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1988年在大兴安岭火烧迹地上,调查了云杉小黑天牛(Monochamus sutor L)幼虫的空间分布。采用扩散系数(C),Iwao的m—m回归分析如Taylor幂的法则等7种方法,测定云杉小黑天牛幼虫的空间分布型呈聚集分布,分布的基本成分是个体群。扩散蔓延规律为聚集型扩散。其聚集程度随火烧程度、有虫株率及虫口密度大于5～7个侵入孔/1000 cm~2时种群趋于随机或均匀分布。聚集原因分析表明,平均1000 cm~2树干面积上2.13头幼虫是该虫种群聚集机制发生变化的临界值。
In 1988, on the burned ground in the Greater Hinggan Mountains, the spatial distribution of larvae of Monochamus sutor L was investigated. The spatial distribution pattern of Larvae of Spodoptera littoralis was aggregated by using seven methods of diffusion coefficient (C), Iwao’s m-m regression analysis such as Taylor’s law, and the basic components of distribution were individuals. The law of proliferation spreads agglomeration. The aggregation degree with the degree of fire, the number of insect strains and insect population density greater than 5 to 7 intrusion holes / 1000 cm ~ 2 population tends to random or uniform distribution. The aggregation reason analysis showed that 2.13 larvae on the average tree area of 1000 cm ~ 2 were the critical value for the changes of aggregation mechanism.