title: Copper and zinc accumulation and fractionation in a clayey Hapludox soil subject to long-term pig slurry application.
abstract: Pig slurry (PS) recycling as fertilizer is commonly practiced as an option for minimizing livestock waste. Successive PS applications on the soil can lead to crop toxicity and environmental risk. Despite extensive investigation of macronutrient behavior, the fate of trace metals remains uncertain and only a few long-term field studies have been reported to date. This study was designed to assess the impact of 11-year continuous PS spreading on Cu and Zn accumulation and fractionation in a Brazilian clayey Hapludox soil. Three different PS application rates--50, 100 and 200m3 ha(-1)year(-1)--were monitored at six soil depths in comparison to a non-amended control soil. The modified Geological Survey of Canada sequential extraction protocol was applied. A statistically significant increase in Cu and Zn total concentration (assessed by the sum of fractions) was noted only within the 0-5 cm soil layer for the 50 and 100 m3 ha(-1) year(-1) (PS50 and PS100) treatments, and up to 10-15 cm for the 200 m3 ha(-1)year(-1) (PS200) treatment. The mass balance, determined for the 22 PS amendments over the period, confirmed the overall exogenous Cu and Zn accumulation within the surface layers. More than 70% of the natural heavy metal content was originally in the residual fraction. However, this was the only fraction not influenced by the PS amendments. After PS input, the exogenous Cu was mainly detected in the fraction bound to organic matter (66.4%) within the PS200 0-5 cm soil layer. Exogenous Zn was mainly distributed between the adsorbed fraction (36.7%) and the organic matter fraction (32.0%) within the PS200 0-5 cm layer.
authors.affiliation: Department of Hydraulics and Sanitation, Federal University of Parana, 81531-980 Curitiba, PR, Brazil. Electronic address: formentini@gmail.com.
authors.forename: Thiago Augusto
authors.initials: TA
authors.lastname: Formentini
authors.affiliation: CAPES Foundation, Ministry of Education of Brazil, 70040-020 Brasilia, DF, Brazil.
authors.forename: Fábio Joel Kochem
authors.initials: FJK
authors.lastname: Mallmann
authors.affiliation: Environmental Engineering Program, Regional University of Blumenau, 89030-000 Blumenau, SC, Brazil.
authors.forename: Adilson
authors.initials: A
authors.lastname: Pinheiro
authors.affiliation: Department of Hydraulics and Sanitation, Federal University of Parana, 81531-980 Curitiba, PR, Brazil.
authors.forename: Cristovão Vicente Scapulatempo
authors.initials: CVS
authors.lastname: Fernandes
authors.affiliation: Department of Soils, Federal University of Santa Maria, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Marcos Antonio
authors.initials: MA
authors.lastname: Bender
authors.affiliation: EPAGRI, P.O. Box 116, 89620-000 Campos Novos, SC, Brazil.
authors.forename: Milton
authors.initials: M
authors.lastname: da Veiga
authors.affiliation: Department of Soils, Federal University of Santa Maria, 97105-900 Santa Maria, RS, Brazil.
authors.forename: Danilo Rheinheimer
authors.initials: DR
authors.lastname: Dos Santos
authors.affiliation: CIRAD, UPR Recyclage et risque, F-34398 Montpellier, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Doelsch
mesh_terms: D000383:Agriculture / Q000379:methods*; D000818:Animals; D003300:Copper / Q000032:analysis*; D004784:Environmental Monitoring; D012987:Soil; D012989:Soil Pollutants / Q000032:analysis*; D034421:Sus scrofa; D014865:Waste Disposal, Fluid / Q000379:methods*; D015032:Zinc / Q000032:analysis*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D003300:Copper; D015032:Zinc
keywords: Organic waste; Sequential extraction; Soil amendment; Trace elements