Does fresh organic matter addition to an industrial soil have an impact on soil structure and on PAH concentration, repartition and availability?
Résumé
A simulation of 10 years of maize culture was performed by incubation of industrial soil
highly contaminated by polycyclic aromatic hydrocarbons (PAH) and containing exclusively
anthropogenic organic matter (OM) mixed with maize residue. The aim was to evaluate the
impact of the fresh OM incorporation on the soil structure and consequently on the
contaminants repartition, concentration and availability. Water granulodensimetric
fractionation was carried out to isolate five water stable material fractions (coarse and fine
sands, coarse and fine silts and clays). The evolution of the added maize repartition in these
fractions was followed using δ13C. Total and available PAH content in the bulk soil as well as
in the different fractions were determined by solvent and Tenax® resin extraction
respectively. The monitoring of soil structure showed an aggregation process in the amended
soil after 3 months of incubation probably due to the promoting of microbial activity. Among
the different fractions, fine silts distinguished themselves by enrichment in total organic
carbon and in δ13C due to the added carbon. However, the results showed no significant
impact on pollution, which remained stable in terms of concentration, distribution and
availability. This experiment suggests that a culture on this soil wouldn’t mobilize the
pollution.
Domaines
Sciences du Vivant [q-bio]
Origine : Accord explicite pour ce dépôt
Origine : Accord explicite pour ce dépôt