昆明地区35种森林木本植物的燃烧性排序与分类

Combustibility ordering and sorting of 35 woody plant species in Kunming area

采用自行设计的燃烧试验装置对昆明地区35种森林木本植物的活枝叶进行燃烧试验,在测定和分析样品引燃时间、有焰燃烧阶段烟气温度变化和质量损失过程等基础上,提出了燃烧性参数,即单位质量可燃物在有焰燃烧阶段产生的烟气温升峰面积与引燃时间之比。根据该参数和引燃时间长短对35种植物的燃烧性进行排序和分类,采用2种方式对燃烧性排序的可靠性进行验证。结果表明,小白花杜鹃(Rhododendron siderophyllum)等14种植物为难燃类;水红木(Viburnum cylindricum)等5种植物为可燃类;圆柏(Sabina chinensis)等16种植物为易燃类。可燃类与易燃类间平均引燃时间相差36.2s,可燃类与难燃类间平均引燃时间相差276.7s,可燃类与易燃类占样品总数的60%,而难燃类占40%,难燃物种比例较小是昆明地区森林火灾多发的原因之一。

A combustion experiment with the living branches and leaves from 35 woody plant species in Kunming area was conducted with the equipment designed by the authors. The combustibility parameter, namely, the ratio between the area of smoke temperature net rising curve＇ s apex per unit mass fuel in flaming stage and the ignition time, was put forward, based on the determinations of lighting time, smoke temperature, and mass losing in flaming stage. The combustibility ordering and sorting of the 35 species were carried out, based on the combustibility parameter and lighting time, and the reliability of combustibility ordering was verified through two ways. The results showed that among the test woody species, 14 species （such as Rhododendron siderophyllum） were hard combustible, 5 species （such as Viburnum cylindricum） were combustible, and 16 species （such as Sabina chinensis ） were easily combustible. The mean difference of ignition time was 36.2 seconds between combustible and easily combustible species, and 276.7 seconds between combustible and hard combustible species. In the study area, combustible and easily combustible woody plant species accounted for 60% , and hard combustible species accounted for 40%. Low proportion of hard combustible species could be a reason for the frequent forest fire in Kunming area.