Study On Forest Soil Phosphate In Badaling Mountain Of Beijing

By the method of principal component and correlation analysis, the succession pattern of phosphorus and phosphates activity in soil profile and rhizosphere soil in Beijing North Mountain was revealed. The relationship between phosphates, phosphorus forms, and soil basic nature was explained. The principal index and control measure was proposed.The results showed: soil alkalihydrolyzable nitrogen and available K of plantations was at low level, soil total phosphorus and available phosphorus was at lowest level in general, pH is weak acid or neutral, soil nutrition had surface accumulate. The total soil organic phosphorus content were 25.61 mg·kg^-1～96.80mg·kg^-1, amounted to 5.61%～26.04% of the total phosphorus. The main components of soil organic phosphorus were moderately labile and labile organic phosphorus, amounted to 5.61%～26.04% of the total organic phosphorus, the moderately labile and labile organic phosphorus were the main sources of soil available phosphorus. The total soil inorganic phosphorus content were 51.35mg·kg^-1～492.90mg·kg^-1, amounted to 32.26%～79.31% of the total phosphorus, The main components of soil inorganic phosphorus were Ca-P, amounted to 56.68%～84.96% of the total inorganic. The acid phosphates activity content were 2.22 mg·g^-1·h^-113.64 mg·g^-1·h^-1, alkaline phosphates activity content were 0.29¹0.34 mg·g^-1·h^-1, acid phosphates activity were higher than alkaline phosphates. Soil phosphorus had rhizosphere effect, rate between 1.24¹11.There was a closely positive relation between contents of soil nutrition, organic phosphorus, inorganic phosphorus. By the method of PCA, five synthesized factors were selected as targets on evaluating soil fertility .The first factors was soil organic phosphorus, second was soil inorganic, , third were synthetically soil organic and phosphates, fourth was phosphates kinetic characteristics, fifth were synthetically labile organic phosphorus and Al-P. The soil available phosphorus, Al-P, organic matter, acid phosphates, moderately labilepool, Ca10-P , Ca8-P, directly affected the level of phosphorus supply.