اثرات شيرابه كمپوست زباله شهري بر قابليت جذب برخي عناصر كم مصرف در ذرت و كاهو

Effect of Municipal Waste Compost Leachate on Micronutrients Uptake by Maize and Lettuce in Sterile and Non-Sterile Conditions

In the process of conversion of solid waste refuses to compost, leachate is produced. Although municipal waste compost leachate is one of the problems of compost production in Iran, it may be considered as a source of water and nutrient. Municipal waste compost leachate contains micronutrients (Fe, Zn, Mn and Cu) that can be used by plants. Furthermore, microorganisms have important effects on nutrient cycle in soils. Therefore, a greenhouse experiment was conducted to study the effect of municipal waste compost leachate on micronutrients uptake by plant in sterile and non-sterile conditions, with three watering treatments (distilled water, non-sterile leachate and sterile leachate), three different treatments on soils (non-sterile soil, sterile soil + re-inoculation with non-sterile soil and sterile soil) and tow plants (lettuce, Lactuca sativa and maize, Zea mays) in a factorial complete randomized design with three replication. Results of this study showed that, plant uptake of Zn increased significantly under the leachate treatments. However, plant uptake of Fe, Mn and Cu were not affected by leachate treatments. In most cases, there was not significant difference between sterile and non-sterile leachate for micronutrients uptake by plant. Leachate application also increased DTPA extractable Fe but, DTPA extractable Zn Mn and Cu didnʹt show any significant increase under the leachate treatments. Although Zn uptake by plant increased under the leachate treatments, DTPA. In general, use of leachate in soil for lettuce and maize had positive effect on plant yield. Concentration of Fe, Zn, Mn and Cu in plants studied did not exceed standard permissible levels of the metals with the application of leachate as liquid organic fertilizer.