兴安落叶松人工林浅层地下火燃烧特征及发生概率研究  

Combustion characteristics and occurrence probability of shallow underground fire in Larix gmelinii plantation

作　　者：韩喜越 李旗 高博 彭超智 张鑫瑶 单延龙[1] 王明霞 尹赛男 Han Xiyue;Li Qi;Gao Bo;Peng Chaozhi;Zhang Xinyao;Shan Yanlong;Wang Mingxia;Yin Sainan(Beihua University Science and Technology Innovation Center of Wildland Fire Prevention and Control,Forestry College of Beihua University,Jilin 132013,Jilin,China)

机构地区：[1]北华大学森林草原防灭火科技创新中心,北华大学林学院,吉林吉林132013

出　　处：《北京林业大学学报》2022年第2期47-54,共8页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(31971669)。

摘　　要：【目的】大兴安岭地区是我国地下火发生的主要区域之一。受气候和地形条件的影响,大兴安岭地区主要以浅层地下火为主。浅层地下火蔓延速度较快,而且可燃物较薄,很容易复燃引起地表火甚至是树冠火。本研究以大兴安岭地区5种地类条件(有坡山地、农用地、无坡山地、水湿地、塔头湿地)下兴安落叶松人工林为研究对象,对该地区浅层地下火的燃烧特征和发生概率进行研究。【方法】在不破坏可燃物原有结构层次的基础上,进行模拟点烧试验,研究浅层地下火的燃烧特征。根据凋落物和地下火可燃物的载量和含水率,使用方差分析、熵权法和聚类分析等方法,分析不同地类浅层地下火的发生概率并排序。【结果】兴安落叶松人工林浅层地下火燃烧过程温度先缓慢升高,当可燃物中大部分水分蒸发掉之后温度上升加快,达到一定温度后趋于稳定,然后温度降低直至熄灭。5种地类条件下凋落物层和地下火可燃物的载量和含水率都存在显著差异(P<0.05);4个指标中地下可燃物载量对浅层地下火的发生概率影响最大;5种地类浅层地下火发生概率的大小依次为:水湿地、农用地、有坡山地、塔头湿地、无坡山地。【结论】兴安落叶松人工林浅层地下火燃烧过程可分为引燃阶段、燃烧阶段、平稳阶段、下降阶段4个阶段,并以100℃为临界点。有坡山地的凋落物层含水率最低(26.05%),农用地的地下可燃物含水率最低(40.69%)。农用地的凋落物层载量最高(3805.31 kg/hm^(2)),水湿地的地下可燃物载量最高(27956.73 kg/hm^(2))。5种地类的浅层地下火发生概率可分为3类,其中水湿地条件下发生浅层地下火的概率最大,有坡山地和农用地发生浅层地下火的概率一般,塔头湿地和无坡山地发生浅层地下火概率较低。[Objective]Daxing’an Mountains of northeastern China is the hotspot of underground fire in whole country.Due to the influence of climate and topography,shallow underground fire is the main type in Daxing’an Mountains,and it is more likely to cause surface-fire and crown fire because of the rapid fire spread rate and thinner combustible materials.This study took Larix gmelinii plantations under five land types(sloping mountain,agricultural land,flat mountain,water wetland,Tatou wetland)in Daxing’an Mountains as the research object,and studied the combustion characteristics and occurrence probability of shallow underground fire in this area.[Method]The simulated ignition experiment without destroying the original structure of combustibles was carried out to study the combustion characteristics of shallow underground fire.According to the loads and moisture content of litter and underground fuel,methods such as variance analysis,entropy weight method and cluster analysis were used to analyze and rank the occurrence probability of shallow underground fire in different land types.[Result]During the combustion process of shallow underground fire in Larix gmelinii plantation,the temperature rised slowly at first.When the water in the combustibles evaporated mostly,the temperature rised rapidly,and stabilized after reaching a certain temperature,then the temperature decreased until it was extinguished.There were significant differences in the litter layer and underground fire combustible load and moisture content under the 5 land types(P<0.05);the underground fuel load had the greatest impact on the probability of shallow underground fire in the 4 indicators;the occurrence probability of shallow underground fire in five types of land was as follows:water wetland,agricultural land,sloping mountain,Tatou wetland and flat mountain.[Conclusion]The combustion process of shallow underground fire in Larix gmelinii plantation can be divided into four stages:ignition stage,combustion stage,steady stage,and descending stage,

关 键 词：兴安落叶松人工林 浅层地下火 发生概率 燃烧特征 大兴安岭 

分 类 号：S791.222[农业科学—林木遗传育种]