Abstract：
This study analyzes the distribution of nine potentially toxic trace elements (arsenic, antimony, bromine, cobalt, chromium, mercury, rubidium, selenium, and zinc) in sediments and plankton from two small mesotrophic lakes in a non-industrialized area impacted by the Caviahue-Copahue volcanic complex (CCVC). The two lakes have different plankton community structures and received different amounts of pyroclastic material after the last CCVC eruption. Trace element concentrations of surface sediments differed between lakes, according to the composition of the volcanic ashes deposited in the lakes. The size of organisms was the principal factor influencing the accumulation of most trace elements in plankton within each lake, being trace element concentrations generally higher in the microplankton than in the mesozooplankton. The planktonic biomass in the shallower lake was dominated by small algae and copepods, while mixotrophic ciliates and different-sized cladocerans dominated the deeper lake. These differences in the community structure and species composition influenced the trace element bioaccumulation, especially in microplankton, while habitat use and feeding strategies seem more relevant in mesozooplankton bioaccumulation. This work contributes to the scarce records of trace elements and their dynamics in plankton from freshwater ecosystems impacted by volcanic activity.
摘要：
本研究分析了9种潜在有毒微量元素(砷，锑,溴,钴,铬,水银,铷,硒,和锌）在受Caviahue-Copahue火山复合体（CCVC）影响的非工业化地区的两个小型中营养湖泊的沉积物和浮游生物中。这两个湖泊的浮游生物群落结构不同，并且在上次CCVC喷发后接收了不同数量的火山碎屑物质。湖泊之间表层沉积物的微量元素浓度不同，根据沉积在湖泊中的火山灰的组成。生物的大小是影响每个湖泊中浮游生物中大多数微量元素积累的主要因素，微浮游生物中的微量元素浓度通常高于中浮游生物。较浅的湖泊中的浮游生物量以小型藻类和co足类为主，而混合营养的纤毛虫和不同大小的锁骨则占据了更深的湖泊。群落结构和物种组成的这些差异影响了微量元素的生物富集，尤其是在微浮游生物中，而栖息地的利用和摄食策略似乎与中浮游动物的生物积累更相关。这项工作有助于减少受火山活动影响的淡水生态系统中浮游生物的微量元素及其动态。
