Determination standard of total phosphorus in soil
Soil total phosphorus is the total phosphorus reserves, including organic phosphorus and inorganic phosphorus. Most of the phosphorus in the soil exists in the later action state, so the total phosphorus content in the soil can not be used as the index of phosphorus supply in the soil. A high total phosphorus content does not mean sufficient phosphorus supply, while a low total phosphorus content may mean insufficient phosphorus supply. Therefore, understanding the total reserves of soil phosphorus is only of certain reference value to production practice.
Although there is no linear correlation between available phosphorus content and total phosphorus content in soil, when the total phosphorus content in soil is lower than 0.03%, the soil often lacks available phosphorus. Soil available phosphorus is an index of soil phosphorus supply level, and soil phosphorus content reflects the storage and supply capacity of soil phosphorus to some extent.
References:
Baidu encyclopedia-available phosphorus content