Division for Marine and Environmental Research, Ruđer Bošković Institute, P.O. Box 180, HR-10002 Zagreb, Croatia.
Division for Marine and Environmental Research, Ruđer Bošković Institute, P.O. Box 180, HR-10002 Zagreb, Croatia.
Sci Total Environ. 2015 Apr 1;511:423-34. doi: 10.1016/j.scitotenv.2014.12.076. Epub 2015 Jan 5.
The distribution and speciation of elements along a stream subjected to neutralised acid mine drainage (NAMD) effluent waters (Mátra Mountain, Hungary; Toka stream) were studied by a multi-methodological approach: dissolved and particulate fractions of elements were determined by HR-ICPMS, whereas speciation was carried out by DGT, supported by speciation modelling performed by Visual MINTEQ. Before the NAMD discharge, the Toka is considered as a pristine stream, with averages of dissolved concentrations of elements lower than world averages. A considerable increase of element concentrations caused by effluent water inflow is followed by a sharp or gradual concentration decrease. A large difference between total and dissolved concentrations was found for Fe, Al, Pb, Cu, Zn and As in effluent water and at the first downstream site, with high correlation factors between elements in particulate fraction, indicating their common behaviour, governed by the formation of ferri(hydr)oxides (co)precipitates. In-situ speciation by the DGT technique revealed that Zn, Cd, Ni, Co, Mn and U were predominantly present as a labile, potentially bioavailable fraction (>90%). The formation of strong complexes with dissolved organic matter (DOM) resulted in a relatively low DGT-labile concentration of Cu (42%), while low DGT-labile concentrations of Fe (5%) and Pb (12%) were presumably caused by their existence in colloidal (particulate) fraction which is not accessible to DGT. Except for Fe and Pb, a very good agreement between DGT-labile concentrations and those predicted by the applied speciation model was obtained, with an average correlation factor of 0.96. This study showed that the in-situ DGT technique in combination with model-predicted speciation and classical analysis of samples could provide a reasonable set of data for the assessment of the water quality status (WQS), as well as for the more general study of overall behaviour of the elements in natural waters subjected to high element loads.
受中和酸性矿山排水（NAMD）废水（匈牙利马特拉山；托卡河）影响的溪流中元素的分布和形态研究采用了多方法学方法：通过高分辨率电感耦合等离子体质谱法（HR-ICPMS）测定元素的溶解态和颗粒态分数，而通过 DGT 进行形态分析，并通过 Visual MINTEQ 进行形态模拟支持。在 NAMD 排放之前，托卡河被认为是一条原始溪流，其元素的溶解浓度平均值低于世界平均值。大量由于废水流入而导致的元素浓度增加，随后是浓度的急剧或逐渐下降。在废水和第一个下游点，发现总浓度和溶解浓度之间存在很大差异，颗粒态分数中元素之间存在很高的相关系数，表明它们的共同行为受铁（氢）氧化物（共）沉淀的形成控制。通过 DGT 技术进行的原位形态分析表明，Zn、Cd、Ni、Co、Mn 和 U 主要以不稳定、潜在生物可利用的形态存在（>90%）。与溶解有机物（DOM）形成强络合物导致 Cu 的 DGT 不稳定浓度相对较低（42%），而 Fe（5%）和 Pb（12%）的 DGT 不稳定浓度较低，可能是因为它们存在于胶体（颗粒）分数中，而 DGT 无法接触到。除 Fe 和 Pb 外，DGT 不稳定浓度与应用形态模型预测的浓度之间非常吻合，平均相关系数为 0.96。这项研究表明，原位 DGT 技术与模型预测的形态和样品的经典分析相结合，可以为评估水质状况（WQS）提供合理的数据，以及更广泛地研究受高元素负荷影响的天然水中元素的整体行为。
