Research on the Relationship between Particles and Levels of Phosphorus in the Alluvial Soils on the Yellow River Flood Plain in North China

The main type of soils on the Yellow River Flood Plain in North China is called Chaotu(alluvial soil) by Chinese. The levels of phosphorus of this alluvial soil are mainly affected by the texture, the contents of assorted particles. Based on the data of this soil published by provincial government,the relations of phosphorus with particles were analyzed by using methods of correlation. It is found out that the particles of sand and silt are the first two factors to contribute the content of total phosphorus, clay and less than 0.01mm particles to contribute the content to available phosphorus. Two mathematic models on the relationship between phosphorus (total phosphorus and available phosphorus) and particles of the soil are built by the method of stepwise regression. The result of predicting content of total phosphorus is better than that of available phosphorus.