摘要
林火灾变是失去人为控制、自由蔓延的森林燃烧，破坏了原有森林的结构与功能，并在相当时间内难以恢复原有林的结构，带来一定的经济损失。本文提出６个林火灾变的生态指标，３个火行为指标，并提出林火灾变的阈值：短期内发生频度为两次以上的森林火灾，或虽发生一次林火但紧接着又引发其它灾害（如严重病虫害、水土流失等）。林火（面积１公顷以上）为树冠火，或地下火，或高强度地表火（火强度３０００ｋｗ／ｍ）。５０％以上林木被烧死，或火后森林发生明显的次生演替，或火后林地形成草地。
The catastrophe of forest fire is that forest burnning out of control spreads freely, destroys the structure and function of original forests and made it hard to return to the original forest structure by succession is a certain term. As to human the affection will bring tremendous economical damages directly or indirectly. This paper try to propose 6 ecological index about forest fire catastrophes and 3 index about forest fire behavior. And the forest fire catastrophic thresholds are proposed: During a certain years, forest fire occured two times, or forest fire occured one time but it leads to another disaster to destroy forests such as insect disaster, soil reosion. Forest fier(burning area>1ha.) is scrown fire, or ground fire,or high intensity surface fire(fire intensity>3000KW/M). 50% of forest trees die by forest fire, or after fire the secondary succession occued obviously, or the fired field form none tree land as grass land, bared moutain and bared field.
出处
《火灾科学》
CAS
CSCD
1999年第3期1-5,共5页
Fire Safety Science
基金
国家自然科学基金
关键词
林火
灾变
林火灾变阈值
Forest Fire,Catastrophe, The Catastrophic Threshold of Forest Fire.
