Abstract: Abstract:Taking the leaves and bark of seven common broad-leaved combustibles in Changbai Mountain as examples, and measured the ignition point, the starting temperature of the carbonization stage, the calorific value, and the ash content were measured by thermogravimetry, and the thermal stability of the tree species was evaluated by TOPSIS analysis method. According to experimental results, we parameterized the mathematical model of the combustion process of organic matter in leaves and bark to study the mass loss and heat release of organic matter in leaves and bark. The thermal stability ranking of seven broad-leaved tree species was obtained. The thermal stability of Populus davidiana Dode, Populus ussuriensis Kom., Fraxinus mandshurica Rupr., Tilia amurensis Rupr., Juglans mandshurica Maxim., Phellodendron amurense Rupr. and Quercus mongolica Fisch. ex Ledeb. are weakened in turn. In the process of organic matter combustion of seven common broad-leaved tree species in Changbai Mountain, the heat released by leaf combustion is more sustainable and the bark combustion intensity is higher. The two prediction models effectively explain the thermal stability of common broad-leaved tree species in Changbai Mountain. During the transformation of low-quality and low-efficiency forest and fire prevention forest belt in Changbai Mountain area, tree species with strong thermal stability can be selected for forest regeneration, which provides a reference for formulating forest fire prevention and disaster reduction countermeasures and strategic decisions of relevant departments in Changbai Mountain area.

Key words: Key words: Changbai Mountain, broad-leaved tree species, organic matter combustion, thermal stability