Abstract: The thermogravimetric analysis was used to study the pyrolysis behavior of the litter under the fraxinusmandshurica forest.The effects of different experimental atmospheres, heating rates and particle sizes on the pyrolysis process were analyzed. The Coast- Redfern method was used for kinetic analysis. The results showed that the pyrolysis of the litter under the forest was divided into four stages: water loss, slight weight loss, main weight loss and carbonization. The stability of the samples was: branches>bark>leaves>Prenanthestatarinowii grass. There is one weight loss peak in nitrogen atmosphere, two in air atmosphere, and the weight loss rate is larger in the air atmosphere, and the pyrolysis is more sufficient. As the heating rate increases, the thermal weight loss curve moves to the high temperature side, the weight loss rate increases, and there is a hysteresis effect.The particle size has little effect on this experiment, the weight loss rate of the 60 mesh particle size sample is the largest.The activation energy of the four samples is from branches to bark, leaves and Prenanthestatarinowii grass.

Key words: fraxinusmandshurica, forest litter, pyrolysis experiment, dynamics