Abstract: In order to stimulate the mathematical modelling of the prediction of plant diseases and insects,a prediction model of the outbreaking level of second-generation armyworm by using the wind direction of the upper air as predictor has been set up.The preliminary results are proven to be satisfactory,which adds a new promising approach of modelling to the prediction of armyworm outbreak.

Key words: forest type, soil soluble organic matter, microbial biomass, enzyme activity