The interplay between total mercury, methylmercury and dissolved organic matter in fluvial systems: A latitudinal study across Europe
The interplay between total mercury, methylmercury and dissolved organic matter in fluvial systems: A latitudinal study across Europe
复制标题
DOI：
10.1016/j.watres.2018.06.064
复制
发表时间：
2018-11-01
期刊：
影响因子：
12.8
通讯作者：
Amouroux, David
中科院分区：
文献类型：
--
作者：
Bravo, Andrea G.;Kothawala, Dolly N.;Amouroux, David
需要进行大规模研究，以确定水生态系统中总汞(THG)和甲基汞(MeHg)浓度的驱动因素。试图将溶解有机物(DOM)与THG或MeHg水平联系起来的研究很少，而且受到地理条件的限制。此外，与湖泊相比，人们对河流和河流系统的研究还不够深入。因此，这项研究的目的是研究DOM浓度和组成、形态描述符、土地利用和水化学对欧洲29条河流中三氢汞和甲基汞浓度以及三汞作为甲基汞的百分比(%Me汞)的影响，这些河流横跨北纬41度到度。甲基汞浓度(7.8pg-159pg L-1)在不同系统之间存在非系统差异。DOM体积特征与THG和MeHg之间的关系表明，虽然土壤来源的DOM输入控制着THG的浓度，但原生DOM(水产的)和汞甲基化微生物(如硫酸盐)的电子受体的可用性决定了%MeHg和潜在的MeHg浓度。总体而言，这些结果突出了欧洲尺度上THG和甲基汞浓度的巨大空间变异性，并强调了DOM组成对河流系统汞循环的重要性。(C)2018爱思唯尔有限公司。保留所有权利。
Large-scale studies are needed to identify the drivers of total mercury (THg) and monomethyl-mercury (MeHg) concentrations in aquatic ecosystems. Studies attempting to link dissolved organic matter (DOM) to levels of THg or MeHg are few and geographically constrained. Additionally, stream and river systems have been understudied as compared to lakes. Hence, the aim of this study was to examine the influence of DOM concentration and composition, morphological descriptors, land uses and water chemistry on THg and MeHg concentrations and the percentage of THg as MeHg (%MeHg) in 29 streams across Europe spanning from 41 degrees N to 64 degrees N. THg concentrations (0.06-2.78 ng L-1) were highest in streams characterized by DOM with a high terrestrial soil signature and low nutrient content. MeHg concentrations (7.8-159 pg L-1) varied non-systematically across systems. Relationships between DOM bulk characteristics and THg and MeHg suggest that while soil derived DOM inputs control THg concentrations, autochthonous DOM (aquatically produced) and the availability of electron acceptors for Hg methylating microorganisms (e.g. sulfate) drive %MeHg and potentially MeHg concentration. Overall, these results highlight the large spatial variability in THg and MeHg concentrations at the European scale, and underscore the importance of DOM composition on mercury cycling in fluvial systems. (C) 2018 Elsevier Ltd. All rights reserved.