The increased demand for technology-critical elements (TCEs) in emerging technologies brings about the need to determine their spatial distribution in the environment and establish regulatory guidelines. In this paper, concentrations of Li, Sc, Nb, W, Ga, Ge, and REY (rare earth elements, including yttrium) in soils collected from different parent materials in the upper catchment of the Sava River (Slovenia, Croatia) were analysed. Results of multivariate (principal component analysis) and univariate (threshold methods) statistical techniques were used to determine geochemical characteristics of studied soils to identify the background variations and to establish geochemical threshold values. The investigated area is characterized by great lithological diversity and substantial variation of TCE concentrations. Among methods for assessment of geochemical threshold, the TIF (Tukey inner fence) and 97.5th percentile delivered the most reasonable results. Some exceedances above the 97.5th percentile were natural in origin, caused by local geology. These findings can provide baseline data because little is known about TCE variation on different geological substrata.

新兴技术对关键技术要素 (TCE) 的需求不断增加，因此需要确定它们在环境中的空间分布并制定监管指南。本文分析了从萨瓦河上游流域（斯洛文尼亚、克罗地亚）不同母质收集的土壤中 Li、Sc、Nb、W、Ga、Ge 和 REY（稀土元素，包括钇）的浓度. 多变量（主成分分析）和单变量（阈值方法）统计技术的结果用于确定研究土壤的地球化学特征，以确定背景变化并建立地球化学阈值。调查区域的特点是岩性多样性很大，TCE 浓度变化很大。在地球化学阈值的评估方法中，TIF（Tukey 内围栏）和第 97.5 个百分位给出了最合理的结果。一些超过 97.5% 的超标是由当地地质引起的自然原因。这些发现可以提供基线数据，因为对不同地质基质上的 TCE 变化知之甚少。