An experimental study on the mixing behavior of Ti, Zr, V and Mo in the Elbe, Rhine and Weser estuaries
An experimental study on the mixing behavior of Ti, Zr, V and Mo in the Elbe, Rhine and Weser estuaries
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DOI：
10.1016/j.ecss.2015.12.002
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发表时间：
2016-03
影响因子：
2.8
通讯作者：
Alexandre Schneider;A. Koschinsky;Joseph Kiprotich-;S. Poehle;P. C. Nascimento
中科院分区：
文献类型：
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作者：
Alexandre Schneider;A. Koschinsky;Joseph Kiprotich-;S. Poehle;P. C. Nascimento
河口是陆地与海洋的重要界面，通过河流进入海洋的微量金属元素常常沿着淡水与海水的混合梯度发生显著的改变。在本研究中，我们已经进行了混合实验，从莱茵河，易北河和威悉河的河水和海水从北海的目的是获得更多的洞察行为的钛（Ti），锆（Zr），钒（V）和钼（Mo）和它们之间的分布溶解和颗粒形式在河口混合。人们对它们在河口的浓度变化知之甚少，这些金属越来越多地进入河流和海洋，因为它们在工业活动中被用作所谓的高科技金属。在受控条件下的这种实验室实验允许系统地研究与混合比相关的化学变化，而不依赖于自然系统中发生的进一步影响因素。吸附溶出伏安法用于分析测定的四种金属。尽管我们的数据在很大程度上证实了Ti和Zr的强粒子反应行为和Mo的大部分保守行为，但我们的混合实验揭示了与此行为的部分偏差。钒大多不遵循严格的保守的混合趋势，但显示小的广告和解吸作用沿着盐度样带。此外，Mo显示出在中等盐度下与保守混合的一些偏差。在约50：50的河流：海水混合物中溶解的钛和锆的富集与最近发表的类似的实地研究数据一致，似乎是一个系统的影响，可能与颗粒表面的电荷转移或溶解的金属形态的变化。所观察到的效果部分不同的过滤和非过滤的河水样品，特别是Ti和Zr的实验，突出了河流颗粒物的作用，在河口溶解的微量金属通量的修改。
Estuaries are important interfaces between land and ocean, in which the input of trace metals into the ocean via the rivers is often significantly modified along the mixing gradient between freshwater and seawater. In the present study we have carried out mixing experiments using river water from the Rhine, the Elbe and the Weser and seawater from the North Sea with the aim of gaining more insights into the behavior of titanium (Ti), zirconium (Zr), vanadium (V) and molybdenum (Mo) and their distribution between dissolved and particulate forms during mixing in the estuaries. Little is known about the modification of their concentrations in estuaries and these metals increasingly enter the rivers and the ocean due to their application as so-called high-tech metals in industrial activities. Such laboratory experiments at controlled conditions allow the systematic investigation of chemical changes related to the mixing ratios, independent of further influence factors occurring in natural systems. Adsorptive stripping voltammetry was used for the analytical determination of the four metals. Although our data largely confirmed a strong particle-reactive behavior of Ti and Zr and a mostly conservative behavior of Mo, our mixing experiments revealed partial deviation from this behavior. Vanadium mostly does not follow a strict conservative mixing trend but shows both small ad- and desorption effects along the salinity transect. Also Mo shows some deviations from conservative mixing at mid-salinities. The enrichment of dissolved Ti and Zr at about 50:50 river: seawater mixtures agrees with recently published data of similar field studies and appears to be a systematic effect possibly related to charge transitions on particle surfaces or change of the dissolved metal speciation. The observed effects partly differed in experiments with filtered and non-filtered river water samples, especially for Ti and Zr, highlighting the role of riverine particulate matter for the modification of dissolved trace metal fluxes in estuaries.