当前位置: X-MOL 学术Environ. Sci. Technol. Lett. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Near-Decadal Oscillation of Water Levels and Mercury Bioaccumulation in the Laurentian Great Lakes Region
Environmental Science & Technology Letters ( IF 10.9 ) Pub Date : 2020-01-15 , DOI: 10.1021/acs.estlett.9b00772
C. J. Watras 1, 2 , H.-Y. Teng 3 , A. W. Latzka 4 , M. W. Meyer 5 , Z. Zhang 3
Affiliation  

Mercury (Hg) contamination in remote lakes stems from atmospheric Hg transport to surface waters and subsequent conversion by microbes to neurotoxic methylmercury (MeHg) that biomagnifies in pelagic food webs. Despite declines in anthropogenic Hg emissions and downward trends for Hg in precipitation, many fisheries remain contaminated in otherwise pristine regions. Here, we report that trends in bioaccumulation are confounded by a near-decadal oscillation of the water cycle that is connected to large-scale atmospheric circulation patterns. In hundreds of lakes within the upper Laurentian Great Lakes region, mercury levels in pelagic fish and piscivorous birds oscillate in phase with near-decadal changes in water level, independent of atmospheric Hg loading. Geochemical data suggest that the cause is variation in the microbial production of MeHg as littoral sediments dry out and reflood. A recently amplified oscillation of the water cycle points to more intense episodes of fish contamination as the climate warms, further obscuring the benefit of reduced Hg emissions.

中文翻译:

Laurentian大湖地区水位和汞生物富集的近十年振荡

偏远湖泊中的汞(Hg)污染源于大气中的Hg迁移至地表水,以及微生物随后转化为在中上层食物网中生物放大的神经毒性甲基汞(MeHg)。尽管人为的汞排放量下降并且汞的降水量呈下降趋势,但在其他原始地区,许多渔业仍然受到污染。在这里,我们报告生物蓄积趋势是由与大型大气环流模式相关的水循环近十年的振荡所混淆。在劳伦山脉大湖区上游的数百个湖泊中,远洋鱼类和食肉鸟类的汞含量与水位几乎十年变化同步地振荡,而与大气中的汞负荷无关。地球化学数据表明,原因是沿海沿海沉积物变干并发生回潮,导致甲基汞的微生物产生变化。最近一次水循环振荡加剧,表明随着气候变暖,鱼类污染更加严重,这进一步模糊了减少汞排放的益处。
更新日期:2020-01-15
down
wechat
bug