Abstract:

In order to explore the cause of formation and mechanism of high yield, and provide the theory basis fo artificial directional cultivating and efficient use of P. The representative of black soil in corn belt of the Songliao Plain was used as the soil for experiment, on the basis of field investigation and collection of different profile samples, studied phosphorus content of composition and absorption property in the high yield black soil. The results showed that, the contents of total phosphorus and available P of high yield were higher than its control group soil which was in the same depth of soil. With the increase of soil depth the contents of total phosphorus and available P reduced, total phosphorus and available P of high yield both had obvious accumulation, and the content of topsoil was 0.505 g/kg and 32.0 mg/kg, they were 1.2 times and 1.05 times than control group soil respectively. The different forms of inorganic phosphorus of high yield composing was Ca10-P (79.7%-16.0%) > Fe-P (27.1%-8.1%) > Al-P (27.2%-4.6%) > Ca8-P (21.0%-4.3%) > Ca2-P (10.6%-0.4%) > O-P (4.6%-1.4%), the control group soil composing was Ca10-P (77.6%-27.2%) > Fe-P (21.2%-9.4%) > Al-P (26.9%-2.2%) > Ca8-P (21.0%-4.0%) > Ca2-P (8.6%-1.2%) > O-P (7.8%-1.4%). The available phosphorus of the black soil with draw by Olsen-p method mainly was Ca2-P, Ca8-P, Al-P, Fe-P, but the effectiveness of Ca10-P and O-P was very low but they were potential phosphorus of plants.