| Abstract This research has studied the status and the availability of phosphorus accumulated in vegetable soils of Hebei province by investigation and simulated test. The result showed: Contrast to crop soil, total phosphorus and Olsen-P contents of 0-20cm, 20-40cm, 40-60cm, 60-80cm layers of vegetable soil increased by 2.3, 1.4, 0.4, 0.3 times and 11.4, 11.5, 5.4, 2.5 times, but the percentages of inorganic phosphorus in vegetable soil were almost the same as those in crop soil. Ca2-P increased by 6.5, 9.2, 4.2, 2.7 times, Ca8-P of vegetable soil increased by 10.7, 13.5, 1.7, 1.4 tiems. Al-P of vegetable soil increased by 4.5, 2.4, 1.0, 0.5 times. Fe-P of vegetable soil increased by 2.0, 2.4, 0.7, 0.3 times respectively, and there was no significant changes on 0-P and Ca10-P. Inorganic phosphorus fractions of vegetable soil sequence were: Ca3-P> Ca2-P>Al-P>Fe-P>O-P and ca10-P. There were significant differeces among different areas on the contents and percentages of phosphorus. The sequence of Olsen-P among areas were Shijiazhang> Langfang>Baoding>Tangshan>Handan>Qinhuangdao. The sequence of total phoshorus among areas were Shijiazhang> Langfang>Baoding>Tangshan> Handan> Qinhuangdao. On the spatial distribution, the accumulations of phosphorus mainly occurred in 0-20cm and 20-40cm layers. The percentages of Olsen-P of 20-40cm, 40-60cm, 60-80cm layers of vegetable soil to 0-20cm layer were 37.5%, 12.0%, 6.8%, and the percentages of crop soil were 38.6%, 23.9%, 22.6%. The perecentages of total phosphorus of 20-40cm, 40-60cm, 60-80cm layers of vegetable soil to 0-20cm layer were 53.2%, 26.9%, 21.2%, and the percentages of crop soil were 72.9%, 64.3%,52.9%. The percentages of Ca2-P of 20-40cm, 40-60cm, 60-80cm layers to 0-20cm layer of vegetable soil were 27.0%, 17.6%, 13.1%, the percentages of crop soil were 33.3%, 12.2%, 6.5%. The percentages of Ca3-P of 20-40cm, 40-60cm, 60-80cm layers to 0-20cm layer of vegetable soil were 41.9%, 5.7%, 2.6%, the percentages of crop soil were 33.8%, 24.8%, 12.7%. The percentages of Al-P of 43 20-40cm, 40-60cm, 60-80cm layers to 0-20cm layer of vegetable soil were 33.6%, 13.0%, 8.4%, the percentages of crop soil were 54.3%, 36.4%, 31.1%. The percentages of Fe-P of 20-40cm, 40-60cm, 60-80cm layers to 0-20cm layer of vegetable soil were 29.0%, 30.9%, 23.1%, the percentages of crop soil were 55.7%, 55.7%, 54.5%. Simulated test showed that the yield responses of rape to phosphate fertilizer in different fertility soil were very different. Applying phosphate fertilizer could increase the yield of rape in low fertility soil, the effect of phosphate fertilizer in moderate fertility soil was not found until the third batch, and there was no significant effect on the yield of rape in high fertility soil through three batches. During the simulated test, the contents of Olsen-P in different fertility soils all decreased because of the uptake of rape, and the positive interactions between phosphate fertilizer and manure was found. It also showed that Ca2-P Ca8-P Al-P and Fe-P were all the available sources of phosphorus which could be uptake by rape, but in different fertility soil, their contribution are different. In low fertility soil, Ca2-P, Ca8-P, Al-P and Fe-P are all the available sources to offer phosphorus, they account for 27.1%, 40.4%, 17.8%, 14.50/., in moderate fertility soil, the rates of CarP, Can-P, Al-P and Fe-P were 38.0%, 45.8~/.,...
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