Department of Biology, Norwegian University of Science and Technology, Høgskoleringen 5, 7491 Trondheim, Norway; Aquatic Ecology, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany.
CIBIO/InBio, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Campus de Vairão, Vila do Conde, Rua Padre Armando Quintas 7, 4485-661 Vairão, Portugal.
Sci Total Environ. 2019 Aug 1;676:746-755. doi: 10.1016/j.scitotenv.2019.04.217. Epub 2019 Apr 19.
Understanding the levels and drivers of contamination in top predators is important for their conservation and eventual use as sentinels in environmental monitoring. Therefore, metals and trace elements were analyzed in feathers of Bonelli's eagles (Aquila fasciata) from southern Portugal in 2007-2013, where they are believed to be exposed to a wide range of contamination sources such as agricultural land uses, urban areas, active and abandoned mines and a coal-fired power plant. We focused on concentrations of aluminum (Al), arsenic (As), copper (Cu), chromium (Cr), mercury (Hg), lead (Pb), selenium (Se) and zinc (Zn), as these contaminants are potentially associated with those sources and are known to pose a risk for terrestrial vertebrates. Stable isotope values of nitrogen (δN: N/N), carbon (δC: C/C) and sulphur (δS: S/S) were used as dietary proxies to control for potential effects of prey composition on the contamination pattern. The spatial distribution of potential contamination sources was quantified using geographic information systems. Concentrations of Hg in the southern part of the study area were above a reported toxicity threshold for raptors, particularly in territories closer to a coal-fired power plant at Sines, showing that contamination persisted after a previous assessment conducted in the 1990s. Hg and Se levels were positively correlated with δN, which indicates biomagnification. Concentrations of As, Cr, Cu, Pb and Zn were generally low and unrelated to mining- or industrial activities, indicating low environmental background concentrations. Al was found at higher concentrations in the southernmost areas of Portugal, but this pattern might be related to external soil contamination on feathers. Overall, this study indicates that, among all elements studied, Hg seems to be the most important contaminant for Bonelli's eagles in southern Portugal, likely due to the power plant emissions and biomagnification of Hg in terrestrial food webs.
了解顶级捕食者体内的污染水平和驱动因素对于它们的保护以及最终将其作为环境监测的哨兵物种具有重要意义。因此，在 2007 年至 2013 年间，对来自葡萄牙南部的 Bonelli 鹰（Aquila fasciata）的羽毛进行了金属和微量元素分析，据信这些鹰在这些地区会暴露于广泛的污染来源，如农业用地、城市地区、活跃和废弃的矿山以及燃煤电厂。我们重点关注了铝（Al）、砷（As）、铜（Cu）、铬（Cr）、汞（Hg）、铅（Pb）、硒（Se）和锌（Zn）的浓度，因为这些污染物可能与这些来源有关，并且已知会对陆地脊椎动物构成风险。氮（δN：N/N）、碳（δC：C/C）和硫（δS：S/S）的稳定同位素值被用作饮食代理，以控制猎物组成对污染模式的潜在影响。利用地理信息系统量化了潜在污染来源的空间分布。研究区域南部的 Hg 浓度高于先前报道的猛禽毒性阈值，尤其是在距离锡尼斯燃煤电厂较近的地区，这表明在 20 世纪 90 年代进行的先前评估之后，污染仍在持续。Hg 和 Se 水平与 δN 呈正相关，这表明生物放大作用。As、Cr、Cu、Pb 和 Zn 的浓度通常较低，与采矿或工业活动无关，表明环境背景浓度较低。在葡萄牙最南端地区发现了更高浓度的 Al，但这种模式可能与羽毛上的外部土壤污染有关。总体而言，这项研究表明，在所研究的所有元素中，Hg 似乎是葡萄牙南部 Bonelli 鹰的最重要污染物，这可能是由于电厂排放和 Hg 在陆地食物网中的生物放大作用所致。
