Study On The Effect Of Proportion Of Needles?fuel Load And Slope On The Fire Behavior Of Combustible Materials Of The Fallen Leaves Of Pinus Tabulaeformis And Quercus Liaotongensis

The research on fire behavior of combustible materials of woodland is the theoretical foundation of forest fire management,forest fire forecast,fire fighting.The types and the characteristics of forest combustible materials,the terrain conditions in the environment have a very important impact on the forest fire behavior.In this study,the effects of the proportion of needles,the fuel load and the slope on the fire behavior of combustible materials of the fallen leaves of Pinus Tabulaeformis and Quercus Liaotongensis were analyzed by burning experiment inside laborator.The Results show that:The range of spread speed of combustible materials is between 0.093 m·min-1 and 2.384 m·min-1.Fuel load has a significant impact on spread speed,the greater the fuel load,the faster the spread speed;slope has a very significant impact on spread speed,the greater the slope,the faster the spread;proportion of needles has no significant effect on the spread speed,it shows that with the increase of the ratio of the needles in the combustible materials,the spread speed is accelerated overall,when the slope is 20°and the fuel load is no less than 6t·hm-2,it can significantly accelerate spread speed.The range of fireline intensity of combustible materials is between 4.070 Kw.m-1 and 516.413 Kw·m-1,the range is very large.Fuel load has a very significant impact on fireline intensity,the greater the fuel load,the stronger the fireline intensity;slope has a very significant impact on fireline intensity,the greater the slope,the stronger the fireline intensity;proportion of needles of combustible materials has no significant effect on fireline intensity,but the overall performance is still with the increase of the proportion of needles in the combustible materials,fire intensity increases,and when the slope is 20°or fuel load is 6t·hm-2,it can also significantly influence fireline intensity.The range of heat per unit area of combustible materials is between 22.930×103KJ·m-2 and 152.870×103 KJ·m-2.Proportion of needles of combustible materials has a significant effect on heat per unit area,the larger the proportion of needles in combustible materials,the greater the heat per unit area;fuel load has a very significant impact on heat per unit area,the greater the fuel load,the stronger the heat per unit area;slope has no significant effect on heat per unit area,With the increase of the slope,the heat per unit area decreases.The range of the flame height of combustible materials is between 0.232m and 0.598m.Proportion of needles of combustible materials has a very significant effect on flame height,the greater the proportion of needles in combustible materials,the higher the flame height;fuel load has a very significant impact on flame height,the greater fuel load,the higher the flame height;slope has no significant effect on flame height,when the slope is 10°,the flame height of the combustible is at the lowest level.The multivariate linear models of spread speed(R),fireline intensity(I),heat per unit area(HA),flame height(h)are established as follows:R=-0.497+0.253k+0.068M+0.066?;I=-168.899+68.477k+21.621M+8.5450 HA=-8044.828+24746.262k+12227.217M-369.106?;h=0.136+0.146k+0.031M...