Fate of metal-associated POM in a soil under arable land use contaminated by metallurgical fallout in northern France.
Organic matter is a major metal-retaining constituent in soils. Among the diversity of organic components in soils, particulate organic matter (POM) accumulates large amounts of metals, but the fate of such metal-associated POM is unknown. We studied different POM size fractions and their corresponding mineral size-fractions isolated from the surface horizon of a soil affected by metallurgical fallout. Analyses of total and EDTA extractible metal contents performed on all size fractions demonstrated that with decreasing POM size, larger metal concentrations were observed but they were less extractable. Micromorphological study revealed the occurrence of opaque parts in decaying POM fragments and their individualization as fine, irregularly shaped opaque fragments in the soil matrix. This work suggested a mutual sequestration of metal pollutants and organic carbon as micro-meter sized, metal-enriched organic particles derived from POM, representing an original pathway for natural attenuation of risk related to metal contaminated soils.
Labanowski
Jérôme
J
INRA, UR 251 Unité PESSAC, RD 10, F-78026 Versailles Cedex, France.
Sebastia
Julien
J
Foy
Eddy
E
Jongmans
Toine
T
Lamy
Isabelle
I
van Oort
Folkert
F
D000383:Agriculture; D001673:Biodegradation, Environmental; D004463:Ecology / Q000379:methods; D004492:Edetic Acid; D004784:Environmental Monitoring / Q000379:methods; D004787:Environmental Pollution; D005602:France; D006812:Humic Substances; D008670:Metals / Q000032:analysis*; D008853:Microscopy; D052638:Particulate Matter; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D052616:Solid Phase Extraction; D013997:Time Factors
D006812:Humic Substances; D008670:Metals; D052638:Particulate Matter; D012987:Soil; D012989:Soil Pollutants; D004492:Edetic Acid