坡度对林火蔓延的影响

Influences of Slope on Forest Fire Spread

选取云南省安宁市林地为标准样地,室内完成林下可燃物含水率测定和林火蔓延模拟试验。以不同坡度采集的样本在相对应的坡度上进行燃烧试验,在火焰边缘5cm处采集辐射热,在燃烧床以平均10cm处记录燃烧时间,采用红外手持温度仪来回扫描,记录显示的最高温度。结果表明,随着坡度的增加,辐射热增加,燃烧时间减少,火焰高度增高,燃烧区温度增高,林火蔓延速度加快。

Woodland in Anning City of Yunnan Province was taken as the standard plot, moisture capacity of underwood inflammable materials was measured and forest fire spread simulation experiment was carried out in laboratory. Samples were taken from different slopes and burning tests carried out on the corresponding slopes, radiant heat collected 5 cm away from the flame fringe, burning time recorded at the points 10 cm on average from the burn- ing bed, portable infrared thermometer used and the highest temperatures recorded. The results showed that radiant heat increased with the increasing slope, but burning time declined, flame height increased, temperature in the burning area rose, and forest fire spread faster.