硫酸铝改良剂对苏打盐碱土磷素吸附特性的影响

Effect of Aluminum Sulfate on Adsorption Properties of Phosphorus in Soda Salinealkali Soil

通过模拟盆栽改良试验和吸附试验,研究了施用硫酸铝改良剂后对土壤中磷的吸附特性的影响。结果表明:各处理土壤磷的等温吸附曲线与Freundlich、Langmuir和Temkin方程都比较吻合,但与Langmuir方程的吻合程度最好,其相关程度达极显著水平。根据Langmuir方程,将C/x/m对C作图,发现在施磷条件下,得到的是具有1个折点的直线,表明随着磷平衡浓度的不同,土壤对磷的吸附存在着2个不同能量水平的吸附点位。硫酸铝的用量越多,吸附磷量也越高。因此,应控制改良剂的用量,以0.3%为最好。

Effects of aluminum sulfate on adsorption properties of phosphorus were studied through indoor model experiments and adsorption experiments. The results showed that the adsorption isotherms were fitted well with Freundlich equation, Langmuir equation, and Temkin equation. But the single Langmuir equation was the best one. According to the single Langmuir equation, a plot of C/x/m against C gave a linear relationship that was formed by a broken-line plot under phosphate fertilizer application condition, indicating the existence of two populations of sites that have a differing affinity. Moreover, the adsorption amount of phosphorus would increase with the increase of aluminum sulfate amount, and NPA- 0.3 % was the optimal amount.