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根据黑龙江省 1980～ 1999年的林火资料 ,利用地理信息系统等工具 ,对黑龙江省林火时空动态和分布规律进行了研究。结果表明 ,黑龙江省林火可分为 1980～ 1987年的多发段和 1988年以后的低发段。人为火与总林火规律相似 :次数频谱周期为 16、4 5a和 2 3a ,面积频谱周期为 6a。雷击火次数频谱周期为 9 1a和 3 0a左右 ,面积频谱周期为 9 1a。总林火次数和面积显著正相关 ,雷击火的次数与面积不相关。林火主要发生在 4月、5月。人为火面积集中在 3月、4月 ,雷击火面积集中在 5月。林火由西北向东南呈条带状分布 ,西部、西南部和东北部林火较少。有 5个林火多发区。林火面积、平均蔓延速率、持续时间呈对数正态分布 ,具有自组织特点 ,分数维分别是 0 86、1 0 5和 0 6 8。对火频谱周期、自组织性进行了讨论 ,指出自组织函数将林火的时空特性结合在一起 ,采用负幂函数描述时存在适用下限并给出计算公式。对不同区域的自组织分数维进行了比较。对人为引入火烧的适宜强度和频度进行了简单探讨
According to the forest fire data from 1980 to 1999 in Heilongjiang Province, the temporal and spatial dynamics and distribution of forest fires in Heilongjiang Province were studied by means of GIS and other tools. The results show that the forest fires in Heilongjiang Province can be divided into multiple episodes from 1980 to 1987 and the low incidence episodes after 1988. Artificial fire is similar to the general law of fire: the number of spectral periods is 16,4 5a and 2 3a, and the area spectral period is 6 a. The number of lightning fire cycles is 9 1a and 3 0a, and the area spectrum cycle is 9 1a. There was a significant positive correlation between the total number of forest fires and the area, and the number of lightning fires was not related to the area. Forest fire occurs mainly in April and May. Artificial fire area concentrated in March, April, lightning fire area concentrated in May. Forest fire from the northwest to the southeast was banded distribution, western, southwest and northeastern fire less. There are five forest fire prone areas. The forest fire area, average spread rate and duration were logarithmic normal distribution with self-organization characteristics. The fractal dimensions were 0 86, 105 and 0 6 8 respectively. The fire spectrum period and self-organization are discussed. It is pointed out that the self-organizing function combines the spatio-temporal characteristics of forest fire and the applicable lower limit when describing with negative power function and gives the formula. Self-organizing fractal dimensions in different regions were compared. A brief discussion was made on the appropriate intensity and frequency of anthropogenic introduction of fire