Geochemical Behavior of Zinc, Potassium and Sodium in Soils Affected by Acid Rains Related to Sar Cheshmeh Copper Smelter, Rafsanjan

Occurrence of acid rains in the region adjacent to Sar Cheshmeh Copper Smelter, 155 km southwest of Kerman, was established by the measurement of pH of precipitations during 2005 and 2006. This paper deals with the geochemical behavior of Na, K and Zn in the entisols and inceptisols of Sar Cheshmeh region which was subjected to acid rains. Laboratory experiments were performed on 12 undisturbed soil core samples (50 cm long, 6 cm in diameter) with acid solutions of pH=3.1, pH=4.1 and pH=5.6. The sprinkling lasted 31 days, simulating a rainfall of 370 mm and the drainages were analyzed. Soil properties and forms of Na, K and Zn in 0-15cm, 15-50cm and 30-50cm depths determined before and after the simulation. Results show that some elements can be mobilized and leached out of the soils of the study area by the action of acid rain. Acid rain causes a decrease in the exchangeable form of sodium and potassium while soluble form of these elements increases. Furthermore, acid rain causes an increase in the available and soluble form of Zn.