Abstract: Forest fires are extremely destructive to forest resources. Using pyrolysis technology to study the nature of forest resources is beneficial for adopting different fire protection priorities for different materials. Syringa oblata Lindl, Lonicera ruprechtiana Regel, Amygdalus triloba, and Cornus alba Linnaeus in Maor mountain of Heilongjiang Province were used as experimental materials. Thermogravimetric analysis was used to study the pyrolysis and kinetic characteristics of the four bushes. The selected heating rate was 20 ℃/min, the particle size was 40 meshes, and the experiment was carried out in the air atmosphere with oxygen content 21%. The combination of differentiation and integration was used for kinetics research, the activation energy and pre-exponential factor were calculated according to the kinetic equation. The flammability ranking of the four bushes was obtained by comprehensive analysis of the temperature of the highest weight loss rate point in the main weight loss stage, the activation energy of the main weight loss stage and the residual mass of pyrolysis by fuzzy cluster analysis. The research results show that the pyrolysis process of four kinds of bushes is divided into four stages: water loss stage, pyrolysis stage of hemicellulose, cellulose and part of lignin, pyrolysis stage of part of lignin and pyrolysis products, and the ash stage. The main weight loss stage of the four bushes is the pyrolysis stage of hemicellulose, cellulose and part of lignin, and the secondary weight loss stage is the pyrolysis stage of part of lignin and pyrolysis products. The activation energy range of the four bushes during the main weightlessness phase is 260.435 1～326.171 3 kJ/mol, and the activation energy range of the secondary weightlessness phase is 315.836 7～425.920 1 kJ/mol. The first chemical reaction of the four bushes is the main weightless stage. The flammability of the four bushes is ranked according to the activation energy of the main weightless stage, and the results are as follows: Syringa oblata Lindl＞Amygdalus triloba＞Cornus alba Linnaeus＞Lonicera ruprechtiana Regel. It shows that Syringa oblata Lindl among the four bushes is the most flammable, and special attention needs to be paid during the fire prevention period. Lonicera ruprechtiana Regel has the best fire resistance and can be used as a fire-resistant tree species.

Key words: Maor mountain, bushes, pyrolytic, dynamic, fuzzy cluster analysis