Millennium analysis of mercury content in the North Atlantic sediments during the late Pliocene

澄清了北大西洋沉积物中汞含量在过去100万年和2550ka至2550ka之间的变化，其变化周期分别为100000年和41000年，以及3000年和5000年。冰期沉积物汞含量随着冰筏碎屑(IRD)的增加而增加，与总有机碳含量呈正相关，与碳同位素比值和表层微型浮游植物绝对丰度呈负相关。这些观察表明，流向该海域的含汞和含IRD的冰山在冰川时期融化，增加的光水汞被并入到下光带深水浮游植物产生的有机质中。沉积物汞含量可以作为北半球浮冰在轨道和千年尺度上扩大和减少的新的化学指标。

It was clarified that mercury contents in the North Atlantic sediments over the last 1,000,000 years and during a period between 2500 ka and 2550 ka changed with distinct periods of 100,000 and 41,000 years, and 3000 and 5000 years, respectively. The sediment Hg content increased during glacial periods with the increase of ice-rafted debris (IRD), correlating positively with total organic carbon content and inversely with its carbon isotopic ratio and the absolute abundance of surface-dwelling nannoplankton species. These observations suggest that Hg- and IRD-bearing icebergs flowed out to this sea area melted during glacial periods and the increased Hg of photic water is incorporated into the organic matter produced by deep-dwelling phytoplankton in the lower photic zone. Sediment Hg content can be used as a new chemical indicator of enlargement and reduction of ice floes in the northern hemisphere in both orbital and millennium scales