Phosphorus accumulation and inorganic phosphorus fractions in greenhouse soils

According to Jiang-Gu inorganic phosphorus fractions classification systems,the characteristic of phosphorus accumulation,inorganic phosphorus fractions and bio-availability how to change with vegetable cultivation years in greenhouse soil in Luoyang suburb were studied.The difference between greenhouse and white-corn rotation land were discussed too.The results indicated that while vegetable cultivation years were increased,the total phosphorus of soil was increased too.It was achieved 4.22 g/kg of total phosphorus in 15～17 years greenhouse.Available phosphorus concentration were increased too and it achieved the maximum in 11 years.The most amount phosphorus were accumulated in Ca2-P、Ca8-P、Al-P 、Fe-P in the first 5 years,and the dominat fraction were Ca2-P、Ca8-P.While vegetable cultivation years were increased,the amount of phosphorus accumulated in O-P、Ca10-P were increased.And Ca10-P was the dominant fraction.Others fractions' concentration were decreased while were increased.Vegetable cultivation years had no influence on propotion of calcium combined phosphorus and no calcium combined phosphorus.