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根据北京市蔬菜地的分布状况，分别在近郊和远郊选取有代表性的蔬菜保护地，取０～１００ｃｍ深不同土层土样，研究北京郊区蔬菜保护地土壤磷空间及形态分布特征。结果表明，种菜时间越长，土壤中的全磷和有机磷含量也越多。近郊蔬菜保护地６个采样点０～２０ｃｍ土层土壤有效磷（ＯｌｓｅｎＰ）含量平均值为２１１ｍｇ·ｋｇ－１，远郊７个采样点平均值为９５ｍｇ·ｋｇ－１。均远远高于土壤磷大量淋失时的土壤表层有效磷含量。蔬菜保护地土壤全磷、有机质和有效磷均呈表层含量较高，２０ｃｍ以下含量骤减，土层越深含量越低的规律。土壤有机磷则随土层加深缓慢降低。随土层深度增加，有效磷占全磷的比例逐渐下降而有机磷占全磷的比例则逐渐增加；土壤全磷、有机磷、有机质和有效磷四者之间均呈极显著正相关。
According to the distribution of vegetable land in Beijing, representative protected areas of vegetables were selected in the outskirts and outskirts respectively. Soil samples from different depths of 0 ~ 100 cm were taken to study the spatial distribution and distribution characteristics of soil P in vegetable reserves in Beijing suburbs. The results showed that the longer the planting time, the more total phosphorus and organic phosphorus in the soil. The average content of soil available phosphorus (P <0.05) in the 0-20 cm soil layer of 6 sampling sites in suburb vegetable conservancy was 211 mg · kg-1, and the average value of 7 sampling points in the outer suburbs was 95 mg · kg-1. Are much higher than the soil available phosphorus content when the soil leaching a lot of leaching. The total phosphorus, organic matter and available phosphorus in the soils protected by vegetable showed the regularity of higher surface content, less content under 20cm, and lower content of deeper soil layers. Soil organic phosphorus decreased slowly with the soil depth. With the increase of soil depth, the ratio of available phosphorus to total phosphorus decreased gradually and the proportion of organic phosphorus to total phosphorus increased gradually. There was a significant positive correlation between soil total phosphorus, organic phosphorus, organic matter and available phosphorus.