Hoang T. K., Probst A., Orange Didier, Gilbert F., Elger A., Kallerhoff J., Laurent F., Bassil S., Duong T. T., Gerino M. (2018). Bioturbation effects on bioaccumulation of cadmium in the wetland plant Typha latifolia : a nature-based experiment. Science of the Total Environment, 618, p. 1284-1297. ISSN 0048-9697.
Titre du document
Bioturbation effects on bioaccumulation of cadmium in the wetland plant Typha latifolia : a nature-based experiment
Hoang T. K., Probst A., Orange Didier, Gilbert F., Elger A., Kallerhoff J., Laurent F., Bassil S., Duong T. T., Gerino M.
Source
Science of the Total Environment, 2018,
618, p. 1284-1297 ISSN 0048-9697
The development of efficient bioremediation techniques to reduce aquatic pollutant load in natural sediment is one of the current challenges in ecological engineering. A nature-based solution for metal bioremediation is proposed through a combination of bioturbation and phytoremediation processes in experimental indoormicrocosms. The invertebrates Tubifex tubifex (Oligochaeta Tubificidae) was used as an active ecological engineer for bioturbation enhancement. The riparian plant species Typha latifolia was selected for its efficiency in phytoaccumulating pollutants from sediment. Phytoremediation efficiency was estimated by using cadmium as a conservative pollutant known to bioaccumulate in plants, and initially introduced in the overlying water (20 mu g Cd/L of cadmium nitrate Cd(NO3)(2)center dot 4H(2)O). Biological sediment reworking by invertebrates' activity was quantified using luminophores (inert particulates). Our results showed that bioturbation caused by tubificid worms' activity followed the bio-conveying transport model with a downward vertical velocity (V) of luminophores ranging from 16.7 +/- 4.5 to 18.5 +/- 3.9 cm.year(-1). The biotransport changed the granulometric properties of the surface sediments, and this natural process was still efficient under cadmium contamination. The highest value of Cd enrichment coefficient for plant roots was observed in subsurface sediment layer (below 1 cm to 5 cm depth) with tubificids addition. We demonstrated that biotransport changed the distribution of cadmium across the sediment column as well as it enhanced the pumping of this metal from the surface to the anoxic sediment layers, thereby increasing the bioaccumulation of cadmium in the root system of Typha latifolia. This therefore highlights the potential of bioturbation as a tool to be considered in future as integrated bioremediation strategies of metallic polluted sediment in aquatic ecosystems.
Plan de classement
Pollution [038]
;
Géologie et formations superficielles [064]
;
Sciences du monde végétal [076]
