Department of Life Sciences, University of Trieste, via Giorgieri 10, 34127, Trieste, Italy.
The Veterinary Medical Research Institute for Piemonte, Liguria and Valle d'Aosta, Via Bologna 148, 10154, Torino, Italy.
Environ Sci Pollut Res Int. 2020 Feb;27(6):5958-5970. doi: 10.1007/s11356-019-07325-x. Epub 2019 Dec 20.
Alpine lakes are extreme ecosystems located in remote areas and populated by few but well-adapted species. Because of their remote location, they are often considered pristine, unpolluted ecosystems. Since the 1980s, however, they have been affected by global anthropogenic impacts. Macrobenthic invertebrates play a pivotal role in these ecosystems and can be used as bioindicators also for monitoring the accumulation of trace elements. We characterized the macrobenthic invertebrates community of Balma Lake (Cottian Alps, Northwest Italy) and Dimon Lake (Carnic Alps, Northeast Italy) in summer and autumn and measured the levels of nine trace elements (As, Cd, Cr, Cu, Fe, Ni, Pb, Se, Zn) in the most abundant taxa (Chironomidae and Oligochaeta in both lakes and Hirudinea in Dimon Lake) in both seasons. The highest levels of trace elements were recorded for Fe, Cu, and Zn according to their environmental availability and their function as essential elements. The total amount of trace elements was highest for the Chironomidae from both lakes compared to the other two taxa. As, Cd, Pb, and Zn were measured in sediment to calculate bioaccumulation factor (BAF) values. The amount of elements in sediment and macrobenthic invertebrates was higher for Dimon Lake, suggesting a greater flux via precipitation of contaminants from the lowland. The BAF values were decreased with increasing trace elements concentration in sediment, indicating mechanisms of elements excretion in biota where the environment is contaminated. This study is the first to report on the use of macrobenthic invertebrates to monitor trace elements in Alpine lakes.
高山湖泊是位于偏远地区的极端生态系统，仅有少数适应能力强的物种在此栖息。由于地理位置偏远，这些湖泊通常被认为是原始的、未受污染的生态系统。然而，自 20 世纪 80 年代以来，它们受到了全球人为活动的影响。底栖无脊椎动物在这些生态系统中起着关键作用，它们也可以作为生物指标来监测痕量元素的积累。本研究于夏季和秋季对巴尔马湖（科蒂安阿尔卑斯山，意大利西北部）和迪蒙湖（卡尼阿尔卑斯山，意大利东北部）的底栖无脊椎动物群落进行了描述，并测量了两个湖泊中的优势类群（摇蚊科和寡毛纲）和迪蒙湖中的蛭纲在两个季节中的 9 种痕量元素（As、Cd、Cr、Cu、Fe、Ni、Pb、Se、Zn）的含量。根据痕量元素的环境可利用性及其作为必需元素的功能，Fe、Cu 和 Zn 的含量最高。与其他两种类群相比，两个湖泊的摇蚊科的痕量元素总量最高。在沉积物中测定了 As、Cd、Pb 和 Zn 的含量，以计算生物累积因子（BAF）值。与其他两种类群相比，沉积物和底栖无脊椎动物中的元素含量在迪蒙湖更高，这表明污染物通过低地的沉降从低地输送到高山湖泊的通量更大。BAF 值随着沉积物中痕量元素浓度的增加而降低，表明生物群中存在元素排泄机制，环境受到了污染。本研究首次报告了利用底栖无脊椎动物监测高山湖泊中的痕量元素。
