溶磷真菌及其组合对复垦土壤磷解析和转化的影响

为了探索溶磷真菌在复垦土壤上对磷的作用效果,通过盆栽油菜试验,研究了黑曲霉(Aspergillus niger)、青霉(Penicillium)、被孢霉(Mortierella)及其组合对复垦土壤磷解析特性及无机磷转化的影响。结果表明,施用溶磷真菌可以增加复垦土壤有效磷、磷酸酶的量。溶磷真菌及其组合处理复垦土壤有效磷、磷酸酶量分别比基质处理(M)增加了58.6%~158.9%和3.7%~87.8%。施用有机肥可以明显改善复垦土壤的解析特性;被孢霉、被孢霉+青霉、黑曲霉+青霉、被孢霉+黑曲霉+青霉处理的土壤最大吸磷量都显著小于基质处理(M);不同处理复垦土壤吸附常数范围在0.036~0.069之间,溶磷真菌处理土壤磷吸附常数与基质处理(M)差异不显著;各处理复垦土壤磷平均解吸率在21.14%~34.57%之间,其中黑曲霉+青霉处理(Z2+Z3)复垦土壤平均解吸率最大,为34.57%。溶磷真菌对复垦土壤O-P、Fe-P、Al-P影响较小,对复垦土壤无机磷转化影响最大的是Ca2-P和Ca10-P,溶磷真菌可以抑制土壤中外来磷源向Ca10-P的转化,增加Ca2-P的量,溶磷真菌Z2+Z3处理Ca2-P的量最高,为28.73 mg/kg。综上,施用溶磷真菌可以增加复垦土壤有效磷量和提高磷素的有效性,有利于复垦土壤的熟化;黑曲霉+青霉处理(Z2+Z3)对复垦土壤解析特性及无机磷转化影响最大,为试验最佳处理。

Effect of Soluble Phosphorus Fungi and Their Combinations on Adsorption-desorption of Phosphorus and Its Transformation in a Reclaimed Soil

We studied the effect of phosphorus-dissolving fungi on phosphorus in reclaimed soil using pot experi-ments grown with rape. Three fungi, Aspergillus niger (Z1), Penicillium (Z2), Mortierella (Z3) and their combina-tions were examined. During the experiment, we measured the adsorption-desorption and the transformation of the phosphorus. The results showed that the soluble phosphorus fungi could increase the effective phosphorus and phosphatase contents in the reclaimed soils. The treatments with soluble phosphorus fungi and their combination increased the contents of available p and phosphatase by 58.6％～158.9％ and 3.7％～87.8％, respectively, com-pared with those without soluble phosphorus fungi treatment. The maximum adsorption capacity of p under com-binations of Z1, Z1+Z3, Z2+Z3, Z1+Z2+Z3 were significantly smaller than that without soluble phosphorus fun-gi treatment. The adsorption coefficient varied from 0.036～0.069, and the P adsorption between treatments with soluble phosphorus fungi and the non-treatment was insignificant. The average desorption rate in all treatments ranged from 21.14％to 34.57％, and the highest desorption rate was in Z2+Z3, which was 34.57％. The soluble phosphorus fungi had no effect on transformation of O-P, Fe-P and Al-P, while Ca2-P and Ca10-P had substantial impact on transformation of inorganic phosphorus. The soluble phosphorus fungi could inhibit transformation of phosphorus to Ca10-P and increased the content of Ca2-P. Z2+Z3 gave the highest Ca2-P content, being 28.73 mg/kg. In summary, applying phosphorus-dissolving fungi could increase the available phosphorus and improve phos-phorus availability in reclaimed soil, facilitating recovery of reclaimed soil. Our experiment revealed that the Z2+Z3 combination is most efficient in improving phosphorus desorption and transformation.