中国南方冰雪灾害对森林火灾火发生短期影响分析--以湖南为例

Forest Fire Occurrence in Short Term Under the Impacts of Snow Damage in South of China-Case Study in Hunan Province

以湖南省为研究区域,分析冰雪后短期内(3月份)卫星热点的空间分布特征、与受害程度的空间关系,森林火灾发生的特点和扑火人员伤亡情况,以及气象因素对火发生的影响。结果表明:处于受害区确认为森林火灾的卫星热点占总数的61.00%。2008年3月份火灾次数和过火面积异常增高,共发生火灾3097起,过火面积23227.68hm2,火灾次数超过1999—2007年3月份火灾次数的总和,且是1999—2007年3月份火灾次数总和的120.65%,3月份平均火灾次数的10.86倍。过火面积是1999—2007年3月份总和的88.40%,3月份平均过火面积的4.69倍。人员伤亡40人,是1999—2007年3月份人员伤亡总和的72.73%,平均伤亡人数的6.56倍。冰雪灾害后,2008年3月火灾次数、过火面积和人员伤亡人数的异常增高已经超出了气温和降水对火发生正常影响的范围。

Freaky snow and ice storms had plagued southern China since mid-January to mid-February 2008.This long time snow and ice weather severely damaged forest ecosystem,and also greatly impacted forest fire occurrence and firefighters＇ safety.This paper analyzed forest fire hotpot distribution from satellite image,forest fire occurrence,firefighters injured and dead number,and influence of weather on fire occurrence,to assessed the impact of the snow and ice damage on fire occurrence and firefighting safety in Hunan Province.The result showed：Up to 61.00% hotspots distributed in the area damaged by the snow and ice.Fire number and burned area were extremely high in March 2008.Fire number was 3 097,and burned area was 23 227.68 hm2.Fire number exceeded the total fires happened in all Marches from 1999 to 2007,accounted for 120.65% of the total fire number in Marches of 1999-2007,and was 10.86 times more than the average fire number in Marches of 1999-2007.The burned area accounted for 88.40% of the total burned area in Marches of 1999-2007,and was 4.69 times more than the average burned area in Marches of 1999-2007.The number of injured and dead fighters was 40,and was 72.73% of the total number in Marches of 1999-2007,and was 6.56 times of the average number of injured and dead in Marches of 1999-2007.The abnormal increase of fire number,burned area and the number of injured and dead go beyond the limit of weather change impact on forest fire occurrence.The number of injured and dead has significant correlation with fire number and burned area.Air temperature and rainfall does not have significant impact on fire number and burned area.The extreme increase of fire number,burned area and the number of injured and dead firefighters were impacted by weather,human activities under the background of great change of fuel accumulation,flammability,and fuel structure.