黑龙江省大兴安岭地区塔河县森林火险天气指标动态

Dynamics of forest fire weather indices in Tahe County of Great Xing'an Mountains region,Heilongjiang Province

基于大兴安岭地区塔河县1974—2008年森林火灾数据和同期气象数据,结合加拿大火险天气系统(CFFWIS),定量和定性分析了该区森林火险天气指标动态.结果表明:1974—2008年,研究区森林火灾年均发生次数呈增加趋势,2000—2008年森林火灾年均发生次数比1974—1999年增加了72.2%;可燃物湿度码、火行为指标和火灾控制难易度指标总体呈增加趋势,且这种增加趋势随着时间的推进更加明显.未来该区森林火灾发生概率将显著递增,可燃物将更加干燥,林火强度增强,控制火灾将更加困难,火险天气状况更加严峻.该区应重点加大森林火灾的防控,尤其是夏季火灾的防控;并应加大计划可燃物的烧除,减少可燃物载量,从可燃物这一源头上减少火灾发生概率和降低火灾强度.

Based on the 1974-2008 forest fire and meteorological data in Tahe County of Great Xing＇an Mountains region,and with the help of Canadian Forest Fire Weather Index System（CFFWIS）,this paper qualitatively and quantitatively analyzed the dynamics of forest fire weather indices in the region.In 1974-2008,the mean annual fire occurrence in the region showed an increasing trend,and the increment in 2000-2008 was 72.2%,compared with that in 1974-1999.The fuel moisture codes,fire behavior indices,and fire severity indices in 1974-2008 had an overall increasing trend,which was more evident with time extended.In the future,the probability of forest fire occurrence in the region would be increasing,fuels would be getting drier,fire intensity would be increased,fire weather would be more serious,and fire control would be more difficult.Therefore,more efforts should be made to improve the capability of forest fire control,especially in summer.As a fundamental technique,prescribed burning should be applied to reduce the fuel load.From this doing,the probability of fire occurrence and the fire potential intensity could be reduced.