The Studies On Transformation,Influence Factors And Availability Of Phosphorus Fertilizer In Vegetable Soil

This research studied the transformation of phosphorus fertilizer, influence factors and availability of phosphorus accumulated. The results showed: The yield of rape in applying phosphorus and manure fertilizer treatment was respectively higher 22.7%, 25.4% than that in check treatment. The effect of phosphate and manure fertilizer was not found in moderate and high P lever soil. After planting seven batches, phosphorus fertilizer had manifest after-effect in low and moderate P iever soil, but the after-effect of phosphorus fertilizer was not found in high P lever soil.The yield of rape in moderate and high P lever soil more than that in low P lever soil.Olsen-P contents in vegetable soil gradually decreased with the batches increasing. After seven batches. Olsen-P contents of check treatment respectively decreased 30.7mg/kg. 99.0mg/kg, 143.3mg/kg in low, moderate and high fertility soils. Olsen-P contents of applying phosphorus fertilizer treatment was more 9.2%. 27.0%. 20.2% than that of check treatment in low, moderate and high P lever soils.The contribution rate of inorganic phosphorus: In low fertility soil, the contribution rates of Ca:-P, Ca8-P, AI-P and Fe-P were 18.9%, 33.3%, 20.2%, 23.7%; in moderate fertility soil, the rates of Ca:-P, Ca8-P, Al-P and Fe-P were 38.8%, 29.8%. 15.2%. 13.1%; in high fertility soil, the rates of Ca:-P, Ca8-P, AI-P and Fe-P were 24.8%, 37.2%. 18.6%, 17.4%. In different fertility soil, the transformation of phosphorus fertilizer were different. In low fertility soil, the accumulation use rate of phosphorus fertilizer was 41.3%, the contents of phosphorus fertilizer converting into Ca,-P, Cas-P. Al-P and Fe-P accounted for applying total phosphorus fertilizer 7.8%, 30.8%, 16.1%, 4.8%; in moderate fertility soil, the accumulation use rate of phosphorus fertilizer was 19.4%. and the rates of transformation were 22.0%, 43.2%, 15.2%. 3.0%; in high fertility soil, the accumulation use rate of phosphorus fertilizer39?2002was 21.2%. the rates of transformation were 14.1%, 55.0%, 11.6%, 2.1%. The transformation of O-P and CalO-P was not distinct.Under the condition of no planting, the rate of fixed phosphorus gradually increased with the cultivation time. The fixation rate of phosphorus fertilizer in high P lever soil was distinctly lower than that in low P lever soil. The rate of fixed phosphorus increased in manure + P fertilizer treatment compared with P fertilizer treat before 40 days in cultivation, but decreased after 40 days.The effect of phosphorus fertilizer on yield of rape: The results showed that applying phosphorus fertilizer increased the yield of rape than no applying phosphorus fertilizer. Applying 50mg/kg phosphorus increased the yield of rape by 12.4% than Applying 25mg/kg phosphorus. The rape yields of applying 50mg/kg, 75mg/kg, lOOmg/kg, 150mg/kg, 200mg/kg treatments had no distinct difference. Applying 300mg/kg phosphorus, the yield of rape distinctly decreased. The Olsen-P contents in soil and the total phosphorus contents of rape all increased with the applied P fertilizer increasing, but the total Zn contents of rape decreased.