Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
Foreign Environmental Cooperation Center, Ministry of Ecology and Environment, Beijing, 100035, China.
Environ Pollut. 2022 Nov 15;313:120099. doi: 10.1016/j.envpol.2022.120099. Epub 2022 Sep 6.
Rare earth elements (REEs) concentrated in soils have attracted increasing attention about their impact on soil health as emerging contaminants. However, the sources of REEs enriched in soils are diverse and need to be further investigated. Here, surface soil samples were collected from southern Jiangxi Province, China. REEs contents and soil physicochemical properties were determined, and cerium (Ce) and europium (Eu) anomalies were calculated. Moreover, we established a model to further identify the main sources of REEs accumulation in the studied soils. Results show that the abundance of soil REEs reveals larger spatial variation, suggesting spatially heterogeneous distribution of REEs. The median content of light REEs in soils (154.5 mg kg) of the study area was higher than that of heavy REEs and yttrium (35.8 mg kg). In addition, most of the soil samples present negative Ce anomalies and all the soil samples present negative Eu anomalies implying the combined effect of weathering and potential exogenous inputs on soil REEs. Positive matrix factorization modeling reveals that soil REEs content is primarily influenced by soil parent materials. Potential anthropogenic sources include mining-related leachate, traffic exhaust, and industrial dust. These results demonstrate that the identification of sources of soil REEs is an important starting point for targeted REEs sources management and regulation of excessive and potentially harmful REEs levels in the soil.
稀土元素（REEs）在土壤中的富集引起了越来越多的关注，因为它们作为新兴污染物会对土壤健康造成影响。然而，土壤中 REEs 的来源多样，需要进一步研究。本研究采集了中国江西南部的表层土壤样品。测定了 REEs 含量和土壤理化性质，并计算了铈（Ce）和铕（Eu）异常。此外，我们建立了一个模型，以进一步确定研究土壤中 REEs 积累的主要来源。结果表明，土壤 REEs 的丰度存在较大的空间变化，表明 REEs 具有空间异质性分布。研究区域土壤轻 REEs（154.5 mg kg）的中位数含量高于重 REEs 和钇（35.8 mg kg）。此外，大多数土壤样品呈现负铈异常，所有土壤样品呈现负铕异常，这表明风化和潜在外源输入对土壤 REEs 具有综合影响。正矩阵因子分解模型表明，土壤 REEs 含量主要受土壤母质的影响。潜在的人为来源包括与采矿有关的浸出液、交通废气和工业粉尘。这些结果表明，识别土壤 REEs 的来源是针对 REEs 来源进行管理和调控土壤中过量和潜在有害 REEs 水平的重要起点。
