Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON, Canada.
Sci Total Environ. 2010 Mar 15;408(8):1858-67. doi: 10.1016/j.scitotenv.2010.01.014. Epub 2010 Feb 11.
At Cape Vera (Devon Island, Nunavut, Canada), a seabird colony of northern fulmars (Fulmarus glacialis) congregates and releases nutrients through the deposition of guano to the coastal terrestrial environment, thus creating nutrient-fertilized habitats important to insects, birds, and mammals. Here we determined whether mercury was similarly enriched in various terrestrial food web components in this High Arctic coastal ecosystem due to seabird inputs. Stable isotopes (delta(15)N, delta(13)C) were used to identify trophic linkages and possible routes of contaminant transfer in the food web. Values of delta(15)N were significantly higher in lichens and certain plants collected closer to the bird colony, demonstrating a gradient of seabird influence, and were higher at Cape Vera than our reference site at Cape Herschel, on eastern Ellesmere Island, an area relatively unaffected by seabirds. In contrast, delta(13)C showed little variation among terrestrial species, suggesting minimal influence by seabirds. Concentrations of total mercury (THg) in primary producers and phyto/zooplankton were not significantly correlated with distance from the seabird colony or delta(15)N values, and were similar to other taxa from the High Arctic. Our results provide novel data on THg in several Arctic taxa where concentrations have not been reported previously. Moreover, the analyses indicate that delta(15)N is significantly enriched in the adjacent environment by guano fertilization, but our study was unable to show an enrichment of THg and delta(13)C in the terrestrial food web near the seabird colony.
在弗拉角（加拿大努纳武特地区德文岛），北方管鼻藿（北方管鼻燕）的海鸟聚居地通过鸟粪的沉积向沿海陆地环境释放养分，从而创造了养分丰富的栖息地，对昆虫、鸟类和哺乳动物都很重要。在这里，我们确定了由于海鸟的输入，汞是否也同样在这个高北极沿海生态系统的各种陆地食物网成分中得到了富集。稳定同位素（δ15N、δ13C）被用来确定食物网中的营养联系和可能的污染物转移途径。收集的地衣和某些植物的δ15N 值在靠近鸟类聚居地的地方明显较高，这表明存在海鸟影响的梯度，而且在弗拉角的δ15N 值高于我们在埃尔斯米尔岛东部的赫歇尔角的参考点，赫歇尔角是一个相对不受海鸟影响的地区。相比之下，δ13C 在陆地物种之间变化不大，这表明海鸟的影响很小。初级生产者和浮游植物/浮游动物中的总汞（THg）浓度与距海鸟聚居地的距离或δ15N 值没有显著相关性，与高北极地区的其他类群相似。我们的研究结果提供了关于高北极地区几个分类群中 THg 的新数据，这些数据以前没有报道过。此外，分析表明，由于鸟粪的施肥作用，相邻环境中的 δ15N 显著富集，但我们的研究未能表明海鸟聚居地附近陆地食物网中 THg 和 δ13C 的富集。
