Biomonitoring of Epilobium hirsutum L. Health Status to Assess Water Ecotoxicity in Constructed Wetlands Treating Mixtures of Contaminants

Abstract

For the treatment of wastewater containing organic pollutants and metals in constructed wetlands (CWs), phytoindicators may help in guiding management practices for plants and optimizing phytoremediation processes. Hairy willow-herb (Epilobium hirsutum L.) is a fast growing species commonly found in European CWs that could constitute a suitable phytoindicator of metal toxicity. E. hirsutum was exposed for 113 days in microcosm CWs, to a metal and metalloid mixture (MPM, containing Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sn, Zn), an organic pollutant mixture (OPM, containing hydrocarbonsC10-C40, phenanthrene, pyrene, anionic detergent LAS) and an organic pollutant and metal and metalloid mixture (OMPM), separately and at concentration levels mimicking levels of industrial effluents. Analyses of metal and As concentrations in biomass, and different biometric and physiological measurements were performed. Results showed that metal uptake patterns were affected by the type of pollutant mixture, resulting in variation of toxicity symptoms in OPEN ACCESSWater 2015, 7 698 E. hirsutum plants. Some of them appeared to be similar under MPM and OMPM conditions (leaf chlorosis and tip-burning, decrease of green leaf proportion), while others were characteristic of each pollutant mixture (MPM: Decrease of water content, increase of phenol content; OMPM: reduction of limb length, inhibition of vegetative reproduction, increase of chlorophyll content and Nitrogen balance index). Results emphasize the potential of E. hirsutum as a bioindicator species to be used in European CWs treating water with metal, metalloid and organic pollutants.

Evaluation of an integrated constructed wetland to manage pig manure under Mediterranean climate

“…To go further, complementary studies of biometrics parameters monitored during this experiment (width, length, and number of leaves, maximum aerial length etc.) and physiological parameters (chlorophyll, anthocyan, and flavonol concentrations and stress proteins) will permit to underscore other phytotoxicity symptoms as growth inhibition or loss of the original sheet (Finlayson et al 1987;Baldwin and Clarke 2002;Guittonny-Philippe et al 2015). These further studies will permit to select between the tolerant species highlighted in this studies, even if they do not present significant mortality rate, those which present less symptoms in order to optimize plants growth and maximize their role in pig wastewater treatment (Baldwin and Clarke 2002).…”