甘肃省森林、草原火灾定量判识方法研究

A Method to Identify Forest and Grass Fire in Gansu Province

利用EOS/MODIS资料分析了2002年12月到2003年5月发生在甘肃省的6次草原、森林火灾的火区、火灾影响区及环境的亮温关系,结果表明:火区、火灾影响区及正常环境区在20通道与31通道的亮温存在近似的临界值,即(T20-T31)/T20<0.08的区域为正常环境区;0.08<(T20-T31)/T20<0.093的区域为火灾影响区;(T20-T31)/T20>0.093的区域为火区。同时此方法对"4.15"迭部森林火灾进行定量分析表明:此方法对火灾不同区域的判识及火灾面积的估算有很好的效果,为火灾监测及火灾面积的估算提供了一定的参考依据。

Using the EOS/MODIS data of six forest and grassland fires which occurred during 2002,12～2003,5 in Gansu province, the relation of the brightness temperature in channel 20 and 31 was analyzed, including fire area, fire influencing area and normal environment, and an approximate threshold was found.The results indicate the normal environment always on condition of (T_(20)-T_(31))/T_(20)<0.08,fire influencing area always on condition of 0.08<(T_(20)-T_(31))/T_(20)<0.093,and the fire area always on condition of(T_(20)-T_(31))/T_(20)>0.093. By quantitatively distinguishing the “4.15' forest fire in Diebu with this method, it has proved that the threshold has a good effect on the fire region's identifying and fire area's estimating. This method can be applied in the operation for forest and grassland fire mornitoring.