长白山6 种主要森林类型地表凋落物燃烧性实验研究

以长白山黄松蒲林场6 种主要森林类型林地内凋落物为对象，研究长白山林区地表凋落物的燃烧性。在长白山黄松蒲林场的白桦林、针叶混交林、针阔混交林、落叶松林、阔叶混交林和杨树林6 种主要森林类型林地内设置样地，通过外业调查、混合采样的方式收集地表凋落物并进行燃烧实验，测定火蔓延传播的速度、燃烧温度和质量变化。通过改变实验风速、坡度和坡向，研究不同条件对火行为、火蔓延速度和烧损率的影响。实验结果表明：长白山地区地表凋落物的火强度从大到小排序为白桦林、针叶混交林、针阔混交林、落叶松林、阔叶混交林、杨树林，白桦林的火强度最大，为460.23 kW/m，杨树林的火强度最小，为367.09kW/m；风速越大，地表凋落物火蔓延速度越大；风速为6 m/s 时，燃烧过程平均温度最大，烧损率最高，当风速小于2 m/s 或大于8 m/s 时，可燃物无法完全燃尽；上坡火坡度增加时，地表凋落物的火蔓延速度增加，烧损率减小；下坡火坡度增加时，地表凋落物的火蔓延速度减小，烧损率增加。

Experimental study on flammability of ground litter in 6 major forest types in Changbai Mountain

Taking the litter in the 6 main forest types of Huangsongpu forest farm of Changbai Mountain as the object,the combustibility of litter on the surface of Changbai Mountain forest area is studied.Sample plots were set up in 6 main forest types of Huangsongpu plantation in Changbai Mountain,including birch forest,coniferous mixed forest,needle-leaved mixed forest,larch forest,broad-leaved mixed forest and poplar forest.By means of field investigation and mixed sampling,experimental materials were collected to measure the speed,temperature and mass change of fire spread in the combustion bed.By changing wind speed,slope and slope direction,the effects of different conditions on fire behavior,fire spreading speed and burn rate were studied.The experimental results show that the fire intensity of surface litters in the order from large to small were birch forest,coniferous mixed forest,coniferous mixed forest,larch forest,broad-leaved mixed forest and poplar forest;The fire intensity of birch forest is the largest,460.23 kW/m,and the fire intensity of poplar forest is the smallest,367.09 kW/m.The greater the wind speed is,the greater the spreading speed of surface litter is;when the wind speed is 6 m/s,the average temperature of the combustion process is the highest and the burning loss rate is the highest;When the wind speed is less than 2 m/s or greater than 8 m/s,the fuel cannot be completely burned out.;When the slope of the uphill fire increases,the fire spreading speed of the surface litter increases,and the burning loss rate decreases;When the slope of the downhill fire increases,the fire spreading rate of the surface litter decreases and the burning loss rate increases.