论文部分内容阅读
林火是森林生态系统的重要影响因子.随着全球气候变暖,林火,特别是雷击火有增多的趋势.本文对我国东北大兴安岭地区1966—2007年的林火数据及相应的闪电和气象资料进行分析.结果表明:1966—2007年,该地区雷击火的次数及其过火面积都呈显著增加趋势.影响雷击火的气象条件与研究时间尺度有关,年尺度的雷击火与降水显著相关,相关系数达-0.489;月尺度的雷击火则与气温显著相关,相关系数为0.18.雷击火与闪电的关系也与时间尺度有关,年尺度的雷击火与闪电关系不明显,受降水影响较大;月尺度的雷击火与闪电具有较好的相关性,且受降水的影响;日尺度的雷击火在降水量>5mm时与闪电关系不明显,但当降水量<5mm时,雷击火与闪电次数呈正相关.据此,发展了基于闪电定位仪数据的火险指数算法以及大兴安岭地区的森林雷击火预报模型.经2005—2007年雷击火验证,该模型的预报准确率>80%.
The forest fire is an important factor affecting the forest ecosystem.With the global warming, the forest fire, especially the lightning strike fire tends to increase.This paper analyzes the forest fire data of 1966-2007 in the Daxinganling area of northeast China and the corresponding lightning and weather The results show that the number of lightning fires and the over-burning area in the area increase significantly from 1966 to 2007. The meteorological conditions affecting the lightning fire are related to the research time-scale, the lightning fire at the annual scale is significantly correlated with precipitation, The correlation coefficient is -0.489; the monthly lightning strike fire temperature is significantly correlated with the temperature, the correlation coefficient is 0.18. The relationship between lightning fire and lightning is also related to the time scale. The lightning fire and lightning are not obvious at the annual scale, Lightning fire and lightning have good correlation at monthly scale and are affected by precipitation. The lightning fire at day scale is not obvious with lightning when the precipitation is more than 5 mm, but when the precipitation is less than 5 mm, lightning and lightning The number of positive correlation.According to this, the development of a lightning locator data based on the fire danger index algorithm and forest lightning fire forecasting model in Daxinganling area.After the lightning fire test in 2005-2007, the model The forecast accuracy> 80%.