ويژگي هاي جذب سطحي روي در خاك هاي كشت صنعت نيشكر در شمال خوزستان (هفت تپه و شوشتر)

Characterization of Zinc Adsorption in Some Sugar-cane Agro-Industry Soils in North- Khouzestan (Haft- Tapeh and Shoshtar)

Absorption capability of micronutrient elements such as Zn is important for optimum plant growth. It has been reported that zinc deficiency is the most common deficiency cationic micronutrient elements in calcareous and alkaline soils. Most of the sugarcane cultivated soils in Khouzestan- Iran have a high level of CaCO3 content (> 40%) with a pH greater than 7.0. Hence, availability of zinc and maintaining mechanisms of this element in soil surfaces are important. One of the important mechanisms that had not been investigated in these lands is adsorption phenomena of the elements. Eight surface soil samples from the sugarcane cultivated soils (0- 30 cm) from two sugarcane agro industry were used to study the zinc adsorption characteristics in these soils. The absorption data were fitted to Freundlich and Langmuir adsorption isotherms and respective coefficients were calculated. The absorption data presented a highly significant fit to Freundlich and also to the two-surface Langmuir absorption. The results clearly showed that the Freundlich equation can explain the adsorption Zn in sugarcane cultivated soils much better than the Langmuir equation. The regression between the coefficients of equations absorption and some soil physical and chemical properties was established. The coefficients of both equations showed significant positive correlation with clay percentage and caution exchange capacity, and significant negative correlation with carbonate calcium percentage in sugar cane cultivated soils.