A high-resolution soil sampling has been applied to two forest podzols (ACB-I and ACB-II) from SW Europe in order to investigate the soil components and processes influencing the content, accumulation and vertical distribution of Hg. Total Hg contents (THg) were 28.0 and 23.6 μg kg⁻¹ in A horizons of ACB-I and ACB-II, then they strongly decreased in the E horizons and peaked in the Bhs horizons of both soils (55.3 and 63.0 μg kg⁻¹). THg decreased again in BwC horizons to 17.0 and 39.8 μg kg⁻¹. The Bhs horizons accounted for 46 and 38% of the total Hg stored (ACB-I and ACB-II, respectively). Principal component analysis (PCA) and principal components regression (PCR), i.e. using the extracted components as predictors, allowed to distinguish the soil components that accounted for Hg accumulation in each horizon. The obtained model accurately predicted accumulated Hg (R² = 0.845) through four principal components (PCs). In A horizons, Hg distribution was controlled by fresh soil organic matter (PC4), whereas in E horizons the negative values of all PCs were consistent with the absence of components able to retain Hg and the corresponding very low THg concentrations. Maximum THg contents in Bhs horizons coincided with the highest peaks of reactive Fe and Al compounds (PC1 and PC2) and secondary crystalline minerals (PC3) in both soils. The THg distribution in the deepest horizons (Bw and BwC) seemed to be influenced by other pedogenetic processes than those operating in the upper part of the profile (A, E and Bhs horizons). Our findings confirm the importance of soils in the global Hg cycling, as they exhibit significant Hg pools in horizons below the uppermost O and A horizons, preventing its mobilization to other environmental compartments.

为了研究影响汞含量，累积和垂直分布的土壤成分和过程，已对来自西南欧洲的两种森林土壤动物（ACB-I和ACB-II）进行了高分辨率土壤采样。总汞含量（THG）分别为28.0和23.6微克千克^-1在ACB-I和ACB-II的视野，则它们强烈在E视野降低，在这两个土壤（55.3和63.0微克公斤的BHS视野见顶^{- 1}）。在BwC视野中，THg再次下降至17.0和39.8μgkg ^-1。Bhs范围占存储的总汞量的46％和38％（分别为ACB-I和ACB-II）。主成分分析（PCA）和主成分回归（PCR），即使用提取的成分作为预测变量，可以区分构成每个视野中汞累积的土壤成分。获得的模型可准确预测累积的Hg（R ² = 0.845）通过四个主要成分（PC）。在A层中，Hg的分布受新鲜土壤有机质（PC4）的控制，而在E层中，所有PC的负值与缺少能够保留Hg的成分以及相应的非常低的THg浓度一致。Bhs视野中的最大THg含量与两种土壤中的活性Fe和Al化合物（PC1和PC2）以及次生结晶矿物（PC3）的最高峰一致。在最深层（Bw和BwC）中的THg分布似乎受到其他成岩过程的影响，而不是在剖面上部（A，E和Bhs层）中的那些。我们的发现证实了土壤在全球汞循环中的重要性，因为土壤在最高O和A层以下的层中显示出大量的Hg池，