Study On Evolution Characteristics Of Area Burned In Tahe County Of Great Xing’ An Mountains

Based on the climate scenarios (IPCC SRES A2a) output of Hadley Centre’s General Circulation Model HadCM3, forest fire data(1972-2009) and meteorological data(1972-2009) made a quantitative and qualitative assessment of the variation trend of area burned in Tahe County of Great Xing’an Mountains with the help of Canadian Forest Fire Weather Index System. The results showed that:The average of Fine fuel moisture code (FFMC), Duff Moisture Code (DMC) and Drought code (DC) from1972to2009in Tahe County of Great Xing’an Mountains exhibited increasing tendencies. The average of Intial Spread Index (ISI)、Bulidup Index (BUI)、 Fire Weather Index (FWI) appeared upward tendencies overall also.The average areas burned per year were decreased more significantly and the area burned caused by lightning fires showed an increasing trend after1990’s. The seasonal regularities of forest fires are very evident. There were frequent forest fires during fire season in spring. The most serious area burned month is July.Most of the fires occurred in Talin forest farm. Fetal forest fires and catastrophic forest fires always occurred between Talin forest farm and Panzhong forest farm.As for the annual time scale, almost all annual average SSR demonstrated an increasing pattern under the A2a climate change scenarios for the three future periods over the21st century in study region, compared to the figure of the baseline period of1961-1990. The annual average forest fire area was predicted to reach115.4%of the former by the end of the21st century. In the same period and emission scenarios compared to the figure of the baseline period of1961～1990, the seasonal average SSR were highest in Spring fire season and obviously increased in Summer and Autumn. Forest fire area exhibited intensely increasing tendencies in Summer and Autumn fire season by the end of the21st century under the A2a pattern, the added value of average forest fire area would reach135.7%and145.5%respectively compared to the figure of the baseline period of1961-1990.