The mineral composition of soils and weathering processes are known to control the natural radioactivity of soils but research on the influence of water erosion and of main soil properties in the spatial variability of lithogenic and fallout radionuclides remains little investigated in heterogeneous agroecosystems with complex landscape. An extensive study was conducted to determine the mass activities of fallout (¹³⁷Cs, ²¹⁰Pb_ex) and lithogenic radionuclides (²³⁸U, ²²⁶Ra, ²³²Th, ⁴⁰K) an assess the main controls affecting their spatial variations in a representative 2.5 km² Pre-Pyrenean catchment of north-eastern Spain. The complex agroforestry catchment holds two distinctive parent materials, Muschelkalk limestones and Keuper argillaceous marls, in which the variability of the main soil properties and soil erosion patterns are well characterised. A total of 228 soil samples have been measured by using a high-purity germanium detector. Lithological influence on the variability of radionuclides was investigated and our results indicate that there are strong significant differences between the mass activities of ¹³⁷Cs, ²¹⁰Pb^ex, ²²⁶Ra and ⁴⁰K based on the two different parent materials. Positive correlations were found among the radioactivity contents of ²³²Th and ⁴⁰K and the clay content. Total organic carbon (SOC) was also positively correlated with ¹³⁷Cs, ²¹⁰Pbex and ²²⁶Ra activities, whereas carbonate content and SIC were negatively correlated with the radionuclides with higher significance in soils on limestones.

To gain knowledge on the spatial variability of the radionuclides within the landscape, maps of the distribution of radionuclides were generated by GIS interpolation tools of the entire set of measured activities and soil properties within a 100 × 100 m grid. The spatial patterns obtained, besides the variations of radionuclides along four selected transects, confirm the key role of water erosion in the mobilisation of fallout radionuclides, especially ¹³⁷Cs, while lithogenic radionuclides were sensitive to physical processes in areas where soil loss was intense. This study not only filled the gap of radioactivity data in agroforestry systems with contrasting parent materials, but also shed light on the potential of radionuclides for tracking soil redistribution processes in fingerprints studies.

已知土壤的矿物组成和风化过程可以控制土壤的自然放射性，但在景观复杂的非均质农业生态系统中，关于水蚀和主要土壤性质对成岩和沉降放射性核素空间变异性的影响的研究仍很少。进行了广泛的研究，以确定沉降（¹³⁷ Cs，²¹⁰ Pb _ex）和石质放射性核素（²³⁸ U，²²⁶ Ra，²³² Th，⁴⁰ K）的质量活动，并评估了在代表性的2.5 km中影响其空间变化的主要控制因素²西班牙东北部比利牛斯山前流域。复杂的农林业集水区拥有两种独特的母质，Muschelkalk石灰岩和Keuper泥质灰泥，其中主要土壤性质的变异性和土壤侵蚀模式得到了很好的表征。使用高纯度锗检测器对总共228个土壤样品进行了测量。研究了岩性对放射性核素变异性的影响，我们的结果表明，基于两种不同的母体材料，¹³⁷ Cs，²¹⁰ Pb ^ex，²²⁶ Ra和⁴⁰ K的质量活度之间存在很大的显着差异。在²³²的放射性含量之间发现正相关Th和⁴⁰ K以及粘土含量。总有机碳（SOC）也与¹³⁷ Cs，²¹⁰ Pbex和²²⁶ Ra活性呈正相关，而碳酸盐含量和SIC与放射性核素呈负相关，在石灰石上的土壤中具有更高的意义。

为了了解景观中放射性核素的空间变异性，使用GIS插值工具绘制了100×100 m网格内整套测量活动和土壤特性的放射性核素分布图。除了沿四个选定样带的放射性核素变化外，获得的空间格局还证实了水蚀在动员放射性放射性核素（尤其是¹³⁷ Cs）中的关键作用，而在土壤流失严重的地区，成石放射性核素对物理过程敏感。这项研究不仅用相反的母体材料填补了农林业系统中放射性数据的空白，而且还揭示了放射性核素在指纹研究中追踪土壤再分配过程的潜力。