Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Fisheries and Oceans Canada, St. John's, Newfoundland and Labrador, A1C 5X1, Canada.
Sci Total Environ. 2015 Mar 15;509-510:165-74. doi: 10.1016/j.scitotenv.2013.11.147. Epub 2013 Dec 27.
Anadromous and non-anadromous Arctic charr (Salvelinus alpinus) from multiple sample sites in Labrador, Canada were used to investigate possible differences in total mercury concentration ([THg]) between 1977-78 and 2007-09. The mean [THg] of anadromous Arctic charr was 0.03 μg/g wet weight (ww) in 1977-78 and 0.04 μg/g ww in 2007-09, while mean concentrations in non-anadromous conspecifics were 0.18 μg/g ww in 1977-78 and 0.14 μg/g ww in 2007-09. After correcting for the effects of fish age and fork-length, there was no widespread difference in the mean [THg] of anadromous or non-anadromous fish between the two time periods. However, at individual sites sampled during both time periods, [THg] increased, decreased, or did not change. The mean age of sampled fish declined from 9.0 years in 1977-78 to 8.2 years in 2007-09 for anadromous fish, and from 11.7 years to 10.5 years in non-anadromous Arctic charr. Similarly, mean fork-lengths decreased from 450 mm to 417 mm in anadromous and from 402 mm to 335 mm in non-anadromous fish between 1977-78 and 2007-09. The mean annual temperature at four Labrador weather stations increased by 1.6°C to 2.9°C between the two sampling periods. The lack of an overall trend in anadromous or non-anadromous Arctic charr [THg] despite warming temperatures that favour increased mercury methylation suggests that regional changes in climate-driven factors have had limited impacts on mercury exposure in Labrador freshwater or marine fish.
来自加拿大拉布拉多多个采样点的溯河洄游和非溯河洄游北极茴鱼（Salvelinus alpinus）被用于研究 1977-78 年和 2007-09 年期间总汞浓度（[THg]）之间可能存在的差异。1977-78 年溯河洄游北极茴鱼的平均[THg]为 0.03μg/g 湿重（ww），2007-09 年为 0.04μg/g ww，而非溯河洄游同种鱼类的平均浓度分别为 0.18μg/g ww 和 0.14μg/g ww。在考虑了鱼类年龄和叉长的影响后，两个时期溯河洄游和非溯河洄游鱼类的平均[THg]没有普遍差异。然而，在两个时期都采样的个别地点，[THg]增加、减少或没有变化。采样鱼的平均年龄从 1977-78 年的 9.0 岁下降到 2007-09 年的 8.2 岁，溯河洄游鱼类，而非溯河洄游北极茴鱼的平均叉长从 450mm 减少到 417mm，从 402mm 减少到 335mm。1977-78 年至 2007-09 年期间，拉布拉多四个气象站的年平均气温上升了 1.6°C 至 2.9°C。尽管气温升高有利于增加汞的甲基化，但溯河洄游和非溯河洄游北极茴鱼[THg]并没有整体呈上升趋势，这表明气候驱动因素的区域变化对拉布拉多淡水或海洋鱼类的汞暴露影响有限。
