Study On The Nutrient Transport And Transformation In Soil With Sewage Irrigation

Study on the mechanism of nutrient transport and transformation under sewage irrigation is very important for effective utilization of sewage effluent and pollution control. B ase on the study of lab experiment, the characteristics of nitrogen and phosphorus transport and transformation in soil was studied under sprinkler irrigation and flood irrigation. The soil was selected from Yamalik mountain, in Urumqi, Xinjiang, and the adsorption patterns of NH₄⁺ and H₂PO₄ can be described by Linear, Langmuir,Freundlich and Temkin isothermal adsorption model.The results showed that NH₄⁺—N concentration has increased after sewage irrigation. After 7 days, denitrification was dominant position, NH₄⁺—N concentration has decreased and NO₃ —N concentration was increased. After 30 days, NH₄⁺—N concentration was same in the soil under the two types of irrigation; because of nitrification, NO₃^- — N concentration became higher in the soil of sewage irrigation than rinsing irrigation. Under flood irrigation, the pore water velocity was high due to the great intensity of water supply which caused NH₄⁺—N to continue transporting. So NH₄⁺—N was not easy to adsorb by soil colloid while NO₃^- —N transported quickly. NH₄⁺—N and NO₃^-—N transportation is different because of different irrigation methods. Under sprinkler irrigation, the intensity of water supply was controlled and the pore water velocity was small, so NH₄⁺—N was adsorbed by soil colloid timely and nutrients transported slowly. Therefore, sprinkler irrigation was favored for plant to absorb and use...