Phosphorus Adsorption Characteristics of Red Soil in Northern Suburban Area of the Dianchi Lake

The kinetics parameters and isothermal phosphorus adsorption of red soil in the northern suburban area of the Dianchi Lake were studied, and the differences in phosphorus adsorption parameters for different phosphorus concentration by soils with varied qualities were also compared. The results showed that the amount of phosphorus adsorbed by red soil increased as the vibration duration was prolonged. The isothermal phosphorus adsorption conformed to both Langmuir and Freundlish equations. Under the same temperature, the amount of phosphorus adsorbed increased along with the rising of phosphorus concentration, but the absorption rate dropped gradually. It was showed by Gibbs free energy calculation that the phosphorus adsorption process by red soil occurred spontaneously. Compared with other substrate material, the red soil has many advantages including higher adsorption capacity, lower in price and richer in local resources, so it was proposed that red soil should be given priority to be utilized to tackle with non-point phosphorus pollution in the northern suburban area of the Dianchi Lake.