The effects of sesquioxids in soils on phosphate(P) sorption and desorption, and the mechanisms of the release and change of inorganic P forms in surface and albic layers of albic soils, were studied in this papar. The results showed that Fe and Al oxides all affected adsorption and desorption of P in soils, of which Al did more strongly. The effect of organic matter on P sorption and desorption was checked by sesquioxdes. After P was adsorbed by soils, most of it changed into Al-P and Fe-P, of which Al-P was more. Thereafter Al-P gradually transformed into Fe-P. During fast reaction of P adsorption, Al had a higher affinity to P than Fe had, and the slow reaction was contrary to it. When P was desorbed from soils, Al-P contributed more to the amount of P desorbed than Fe-P did. Fe-P was a fairly good 'rapidly available P resourc', and Al-P was a quite good both 'rapidly available P resource' and 'slowly available P resource'.
Journal of the Graduate School of the Chinese Academy of Sciences
albic soil, phosphate, adsorption, desorption, sesquioxide, inorganic P forms