Comparison Function Kiwi Skin on Mobility of Heavy Metals (Copper and Zink) in Contaminated Sandy soil and Function silk worm cocoon on Mobility of Heavy Metals (Copper and Zink) in Contaminated Clay soil

Contamination of soils with heavy metals is caused either in a natural manner or by human activities such as industrial and mining activities. The soil contaminations with heavy metals are regarded as one of the environmental issues. Heavy metals in soil are distributied among several fraction which include water soluble fraction, exchangeable fraction, organic associated fraction, carbonate associated fraction, bound and accluded in oxides and residual fraction. This study aimed to study the effect of incubation time of natural absorbents (kiwi skin and silk worm cocoon) on the mobility decrease of some heavy metals such as copper (Cu) and zinc (Zn), in contaminated sandy and clay soils. The soils were synthetically contaminated in the laboratory with multi-componet solutions. The experiments were performed in two replicates and four treatments ( sandy soil without adding kiwi skin and clay soil without adding silk worm cocoon (controls) and sandy soil contain kiwi skin and clay soil contain silk worm cocoon). The samples were kept at fixed temperature of 28oC for 3 hours, 1, 3, 7, 14, 21 and 28 days. Then, concentration of Cu and Zn were studied in soils components using sequential extraction. after 28 days ( sandy soil with kiwi skin), (Cu) distribution in organic phase was higher than other phase and distribution of (Zn) was high in manganese and iron Phase. after 28 days (clay soil with silk worm cocoon), (Cu) distribution in manganese and iron Phase was higher than other phase and distribution of (Zn) was high in manganese and iron Phase.