松阿扁叶蜂越冬幼虫空间分布型研究

Study on spatial distribution patterns of overwintering larvae of Acantholyda posticalis

应用聚集度指标法、Taylor幂法则和Iwao回归法对松阿扁叶蜂Acantholyda posticalis Matsumura越冬幼虫的空间分布型进行分析的结果为:松阿扁叶蜂越冬幼虫主要分布在深10~20 cm的土壤中,且在宁夏罗山林地呈聚集分布,聚集强度随种群密度升高而增加,分布的基本单位是个体群,符合负二项分布。引起聚集的原因是松阿扁叶蜂的自身习性和环境异质性共同作用。

Acantholyda posticalis Matsumura is a major defoliator of pine tree in China. The spatial distribution of overwintering larvae of A. posticalis was studied using five aggregation indices and regressional analysis methods. The results showed that overwintering larvae of A. posticalis were mainly in the deepth of 10-20 cm of soil,and the spatial distribution patterns of overwintering larvae had an aggrega- ted distribution in forests of Luoshan, Ningxia. The level of aggregation was relied on the density of population, the aggregation intensity increased with increasing of population density. A group of indivi- duals forms a unit of distribution, and the spatial distribution of overwintering larvae conformed to nega- tive binomial distribution. The population aggregation was mainly caused by their habit, behavior and associated environmental factors.