Effects of Biochars Derived from Sewage Sludge and Olive Tree Prunings on Cu Fractionation and Mobility in Vineyard Soils over Time

Copper-contained products that are widely employed yearly in viticulture for vine disease management, lead to Cu accumulation topsoil creating an increased risk land workers and leaching and/or uptake of by plants, especially acidic soils where mobility is higher. In this study, the impact two biochar types on distribution redistribution fractions was evaluated four vineyard relation incubation time. The biochars were derived from sewage sludge (SG) olive tree prunings (OL). Soils (control) biochar-amended with application rate 20 % (w/w) spiked CuCl2 (160 mg kg−1) incubated laboratory at ambient temperature 22 ± 5 °C. After 1, 3, 7, 15, 36, 90 days incubation, modified BCR sequential extraction procedure used determine soil chemical phases examine potential between these both amended biochars. Results show amendment affects different fractions. SG treatment, 1st up 36th day, exchangeable reducible decreased, while oxidizable increased, control soils. At 90th a observed, mainly residual fraction. OL during first 36 slightly decreased. day higher percentage extracted fraction, but present remarkable quantities three studies studied highly restricted availability added promoting Cu-stable forms thus reducing environmental did not substantially reduce available fraction over experimental period. Fourier transformation infrared analysis (FTIR) provided convincing explanations behavior types.