广西大桂山区防火树种的选择研究

STUDIES ON FIRE RESISTANT TREE SPECIES OF DAGUI MOUNTAINS,GUANGXI ZHUANG AUTONOMOUS REGION

森林火灾是危害森林的一大主要自然灾害，采用生物防火可以有效地控制特大森林火灾的发生。本文对广西大桂山区的木荷、火力楠、杨梅等１０种常绿阔叶树种和杉木、马尾松两种针叶树种的叶、小枝和皮的燃烧性能及其组成成分进行了测定，结果表明：（１）各树种均以叶的抗火性能最差，阔叶树种比针叶树种的抗火性能强；（２）热值、含水量、燃点和灰分含量是影响叶的抗火能力的主要指标。木质素含量和苯乙醇抽取物与总发热量有线性相关关系；（３）由多目标决策方法对１２种树的抗火性能综合排序得知，木荷、红椎、杨梅的抗火性强，润楠、米老排、火力楠、大桂山荷和木莲的抗火性中等，稠木、观光木的抗火能力较弱，杉木、马尾松的抗火能力强。

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.