نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی سابق کارشناسی ارشد خاکشناسی دانشگاه بوعلی سینا
2 دانشیار گروه خاکشناسی دانشگاه بوعلی سینا
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
The distribution of cadmium (Cd), zinc (Zn) and lead (Pb) in two clay and sandy soils were examined using soil column leaching experiments. Glass tubes, 4.8 cm diameter and 40 cm long were packed to 30 cm depth. The columns were irrigated with spiked sewage containing 8.5 mg l-1 Zn and Cd and 170 mg l-1 Pb for 30 days. Similar column was packed with sandy soil and irrigated with sewage alone. At the end of leaching experiments, soil columns were cut into three layers each being 1 cm depths. The fractionation of above elements was investigated using sequestration extraction method. The elements were fractionated into different forms: exchangeable (F1), bound to carbonate (F2), bound to Mn oxides (F3), bound to Fe oxides (F4), bound to organic matter (F5), and residual (F6). Application of spiked sewage significantly increased concentration of Cd, Zn and Pb in surface layer (0-1 cm). Results showed that in two soils Cd was mainly in F2 fraction. In two soils Zn was mainly in F6 fraction. Lead in sandy soil was mainly in F2 fraction and in clay soil was in F4 fraction. The fractionation of these elements indicated that they are mainly in nonlabile forms. Thus, in short period, the possibility of contamination of groundwater with these elements is low
کلیدواژهها [English]