Copper and zinc accumulation and fractionation in a clayey Hapludox soil subject to long-term pig slurry application.

摘要: Pig slurry (PS) recycling as fertilizer is commonly practiced 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, fate trace metals remains uncertain only a few long-term field studies have been reported date. This study was designed assess impact 11-year continuous spreading Cu Zn accumulation fractionation in Brazilian clayey Hapludox soil. Three different application rates -50, 100 200 m(3) ha(-1) year(-1) - were monitored at six depths comparison non-amended control The modified Geological Survey Canada sequential extraction protocol applied. A statistically significant increase total concentration (assessed by sum fractions) noted within 0-5 cm layer 50 (PS50 PS100) treatments, up 10-15 (PS200) treatment. mass balance, determined 22 amendments over period, confirmed overall exogenous surface layers. More than 70% natural heavy metal content originally residual fraction. However, this fraction not influenced amendments. After input, mainly detected bound organic matter (66.4%) PS200 layer. Exogenous distributed between adsorbed (36.7%) (32.0%) (C) 2015 Elsevier B.V. All rights reserved.