关键词: Julian日期, 气候变暖, 火险期, 林火动态, 大兴安岭

Abstract:

By using Julian Date methods, this paper studied the changes of forest fire occurring date during 1980～2006 in Inner Mongolia Daxing'anling forest region, as well as discussed the changes of fire season and forest fire regime under global warming. The results indicated that Julian Date of fires changed obviously, i.e. the fires Julian Date in spring extended into summer markedly, and at the same time summer fires were mostly caused by lightning fires. The Julian Date of human-caused fires did not evidently change. In recent some years, the forest fires occurred in summer actually exceeded the sum of fires occurred in spring and autumn. Consequently, the fire seasons are not only in spring and autumn, so long as the litter has not been covered by snow, forest fires possibly take place. In the future, under a warmer climate, the authors’ suggestion for forest fire management departments is to adequately understand these forest fire regime changes and make adaptive policies, in order to reduce the damage induced by forest fires.

Key words: Julian date, global warming, fire season, forest fire regime, Daxing&rsquo, anling