Dipartimento di Chimica e Fisica della Terra ed Applicazioni alle Georisorse e ai Rischi Naturali (CFTA), Università degli Studi di Palermo, via Archirafi 36, 90123 Palermo, Italy.
Chemosphere. 2009 Oct;77(6):778-84. doi: 10.1016/j.chemosphere.2009.08.021. Epub 2009 Sep 6.
The distribution of rare earth elements and yttrium (REEs+Y) has been investigated in box-core sediments recovered from four stations in the Sicilian coastal zone seawards of Augusta, one of the most industrialized and contaminated areas in the Mediterranean region. Shale-like REE patterns and low Y/Ho ratios (close to the chondritic ratio) suggest a dominant terrigenous (geogenic) source for REE. Slight enrichment of LREE over the HREE is interpreted as due to preferential adsorptive transfer of LREE from seawater to sediment particles. Samples from offshore cores exhibit slightly positive Gd and negative Ce anomalies. It is here hypothesized that main drivers of anthropogenic Gd flux towards the offshore are dredged contaminated materials that, recovered from the Augusta Bay, have been repeatedly discharged offshore. Consistent with the redox-chemistry of Ce, these anomalous sedimentary inputs induce a decrease of O(2) concentration in the sediment, which in turn triggers Ce regeneration.
对从奥古斯塔（撒丁岛沿海城市，也是地中海地区工业化和污染最严重的地区之一）附近的四个站位采集的箱芯沉积物中的稀土元素和钇（REEs+Y）的分布进行了研究。似页岩的 REE 模式和低 Y/Ho 比值（接近球粒陨石比值）表明 REE 的主要来源是陆源（地质成因）。LREE 相对于 HREE 的轻微富集被解释为由于 LREE 优先从海水中吸附转移到沉积物颗粒上。来自远海岩芯的样品显示出略微正的 Gd 和负的 Ce 异常。据推测，向远海输送人为 Gd 通量的主要驱动力是从奥古斯塔湾疏浚出来的受污染物质，这些物质已经被多次排放到远海。与 Ce 的氧化还原化学性质一致，这些异常的沉积输入导致沉积物中 O(2)浓度降低，从而引发 Ce 的再生。
