栗瘿蜂虫瘿在板栗林内空间分布格局研究

A Study on The Spatial Distribution Patterns of Dryocomus kuriphilus Galls in Chestnut Plantation

应用聚集度指标法、Iwao回归分析法、Taylor幂指数法对怀柔区试验地板栗林内栗瘿蜂虫瘿空间分布格局进行了分析。结果表明:栗瘿蜂虫瘿在板栗林内呈现出聚集分布的特点,而且种群在一切密度下都是聚集的,聚集强度随种群密度的升高而增加。栗瘿蜂虫瘿数量在树冠东、西、南、北4个方向上的分布差异显著,以南方向最多,北方向最少。树冠上、中、下层虫瘿分布存在显著差异,以下层分布最多,上层最少。采用Iwao的方法分析了不同方位、不同层次分布特点和空间分布形式。结果表明:各个方向、不同层次上虫瘿分布普遍呈现聚集分布的特点。根据Iwao提出的新序贯抽样理论,列出了试验地区的序贯抽样表,为林间抽样调查和防治提供了依据。

Baced on aggregation index method,Iwao s regressive model analysis method and Taylor s power law method,this article analyzed the spatial distribution pattern of gall in chestnut plantation in the area of Huairou in Beijing.The results indicated that the distribution of gall of chestnut gall wasp was the aggregated distribution pattern and the pattern was aggregate in any density of the population of chestnut gall wasp in a chestnut plantation.The higher the population density of chestnut gall wasp, the higher its aggregated degree in the chestnut plantation was. In the whole crown, the number of gall of chestnut gall wasp was different significantly in the orientation of eastern, western, southern and northern crown of the trees. The population density was significantly different in top, middle and low crown layers. The Iwao＇s method was applied to analyze the spatial distribution pattern in different orientations of crown and different crown layers. The result showed that the distribution of gall was aggregate in most of orientations and crown layers. Baced on Iwao＇s new sequential sampling method, the sequential sampling analysis table was listed, which provided a basis for the sampling survey number and a threshold for control.