紫茎泽兰茎叶的燃烧性

为全面了解紫茎泽兰Eupatorium adenophorum的燃烧性,在防火戒严期内,对紫茎泽兰和对比植物的老活叶片、新叶片分别进行了100%氧气氛下的燃烧试验、垂直燃烧试验,计算了各种植物活叶片的燃烧速率、损毁程度;对紫茎泽兰活茎与旱冬瓜Alnus nepalensis活枝进行了点燃试验,测定了点燃时间和温度;对紫茎泽兰干枯茎与华山松Pinus armandii干枯枝进行了50%氧气氛下燃烧和105℃恒温条件下干燥试验,计算了燃烧速率,绘制了样品干燥过程质量变化曲线。分析表明:①紫茎泽兰老活叶片的燃烧性与中华常春藤Hedera nepalensis var.sinensis,常春油麻藤Mucuna sempervirens和大叶女贞Ligustrum lucidum相近,但损毁程度远低于滇青冈Cyclobalanopsis glaucoides和滇润楠Machilus yunnanensis;②在6种植物的垂直燃烧试验中,紫茎泽兰新叶片的燃烧速率最大而损毁程度各项指标均居中;③在质量或尺寸相近的情况下,紫茎泽兰活茎较旱冬瓜活枝难燃;④在直径相近的情况下,紫茎泽兰干枯茎较华山松干枯枝失水快,燃烧速率大于华山松干枯枝。

Combustion characteristics of stems and leaves of Eupatorium adenophorum

To understand the combustion characteristics of Eupatorium adenophorum, combustion experiments of fresh old leaves and new leaves of Eupatorium adenophorum and its contrast species were conducted under 100 per cent of oxygen concentration and by vertical burning test respectively during the rigid forest fire protection period to find out the burning rate and damage degree of the different leaves under experimental conditions. The ignition time and temperature of fresh branches of Eupatorium adenophorum and Alnus nepalensis were measured by igniting experiments. Burning rate of dry stems of Eupatorium adenophorum and dry branches of Pinus armandii were tested through combustion experiments under 50 per cent of oxygen concentration and drying test under 105 ℃ constant temperature, and the curves of moisture loss of the dry stems and branches were drawn. The results indicated that combustion features of fresh old leaves of Eupatorium adenophorum were similar to those of Hedera nepalensis var. sinensis, Mucuna sempervirens and Ligustrum lucidum. But the damage degree of the fresh old leaves of Eupatorium adenophorum was less than that of Cyclobalanopsis glaucoides and Machilus yunnanensis. In the vertical burning test, the burning rate of Eupatorium adenophorum was the highest and its damage degree was medium among the 6 new leaves. The fresh stem of Eupatorium adenophorum was more retardant than the fresh branches of Alnus nepalensis in terms of similar quality or dimensions. The burning rate of dry stems of Eupatorium adenophorum was greater than that of dry branches of Pinus armandii in the case of similar diameter. The moisture loss rate of dry stems of Eupatorium adenophorum was higher than that of dry branches of Pinus armandii. ［Ch, 1 fig. 6 tab. 18 ref.］