Sustainable Use, Management, and Reclamation of Soil and Water Research Group, Technical University of Cartagena, Paseo Alfonso XIII, 52, 30203, Cartagena, Murcia, Spain.
Sustainable Use, Management, and Reclamation of Soil and Water Research Group, Technical University of Cartagena, Paseo Alfonso XIII, 52, 30203, Cartagena, Murcia, Spain.
Chemosphere. 2019 Mar;218:266-272. doi: 10.1016/j.chemosphere.2018.11.114. Epub 2018 Nov 20.
Several sequential extraction procedures are widely applied for metals chemical fractionation in the literature. However, their limitations to be used in different soils and metals have not been discussed in detail. This study compares two of the most commonly used extraction methods for metals chemical fractionation: Tessier and BCR. The objectives were to i) assess the differences between concentrations of metals extracted in each fraction by both Tessier and BCR procedures; ii) elucidate if soil properties affected the extraction ability of each fraction from both procedures; and iii) evaluate how land use contributes to different chemical metal distribution. Results indicated that both methods provide similar results when were applied to the same soil, since non-significant differences were found in metal concentrations between both methods at each fraction. Conversely, when we compared among land uses, significant differences were found in the metal concentration between both methods, especially between agricultural/urban/industrial against forest soil. Redundancy analysis showed that in carbonate-rich soils, BCR extraction method could cover up the real concentration of exchangeable metals with those bound to the carbonate phase, being the Tessier method the most suitable one for this kind of soils. Therefore, although sequential extraction is a useful tool to understand the distribution of metals in soil, the method used must be selected according to the land use and specific soil characteristics, taking into account at least, soil carbonate content.
几种连续提取程序在文献中被广泛应用于金属的化学形态分析。然而，它们在不同土壤和金属中的应用局限性尚未得到详细讨论。本研究比较了两种最常用于金属化学形态分析的提取方法：Tessier 和 BCR。目的是：i）评估两种方法在每个形态中提取的金属浓度之间的差异；ii）阐明土壤性质是否影响两种方法中每个形态的提取能力；iii）评估土地利用如何导致不同的化学金属分布。结果表明，当应用于同一土壤时，两种方法提供相似的结果，因为在每个形态中，两种方法之间的金属浓度没有显著差异。相反，当我们比较不同土地利用方式时，两种方法之间的金属浓度存在显著差异，特别是农业/城市/工业土壤与森林土壤之间。冗余分析表明，在碳酸盐丰富的土壤中，BCR 提取方法可能会掩盖可交换金属的真实浓度，而与碳酸盐相结合的金属，Tessier 方法是最适合这种土壤的方法。因此，尽管连续提取是了解土壤中金属分布的有用工具，但必须根据土地利用和特定土壤特性选择使用的方法，至少要考虑土壤碳酸盐含量。
