长结织叶蚁蚁巢在腰果树上的空间分布型及其垂直分布

运用聚集度指标法、Iwao法和Taylor法进行测定检验,研究了长结织叶蚁Oecophylla longinoda蚁巢在腰果树上的空间分布型和垂直分布。多项聚集度指标表明长结织叶蚁蚁巢在腰果树上属聚集分布,但负二项分布K值大于8,说明长结织叶蚁蚁巢空间分布近似随机。从地表至树顶4～5 m树高范围和40%～50%树高比例范围长结织叶蚁蚁巢分布比率均最高,分别为30.49%和26.48%,显著高于其它树高范围或比例范围。不同树高范围的腰果树分布的蚁巢数量不同,但差异不显著。而不同树高范围的腰果树上分布的长结织叶蚁蚁巢平均高度则显著差异,分布在树高10～11 m腰果树上的蚁巢平均高度最高（5.19 m）,显著高于其它树高范围的腰果树。腰果树高度与分布其上的长结织叶蚁蚁巢数量和平均高度分别呈显著和极显著正相关。

Spatial Distribution Patterns and Vertical Distribution of Weaver Ant Nests on Cashew

Base on the aggregation index method and Iwao and Taylor regression methods, spatial distribution pattern and vertical distribution of nests of weaver ant Oecophylla longinoda on cashew were studied. Results showed that the spatial distribution pattern of weaver ant nests on cashew was close to Poisson distribution due to the mosaic distribution value K~ 8 in different investigation periods, although other aggregation indices indicated it belonged to aggregating distribution. Weaver ant nests mainly distributed at height of 4--5 m （30.49%） or from 40% to 50% of the tree height （26.48%）. Number of the ant nests was not significantly different, whereas height of the ant nests varied significantly, on cashew trees of different height. The ant nests distributed significantly higher on cashew trees of 10-- 11 m height than on trees of other height. Number and height of the ant nests were both in significant positive correlation with height of cashew tree.