Enhancing ecosystem services of contaminated soil
Résumé
Contaminated soils have lost some ecological functions and ecosystem services (Hooper et al., 2015). Remediating contaminated sites could then help to restore lost ecological functions and ecosystem services. The test has been made by using phytoextraction, a nature-based solution that aims at remediating trace element (TE) in contaminated areas using plants and, sometimes, chelatants. Metal removal is obtained by decreasing the availability of TE in contaminated areas, TE being transferred to the harvestable plant parts. This emerging technology has progressively shifted to phytomanagement, which takes into account the value created by the biomass produced on contaminated area. In case of phytoextraction, the metal-enriched biomass can produce an economic revenue from metal recovery, being then a new source of raw material for further technological processes. The PHYTOAGGLO project was set up in 2013 in an urban area contaminated by TE (Zn, Cd, Pb, Cu) impacted by diverse past industrial activities. In collaboration with the conurbation of Creil city (60 km in the North of Paris), plants (Arabidopsis halleri, an Cd/Zn hyperaccumulating species and Salix viminalis, a fast-growing metal accumulator willow tree) were selected to regenerate the urban area and improve the well-being of citizens, to remove contaminants, to restore ecosystem and to participate to the provisioning of non-food and sustainable products. The results of 3- years monitoring will be presented and discussed in regards to the various ecosystem services provided by this nature-based solution.