Study on Physicochemical Properties and Fire-resistance of Main Tree and Shrub Species in Daxing'an Mountains, Inner Mongolia

According to the characteristics of forest fire and tree species composition investigated by Bilahe Forestry Bureau in Daxing'an Mountains, Inner Mongolia, the paper studied trunk, bark, branches of 5 typical trees（Populus davidiana, Larix gmelinii, Betula dahurica, Betula platyphylla, Quercus mongolica）and twig of 3 typical shrubs（Corylus heterophylla, Rhododendron dauricum, Lespedeza bicolor）to screen the fire-resistant tree species, 5 physical and chemical properties (moisture content, ash content, calorific value, ignition point, crude fat) were analyzed by principal component analysis and the fire-resistance of each tree species was comprehensively evaluated. The result showed that Larix gmelinii is strong fire-resistant tree species, Betula platyphylla is fire-resistant tree species, while Betula dahurica, Populus davidiana and Quercus mongolica are weak fire-resistant tree species. For shrub species, Lespedeza bicolor and Corylus heterophylla are fire-resistant shrub species, Rhododendron dauricum is weak fire-resistant shrub species. Larix gmelinii can be used as fire-resistant tree species to improve the fire resistance of tree species in forest areas, so as to prevent forest fires.