Effect of enriched municipal waste compost with tire ash on sorghum Zn availability in a cadmium polluted soil (A case study: Arak municipal waste compost)

This research was performed to investigate the effect of tire ash enriched Arak municipal waste compost on the changes in Zn availability in a Cd polluted soil. Treatments were consisting of applying Arak municipal waste compost (0, 15 and 30 t ha-1) enriched with 0 and 200 kg ha-1 tire ash in a polluted soil (0, 5, 10 and 15 mg Cd kg-1 soil) and plant in this experiment was sorghum (Kimya CV.). Increasing the loading rate of Arak municipal waste compost from 0 to 15 t ha-1 in a Cd polluted soil (10 mg Cd soil-1) caused an increasing in DTPA extractable-Zn by 80 percentage. Similar to this result, after 60th from the experiment, the root and shoot Zn concentration were increased by 40 and 60 percentage, respectively. Applying tire waste had an effectiveness role on increasing Zn availability, as, applying 15 and 30 t ha-1 tire ash enriched Arak municipal waste compost in a Cd polluted soil (10 mg Cd kg soil-1) caused an increasing in DTPA extractable-Zn by 22 and 26 percentage, respectively. While the shoot Zn concentration was increased by 13 and 20 percentage, respectively. The result of this study showed that greatest shoot Zn concentration was to the treatment with applying 30 t ha-1 Arak municipal waste compost enriched with tire ash in a non-polluted soil. However, the type and physiological effect on the changes in Zn availability cannot be ignored.