Studies of mercury (Hg) in the Mediterranean Sea have focused on pollution sources, air-sea mercury exchange, abiotic mercury cycling, and seafood. Much less is known about methylmercury (MeHg) concentrations in the lower food web. Zooplankton and small fish were sampled from the neuston layer at both coastal and open sea stations in the Mediterranean Sea during three cruise campaigns undertaken in the fall of 2011 and the summers of 2012 and 2013. Zooplankton and small fish were sorted by morphospecies, and the most abundant taxa (e.g. euphausiids, isopods, hyperiid amphipods) analyzed for methylmercury (MeHg) concentration. Unfiltered water samples were taken during the 2011 and 2012 cruises and analyzed for MeHg concentration. Multiple taxa suggested elevated MeHg concentrations in the Tyrrhenian and Balearic Seas in comparison with more eastern and western stations in the Mediterranean Sea. Spatial variation in zooplankton MeHg concentration is positively correlated with single time point whole water MeHg concentration for euphausiids and mysids and negatively correlated with maximum chlorophyll a concentration for euphausiids, mysids, and "smelt" fish. Taxonomic variation in MeHg concentration appears driven by taxonomic grouping and feeding mode. Euphausiids, due to their abundance, relative larger size, importance as a food source for other fauna, and observed relationship with surface water MeHg are a good candidate biotic group to evaluate for use in monitoring the bioavailability of MeHg for trophic transfer in the Mediterranean and potentially globally.

中文翻译：

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地中海低营养水平动物群中汞浓度的空间和分类学变化。

地中海中汞（Hg）的研究集中于污染源，海气中的汞交换，非生物汞循环和海鲜。对下部食物网中甲基汞（MeHg）浓度的了解很少。在2011年秋季以及2012年和2013年夏季进行的三次巡游活动中，从地中海沿岸和公海站的神经元层采样了浮游动物和小鱼。对浮游动物和小鱼按形态学进行了分类，对甲基汞（MeHg）浓度进行了分析的最丰富的分类单元（例如，古怪足类，异足类，双足类两足动物）。在2011年和2012年的航行中采集了未经过滤的水样，并分析了MeHg浓度。与地中海中更多的东部和西部站点相比，多个分类单元表明在第勒尼安海和巴利阿里海中的MeHg浓度升高。浮游生物MeHg浓度的空间变化与虾up和虾类的单一时间点全水MeHg浓度呈正相关，而与虾up，虾类和“冶炼”鱼的最大叶绿素a浓度呈负相关。MeHg浓度的分类学变化似乎是由分类学分组和进食模式驱动的。虾类由于其丰富，相对较大的大小，作为其他动物的食物来源的重要性，