Abstract:The effects of tree ciliates on soil microbial biomass, N and P transformation was studied through soil incubation experiment. The results showed that inoculation of the isolates of Colopodia sp., Oxytricna sp. and Australothrix sp.,largely reduced soil microbial biomass carbon.It was evident that there was a negative interaction between the tested protozoa and soil microorganisms.Available P content was significantly reduced due to introducing the isolate of Australothrix sp.. However,...