黑龙江省大兴安岭雷击火发生规律

Occurrence Regularity of Lightning Fire in Daxing'anling,Heilongjiang

对大兴安岭近40a的雷击火数据进行了整理，并利用Excel和Spss软件对雷击火发生规律进行了统计分析，得出：从1965年到2005年，共发生雷去火545次，占该地区总火源的37％；雷击火主要集中在5-9月份，5、6月份占全部雷击火的72.5％。且火灾主要集中在上午10：00时到下午17：00时；阿木尔、呼中、塔河、松岭、新林等高纬度地区为大兴安岭雷击火高发生地区。以数理统计方法对影响雷击火发生的气象因子进行了分析，得出：降水多于500mm时，雷击火很少发生，少于400mm时，发生频繁；温度在14℃以下，雷击火发生几率很小，在14-20℃，雷击火为高发段。雷击火重大发生年份，夏季降水大大少于平均值，而且温度高于17℃，且蒸发量过大。因此，降水、平均温度对雷击火发生起主导作用。

An experiment was conducted to study the occurrence regularity of lightning fire in Daxinganling region using Excel and SPSS by means of the data for nearly 40 years. Results of temporal and spatial changes of lightning fires in different regions showed that 545 lightning fires took place during 1965 and 2005, accounting for 37% of the total number of fires in this region. Lightning fires usually occurred during May and September, and lightening fires happened in May and June occupied 72.5% of the total number of fires, which usually took place during 10 am and 5 pm. Amuer, Huzhong, Tahe, Songling, and Xinlin, located at high latitudes, were characterized by high fire-frequency. Effects of meteorological factors on lightning fire achieved by mathematical statistics method indicated that high frequency of lightning fires would occur when precipitation below 400 mm, low fire frequency when precipitation more than 500 mm, very low frequency when tem-perature below 14 degrees C, and very high fire frequency when temperature between 14 degrees C and 20 degrees C. In the years when very high frequency of lightning fires occurred, the meteorological factors were usually as follows： precipita- tion in summer significantly less than the average, temperature higher than 17 degrees C, and too much evaporation. So the average temperature is the main influencing factor on lightning fire in Daxing＇ anling region.