Abstract:

Fire is a primary factor of deforestation. Although in recent years the level of forest management and technique of fire suppression have been improving, fire fighting force has been strengthened, the area of fire damage is not apparently decreased. Using biological fire resistant technique can effectively prevent the campaign fire. In this paper, fire resistant ability and the component of leaves, twigs and barks of 12 tree species, in mountain area of Dagui mountains, Guangxi Zhuang autonomous region, were analyzed in laboratory. The results from this study indicated as the followings: (1)For all the tree species, fire resistant ability of leaf is more susceptible than that of branches and bark, and the broadleaf tree species are stronger tnan coniferous tree species in fire-resistant. (2)Calorific value, water content, compustion temperature and ash content are main indexes to affect fire resistantivity. Heat value relates to lignin content and benzene-ethanol extractive content linearly. (3)By means of the fuzzy mathematics method, the fire resistantivity about 12 tree species were put in order. Some of them such as Schima superba, Castanopsis hystrix, Myria rubru have strong fire resistantivity, Some tree species such as Machilus pauhoi, Mytilaria laosensis, Michelia macclurei, schima sp. and Manglietia tenuipes are relatively strong at fire resistantivity, the rest such as Cunninghamia lanceolata and Pinus massoniana have weak fire resistantivity.

Key words: Biological fire resistance, Fire resistant tree species, Fire-resistant forest belts