Supported by the National Basic Research Program (973 Program) of China (No.2005CB121102);the Knowledge Innovation Program of the Chinese Academy of Sciences (No.kzcx2-yw-424);the National Natural Science Foundation of China (No.30500077)
A long-term (21-year) field experiment was performed to study the responses of soil inorganic P fractions and P availability to annual fertilizer P application in a calcareous soil on the Loess Plateau of China. Soi...