草坪或牧场的土壤中。一些样本的（137）Cs活度表明存在导致土壤中（137）Cs富集的积累过程。这是伦巴第大区首次基于LUCAS标准采样进行的伽马发射放射性核素调查。这次监测活动的结果对于人类辐射暴露非常重要，并提供了零点，这将有助于评估未来诸如人类活动等外部因素造成的影响。
