| Autor: |
Mattiello EM; Department of Soil Science, Universidade Federal de Viçosa , Viçosa, Minas Gerais 36570-900, Brazil., da Silva RC; School of Agriculture, Food and Wine, The University of Adelaide , PMB 1, Waite Campus, Glen Osmond, SA 5064, Australia., Degryse F; School of Agriculture, Food and Wine, The University of Adelaide , PMB 1, Waite Campus, Glen Osmond, SA 5064, Australia., Baird R; School of Agriculture, Food and Wine, The University of Adelaide , PMB 1, Waite Campus, Glen Osmond, SA 5064, Australia., Gupta VV; CSIRO Agriculture and Food , PMB 2, Glen Osmond, SA 5064, Australia., McLaughlin MJ; School of Agriculture, Food and Wine, The University of Adelaide , PMB 1, Waite Campus, Glen Osmond, SA 5064, Australia.; CSIRO Land and Water , PMB 2, Glen Osmond, SA 5064, Australia. |
| Abstrakt: |
Acidification by oxidation of elemental sulfur (ES) can solubilize ZnO, providing slow release of both sulfur (S) and zinc (Zn) in soil. For this study, a new granular fertilizer with ES and ZnO was produced and evaluated. The effect of incorporating microorganisms or a carbon source in the granule was also evaluated. Four granulated ES-Zn fertilizers with and without S-oxidizing microorganisms, a commercial ES pastille, ZnSO 4 , and ZnO were applied to the center of Petri dishes containing two contrasting pH soils. Soil pH, CaCl 2 -extractable S and Zn, and remaining ES were evaluated at 30 and 60 days in two soil sections (0-5 and 5-9 mm from the fertilizer application site). A visualization test was performed to evaluate Zn diffusion over time. A significant pH decrease was observed in the acidic soil for all ES-Zn fertilizer treatments and in the alkaline soil for the Acidithiobacillus thiooxidans-inoculated treatment only. In agreement with Zn visualization tests, extractable-Zn concentrations were higher from the point of application in the acidic (62.9 mg dm -3 ) compared to the alkaline soil (5.5 mg dm -3 ). Elemental S oxidation was greater in the acidic soil (20.9%) than slightly alkaline soil (12%). The ES-Zn granular fertilizers increased S and Zn concentrations in soil and can provide a strategically slow release of nutrients to the soil. |
