title: Sewage sludge application in a plantation: effects on trace metal transfer in soil-plant-snail continuum.
abstract: We studied the potential bioaccumulation of Cu, Zn, Pb and Cd by the snail Cantareus aspersus and evaluated the risk of leaching after application of sewage sludge to forest plantation ecosystems. Sewage sludge was applied to the soil surface at two loading rates (0, and 6 tons ha(-1) in dry matter) without incorporation into the soil so as to identify the sources of trace metal contamination in soil and plants and to evaluate effects on snail growth. The results indicated a snail mortality rate of less than 1% during the experiment, while their dry weight decreased significantly (<0.001) in all treatment modalities. Thus, snails showed no acute toxicity symptoms after soil amendment with sewage sludge over the exposure period considered. Additions of sewage sludge led to higher levels of trace metals in forest litter compared to control subplots, but similar trace metal concentrations were observed in sampling plants. Bioaccumulation study demonstrated that Zn had not accumulated in snails compared to Cu which accumulated only after 28 days of exposure to amended subplots. However, Pb and Cd contents in snails increased significantly after 14 and 28 days of exposure in both the control and amended subplots. At the last sampling date, in comparison to controls the Cd increase was higher in snails exposed to amended subplots. Thus, sludge spread therefore appears to be responsible for the observed bioaccumulation for Cu and Cd after 28days of exposure. Concerning Pb accumulation, the results from litter-soil-plant compartments suggest that soil is this metal's best transfer source.
authors.affiliation: Université de Franche-Comté, Laboratoire de Chrono-Environnement, UMR CNRS 6249, Besançon, France.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Bourioug
authors.affiliation: Université de Franche-Comté, Laboratoire de Chrono-Environnement, UMR CNRS 6249, Besançon, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Gimbert
authors.affiliation: Université de Franche-Comté, Laboratoire de Chrono-Environnement, UMR CNRS 6249, Besançon, France.
authors.forename: Laurence
authors.initials: L
authors.lastname: Alaoui-Sehmer
authors.affiliation: RITTMO Agroenvironnement, ZA Biopôle, 37 rue de Herrlisheim, CS 80023, F-68025 Colmar Cedex, France.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Benbrahim
authors.affiliation: Université de Franche-Comté, Laboratoire de Chrono-Environnement, UMR CNRS 6249, Besançon, France. Electronic address: lotfi.aleya@univ-fcomte.fr.
authors.forename: Lotfi
authors.initials: L
authors.lastname: Aleya
authors.affiliation: Université de Franche-Comté, Laboratoire de Chrono-Environnement, UMR CNRS 6249, Besançon, France.
authors.forename: Badr
authors.initials: B
authors.lastname: Alaoui-Sossé
mesh_terms: D000383:Agriculture / Q000379:methods*; D000818:Animals; D004784:Environmental Monitoring; D006372:Helix, Snails / Q000378:metabolism*; D008670:Metals / Q000032:analysis* / Q000378:metabolism; D010944:Plants / Q000737:chemistry / Q000378:metabolism; D012722:Sewage; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis* / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D008670:Metals; D012722:Sewage; D012987:Soil; D012989:Soil Pollutants
keywords: Bioaccumulation; Cantareus aspersus; Forest plantation; Microcosm; Sewage sludge; Trace metal