The effect of copper slag application along with organic compounds on DTPA extractable Iron and some properties of a calcareous soil

  Iron deficiency is one of the most common problems in the plant nutrition in arid and semi-arid regions soil, especially calcareous soil. Since iron oxides account for about 53. 8% of the slag, it can be used as a fertilizer. The use of copper slag of Sarcheshmeh Copper Complex sub-products was evaluated with organic compounds as the source of iron supply in calcareous soil. The purpose of this study was to study the effect of copper slag and organic compounds on the amount of extractable iron by DTPA and some characteristics of calcareous soil. In order to investigate the effect of slag on soil absorbable iron, an incubation test was performed for 3 months as a factorial experiment in a completely randomized design with three replications. The experimental factors consisted of 5 levels of organic matter (pistachio shell, cow manure 2 and 4% w / w and control sample) and 10 iron levels (copper slag, copper slag with sulfur, copper slag with sulfur and Thiobacillus, acid slag (each at two levels), Chelate Sequestrene and control sample). 10, 30, 60 and 90 days after incubation, changes in parameters such as pH, EC and iron content were measured by DTPA-TEA extractor. The results showed that by applying the organic compounds' treatments during the incubation time reduced the iron extraction capability. The results showed that during the three-month incubation period, slag treatments increased soil EC. The highest amount of EC increase in slag treatment is 4 times the recommended value of the soil test based on the absorbable iron content of this compound with sulfur and Thiobacillus S4S°T at 2. 21 dS / m at the end of the incubation period. In the soil sample studied, proportional to the amount of slag, the amount of iron extracted by DTPA increased. However, during the incubation period, the iron extraction capability was reduced; however, the amount of iron increased significantly after 90 days from the beginning of incubation in S4S°T and S4S°، S4 treatments compared with the control. The interaction effect of slag treatments and organic compounds showed that the highest amount of EC and the lowest pH were related to 4% cow manure application with slag with sulfur and Thiobacillus. Meanwhile, the amount of absorbable iron in the soil from 1. 43 mg / kg in the control treatment of CS° reached 8. 17 mg / kg in the treatment of 4% pistachio shell as 4 times of the recommended value of the soil test with sulfur and Thiobacillus (P4S4S°T). Organic compounds during the incubation period led to a reduction in iron compared to the control sample. Slag of copper smelting has nutrient micro-elements, including iron, so that at high levels of slag consumption, the amount of iron increased, as well as the use of slag with sulfur, Thiobacillus and pistachio shell had the most amount of absorbable iron As a result, slag has the potential to be used as an iron source for plants