气候变化背景下黑龙江大兴安岭林区夏季火险变化趋势

Change trends of summer fire danger in Great Xing’an Mountains forest region of Heilongjiang Province, Northeast China under climate change

采用Delta、WGEN降尺度方法和加拿大森林火险天气指标,分析了1966—2010年黑龙江大兴安岭林区夏季火灾变化特征,预估了2010—2099年夏季森林火险变化趋势,分析了夏季森林火灾与春、秋季森林火灾的差异,并提出了基于火环境的夏季森林火灾防控策略.结果表明:气候变暖背景下,2000—2010年研究区夏季森林火灾呈高发态势.在可预期的未来,2010—2099年研究区夏季森林火险比基准年(1961—1990年)增加34%,增幅大于春、秋季森林火险.A2a和B2a情景下,2010—2099年研究区夏季森林火险相对于基准年均呈升高趋势,且随着时间递推,森林火险增加的区域不断变广,增加的比重不断加大.到21世纪末,A2a情景下夏季森林火险与基准年相比增加近一倍,夏季高森林火险地区将贯穿整个研究区.夏季森林火灾在火源特点、森林可燃物属性和森林火险天气情况等方面都有别于春、秋季森林火灾,研究区应严管火源,严控可燃物载量,严抓中长期森林火险预报,以控制夏季森林火灾.

By using Delta and WGEN downscaling methods and Canadian Forest Fire Weather In- dex, this paper analyzed the variation characteristics of summer fire in Great Xing＇ an Mountains forest region of Heilongjiang Province in 1966-2010, estimated the change trends of the summer fire danger in 2010-2099, compared the differences of the forest fire in summer, spring, and au- tumn, and proposed the prevention and control strategies of the summer fire based on the fire envi- ronment. Under the background of climate warming, the summer forest fire in the region in 2000- 2010 showed a high incidence trend. In foreseeable future, the summer forest fire across the region in 2010-2099, as compared to that in the baseline period 1961-1990, would be increased by 34% , and the increment would be obviously greater than that of spring and autumn fire. Relative to that in 1961-1990, the summer fire in 2010-2099 under both SRES A2a and SRES B2a scenarios would have an increasing trend, and, with the lapse of time, the trend would be more evident, and the area with high summer fire would become wider and wider. Under the scenario of SRES A2a, the summer fire by the end of the 21st century would be doubled, as compared to that in 1961- 1990, and the area with high summer fire would be across the region. In the characteristics of fire source, attributes of forest fuel, and fire weather conditions, the summer forest fire was differentfrom the spring and autumn forest fire, and thus, the management of fire source and forest fuel load as well as the forest fire forecast （mid-long term forecast in particular） in the region should be strengthened to control the summer forest fire.