method of fractionation造句

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
在此基础上，用无机磷分级和有机磷分组方法、多元统计分析的方法，研究了石灰性土壤不同肥力与不同土层中磷素的各种形态含量差异以及影响速效磷的因素，结果如下： 1
It's difficult to find method of fractionation in a sentence. 用method of fractionation造句挺难的