Dissolved and particulate trace metal and rare earth element (REE) concentrations during a mesocosm based phytoplankton bloom simulating intertidal coastal conditions@en

We analyzed concentrations of dissolved and particulate trace metals, including iron (Fe), manganese (Mn), vanadium (V), molybdenum (Mo), thallium (Tl), and rare earth elements (REE), during a mesocosm-based phytoplankton summer bloom mimicking the intertidal zone of the southern North Sea (Jade Bay). The studies aimed to identify key drivers controlling their biogeochemical cycling in dynamic, high-productivity coastal environments. Our results highlight the tidally influenced coastal zone as a critical interface that alters the behavior of supposedly conservative elements such as Mo and Tl (Mori et al., 2021) as well as natural and anthropogenic REE (incl., lanthanum, samarium, and gadolinium) (Mori et al., under review). Trace metal concentrations and shale-normalized REE patterns, determined by quadrupole inductively coupled plasma–mass spectrometry (ICP-MS) and inductively coupled plasma–optical emission spectrometry (ICP-OES), were combined with biogeochemical bulk parameters and pigment-based assessments of phytoplankton growth and community composition (Mustaffa et al., 2020). Trace metal and REE cycling were evaluated in relation to phytoplankton dynamics, particulate organic matter composition (C, N, P), dissolved organic carbon, total dissolved nitrogen, and macronutrient concentrations (nitrate, ammonium, silicate, and inorganic phosphate). The dataset was obtained during a Planktotron-based mesocosm experiment conducted within the framework of the Coastal Ocean Darkening project (Mustaffa et al., 2020).本研究在模拟北海南部亚德湾（Jade Bay）潮间带环境的中宇宙（mesocosm）体系夏季浮游植物藻华实验期间，对溶解态与颗粒态痕量金属（trace metals）——包括铁（Fe）、锰（Mn）、钒（V）、钼（Mo）、铊（Tl）以及稀土元素（rare earth elements, REE）——的浓度开展了分析测定。本研究旨在明确动态高生产力近岸环境中调控这些物质生物地球化学循环的关键驱动因子。研究结果表明，受潮汐影响的近岸海域是关键界面，可改变钼（Mo）、铊（Tl）等原本被认为是保守性元素的地球化学行为（Mori等，2021），同时也会影响自然源与人为源稀土元素（包括镧、钐与钆）的循环过程（Mori等，待刊）。本研究通过四极杆电感耦合等离子体质谱（quadrupole inductively coupled plasma–mass spectrometry, ICP-MS）与电感耦合等离子体光发射光谱法（inductively coupled plasma–optical emission spectrometry, ICP-OES）测定了痕量金属浓度与页岩标准化稀土元素配分模式，并结合生物地球化学整体参数以及基于色素分析的浮游植物生长与群落组成评估结果（Mustaffa等，2020）开展联合分析。本研究还结合浮游植物动态变化、颗粒有机质组成（C、N、P）、溶解有机碳、总溶解氮以及大量营养盐浓度（硝酸盐、铵盐、硅酸盐与无机磷酸盐），对痕量金属与稀土元素的循环过程进行了评估。本数据集源自「近岸海洋变暗（Coastal Ocean Darkening）」项目框架下开展的基于Planktotron系统的围隔实验（Mustaffa等，2020）。