The effects of exogenous La on the fertility parameters such as cation exchange capacity ( CEC), exchangeable basic cations, and exchangeable acidity in red soil and paddy soil were studied with soil column simulation...The effects of exogenous La on the fertility parameters such as cation exchange capacity ( CEC), exchangeable basic cations, and exchangeable acidity in red soil and paddy soil were studied with soil column simulation. The results show that with increasing amount of the added La, the proportion of exchangeable La in soils increases and there is more exchangeable La in red soil than in paddy soil. When the concentration of La is more than 600 mg(.)kg(-1) the proportion of exchangeable La almost remains constant. When the concentration of La is less than 1200 mg(.)kg(-1) there is no significant effect on CEC in red soil. But when the concentration of La is more than 1200 mg(.)kg(-1,) it has significant effect on CEC in paddy soil. The application of La resulted in increasing exchangeable aluminum, Ca and Mg in soil solution, and decreasing exchangeable Ca and Mg retained in soils. But when the concentration of La is less than 150 mg(.)kg(-1), it has no significant influence on CEC, exchangeable Ca and Mg, and exchangeable acidity in red soil and paddy soil.展开更多
文摘The effects of exogenous La on the fertility parameters such as cation exchange capacity ( CEC), exchangeable basic cations, and exchangeable acidity in red soil and paddy soil were studied with soil column simulation. The results show that with increasing amount of the added La, the proportion of exchangeable La in soils increases and there is more exchangeable La in red soil than in paddy soil. When the concentration of La is more than 600 mg(.)kg(-1) the proportion of exchangeable La almost remains constant. When the concentration of La is less than 1200 mg(.)kg(-1) there is no significant effect on CEC in red soil. But when the concentration of La is more than 1200 mg(.)kg(-1,) it has significant effect on CEC in paddy soil. The application of La resulted in increasing exchangeable aluminum, Ca and Mg in soil solution, and decreasing exchangeable Ca and Mg retained in soils. But when the concentration of La is less than 150 mg(.)kg(-1), it has no significant influence on CEC, exchangeable Ca and Mg, and exchangeable acidity in red soil and paddy soil.