根际试验研究表明，水分、有机质、土壤酸度是影响白浆土磷素生物有效性的重要因子．调节土壤水分含量，能增强土壤中铁、铝磷酸盐的溶解，加速磷酸根离子从根际土壤向非根际土壤扩散．增加土壤有机质含量，降低了土壤对Ｐ 素的吸附自由能（ Ｋ 值） ，提高土壤中的速效磷含量．适量施用石灰，调节白浆土酸度，由于化学溶解作用的影响，促进了土壤中铁、铝磷酸盐的溶解，增强了土壤中磷素的生物有效性 The rhizosphere experiment shows that the moisture, organic matter and soil acidity are important factors affecting the bioavailability of phosphorus in alluvial soil. Regulation of soil moisture content, can enhance the dissolution of iron and aluminum phosphate in soil, accelerate the diffusion of phosphate ions from rhizosphere soil to non-rhizosphere soil. Increase the content of soil organic matter, reduce the free energy of soil adsorption of P (K value), and increase the content of available P in the soil. Appropriate amount of lime, adjust the white soil acidity, due to the impact of chemical dissolution, promoted the dissolution of iron and aluminum phosphate in soil, enhanced the bioavailability of phosphorus in soil