Mercury (Hg) in the environment has been receiving considerable attention in recent years, but little is known about Hg accumulation in trees. We analyzed Hg in tree rings from four tree species at the Hubbard Brook Experimental Forest in New Hampshire to determine whether Hg concentrations are more influenced by soil Hg concentrations, which have been stable or increasing due to the cumulative retention of historical atmospheric Hg deposition, or by atmospheric Hg deposition, which has declined in recent decades. Declining concentrations from the top to the bottom of the bole (p < 0.001) and from older to newer tree rings (p = 0.001) suggest that foliar uptake of Hg is more important than root uptake. Ten sugar maple clones planted in six blocks at the Heiberg Forest in New York State showed significant genetic control of sap Hg concentration (p = 0.02), which was not related to soil Hg concentration differences across blocks. Clones could differ in stomatal uptake, root uptake, or translocation of Hg. Better understanding of the source of Hg in wood is needed to forecast future changes in Hg cycling in forested ecosystems.

中文翻译：

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了解树中汞的新方法：年轮中汞的径向和纵向模式以及枫树汁中汞的遗传控制

近年来，环境中的汞已受到相当大的关注，但是对于汞在树木中的积累知之甚少。我们分析了新罕布什尔州Hubbard Brook实验森林中四种树种的年轮中的Hg，以确定Hg浓度是否受土壤Hg浓度的影响更大，土壤Hg浓度由于历史大气Hg的累积保留而保持稳定或增加，或者大气中汞的沉积，最近几十年来有所下降。从顶部到底部（p  <0.001）和从老到新的年轮（p = 0.001）表明叶面汞的吸收比根部的吸收更重要。在纽约州海伯格森林的六个街区中种植的十个糖枫克隆显示出显着的树液汞浓度遗传控制（p  = 0.02），这与跨街区的土壤汞浓度差异无关。克隆的气孔吸收，根吸收或汞转运可能不同。需要更好地了解木材中汞的来源，以预测森林生态系统中汞循环的未来变化。