Chl-a fluorescence parameters as biomarkers of metal toxicity in fluvial biofilms: an experimental study |
| |
Authors: | Natàlia Corcoll Berta Bonet Manel Leira Helena Guasch |
| |
Affiliation: | 1.Institute of Aquatic Ecology,University of Girona,Girona,Spain;2.Faculty of Sciences,University of A Coru?a,A Coru?a,Spain |
| |
Abstract: | A study was carried out to evaluate the sensitivity of different chlorophyll-a (chl-a) fluorescence parameters measured in freshwater biofilms as metal pollution biomarkers of short- and long-term metal exposures at environmentally realistic concentrations. A microcosm experiment was performed using indoor channels. Mature biofilms were exposed from hours to weeks to three different treatments: No-Metal, Zn (400 μg l−1); and Zn plus Cd (400 μg l−1 and 20 μg l−1, respectively). Metal concentration was based on a real case study: the Riou-Mort River (France). Biofilms exposed to Zn bioaccumulated similar Zn contents per dry weight to those exposed to the mixture (Zn plus Cd) causing a similar inhibition of the effective quantum yield (UpphitextM¢)(Upphi_{text{M}}^{prime}) during the first hours of exposure. A reduction of the algal biomass, a shift in the community composition (a high reduction of diatoms), a reduction of the maximal quantum yield (ΦM) and a strong reduction of non-photochemical quenching (NPQ) were observed from day 14 until the end of the experiment (35 days). The results indicate that the effects of the metal mixture present in the Riou-Mort on biofilms could be attributed to Zn toxicity. The use of a set of chl-a fluorescence measurements, including photochemical and NPQ parameters, are recommended as a reliable biomarker tool box to evaluate both short- and long-term effects of metals on biofilms containing oxygenic photoautotrophs, suggesting its use in field applications. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|