The Association Of Protozoa Movement With P Translocation And Its Influencing Factors

Three protozoa (Bodo edax, Colpoda cucullus, Amoeba proteus) were isolated from soil. The porous simulation with glass bead, soil column and root box incubation experiments were made to study the association of protozoa movement with phosphorus translocation and its influencing factors. The effects of protozoa on corn growth and corn straw mineralization were also involved. The results showed that protozoa movement in glass bead column was greatly controlled by the pore sizes. Bodo edax, about 5-7 m, could pass through the pores of 28-20 11 m in diameters. Colpoda cucullus (30-60 m) could move through the pores of 155~116 m. However, no Amoebaproteus(100~150 m) was found in the effluents from all the columns. All the three protozoa made 32P redistribution in soil column. Soil bulk density, soil moisture and food significantly affected the protozoa movement and 32P redistribution in soil. It was found that the added 32P was carried into com rhizosphere by the three protozoa, which significantly improved com growth. Inoculating the three protozoa reduced soil microbial biomass C. But corn straw decomposition was not decreased, even increased when inoculating Colpoda cucullus. The protozoa, in particular, Colpoda cucullus also had some effects on N and P transformation.