Regnell Olof, Elert Mark, Höglund Lars Olof, Falk Anna Helena, Svensson Anders
Department of Biology, Aquatic Ecology, University of Lund, Sölvegatan 37, 223 62, Lund, Sweden,
Ambio. 2014 Nov;43(7):878-90. doi: 10.1007/s13280-013-0487-2. Epub 2014 Jan 14.
Methylation of mercury (Hg) to highly toxic methyl Hg (MeHg), a process known to occur when organic matter (OM) decomposition leads to anoxia, is considered a worldwide threat to aquatic ecosystems and human health. We measured temporal and spatial variations in sediment MeHg, total Hg (THg), and major elements in a freshwater lagoon in Sweden polluted with Hg-laden cellulose fibers. Fiber decomposition, confined to a narrow surface layer, resulted in loss of carbon (C), uptake of nitrogen (N), phosphorus (P), and sulfur (S), and increased MeHg levels. Notably, fiber decomposition and subsequent erosion of fiber residues will cause buried contaminants to gradually come closer to the sediment-water interface. At an adjacent site where decomposed fiber accumulated, there was a gain in C and a loss of S when MeHg increased. As evidenced by correlation patterns and vertical chemical profiles, reduced S may have fueled C-fixation and Hg methylation at this site.
汞（Hg）甲基化为剧毒的甲基汞（MeHg），这一过程在有机物质（OM）分解导致缺氧时会发生，被认为是对水生生态系统和人类健康的全球性威胁。我们测量了瑞典一个被含汞纤维素纤维污染的淡水泻湖中沉积物甲基汞、总汞（THg）和主要元素的时空变化。纤维分解局限于狭窄的表层，导致碳（C）损失、氮（N）、磷（P）和硫（S）吸收增加以及甲基汞水平升高。值得注意的是，纤维分解以及随后纤维残渣的侵蚀将导致埋藏的污染物逐渐靠近沉积物 - 水界面。在相邻的一个分解纤维堆积的地点，当甲基汞增加时，碳增加而硫减少。相关模式和垂直化学剖面表明，还原态的硫可能在该地点促进了碳固定和汞甲基化。
