Serra A, Corcoll N, Guasch H
Department of Environmental Sciences, Institute of Aquatic Ecology, Faculty of Sciences, University of Girona (UdG), Campus Montilivi, 17071 Girona, Spain.
Chemosphere. 2009 Feb;74(5):633-41. doi: 10.1016/j.chemosphere.2008.10.036. Epub 2008 Dec 10.
Periphyton communities have a good bioaccumulation capacity and can be used to monitor metal pollution in fluvial ecosystems. Depending on the dose and exposure time, metals may produce changes in the structure and function of these communities, thus it is expected that the kinetics of metal accumulation and metal sensitivity will also be influenced by the exposure history. In this study, the effects of pulsed and continuous Cu exposures during the colonization of the communities were investigated under controlled conditions. This investigation includes the study of metal accumulation kinetics and the evaluation of community tolerance. Pulsed copper exposure did not affect the community structure but influenced the accumulation kinetics (decreasing intracellular copper uptake). On the other hand, continuous copper exposure caused a huge increase in metal content (both total and intracellular) and modified the structure of the community (increasing the percentage of cyanobacteria and diatom diversity). Both pulsed and continuous periphyton metal exposure may have negative repercussions for the fluvial ecosystem. While Cu pulsed exposure may be toxic to periphyton communities, continuous exposures may lead to community adaptation, which is often related to changes in species composition and higher metal contents being transferred to higher trophic levels of the stream food chain.
附生植物群落具有良好的生物累积能力，可用于监测河流生态系统中的金属污染。根据剂量和暴露时间的不同，金属可能会使这些群落的结构和功能发生变化，因此预计金属累积动力学和金属敏感性也会受到暴露历史的影响。在本研究中，在受控条件下研究了群落定殖期间脉冲式和持续性铜暴露的影响。该研究包括金属累积动力学研究和群落耐受性评估。脉冲式铜暴露未影响群落结构，但影响了累积动力学（细胞内铜摄取减少）。另一方面，持续性铜暴露导致金属含量大幅增加（总含量和细胞内含量均增加），并改变了群落结构（蓝藻百分比增加和硅藻多样性增加）。脉冲式和持续性附生植物金属暴露都可能对河流生态系统产生负面影响。虽然铜脉冲式暴露可能对附生植物群落有毒，但持续性暴露可能导致群落适应，这通常与物种组成的变化以及更高的金属含量转移到河流食物链的更高营养级有关。
