Then by methods of fractionation of inorganic and organic p in soils and multivariate statistical analysis , this paper discussed phosphorus fractions in soils with three fertility levels and in different soil layers . the affecting factors on fast - available p ( avail . p ) were also related 在此基礎(chǔ)上,用無(wú)機(jī)磷分級(jí)和有機(jī)磷分組方法、多元統(tǒng)計(jì)分析的方法,研究了石灰性土壤不同肥力與不同土層中磷素的各種形態(tài)含量差異以及影響速效磷的因素,結(jié)果如下: 1