Do tubificid worms influence organic matter processing and fate of pollutants in stormwater sediments deposited at the surface of infiltration systems?
The purpose of this study was to quantify the influences of tubificid worms on the biogeochemical functioning of an infiltration system impacted by a stormwater sediment deposit. Effects of worms with stormwater sediment deposit were compared with effects of worms with two other natural sediment deposits (one low and one rich-particulate organic matter deposits). We measured the effects of invertebrates on sediment reworking, organic matter processing, solute fluxes, microbial characteristics, and pollutant release from stormwater deposit to water. Our results showed that tubificid worms had slight effects on microbial activities in presence of the stormwater deposit whereas they significantly stimulated microbial activities in columns impacted by the other two deposits. High contents of labile organic matter contained in stormwater sediments probably led to very strong microbial activities that could not be easily stimulated by worm activities. In our experimental conditions, no significant influence of tubificid worms on the fate of pollutants (heavy metals and PAHs) contained in the stormwater deposit was measured. In conclusion, our study demonstrated that the organic matter characteristics of the stormwater sediments limited the efficiency of tubificid worms to stimulate organic matter mineralization in infiltration systems.
UMR-CNRS 5023, Laboratoire d'Ecologie des Hydrosystèmes Fluviaux, Université Claude, Bernard Lyon 1, 69622 Villeurbanne Cedex, France. nogaro@univ-lyon1.fr
Géraldine
G
Nogaro
Florian
F
Mermillod-Blondin
Bernard
B
Montuelle
Jean-Claude
JC
Boisson
Michel
M
Lafont
Bernadette
B
Volat
Janine
J
Gibert
D000818:Animals; D001673:Biodegradation, Environmental; D002947:Cities; D004784:Environmental Monitoring / Q000379:methods*; D005374:Filtration; D019015:Geologic Sediments / Q000032:analysis* / Q000382:microbiology; D006376:Helminths / Q000254:growth & development*; D006812:Humic Substances / Q000032:analysis*; D011891:Rain; D014871:Water Microbiology / Q000592:standards; D014874:Water Pollutants, Chemical / Q000032:analysis*
D006812:Humic Substances; D014874:Water Pollutants, Chemical