柳厚壁叶蜂幼虫空间格局及抽样技术

应用Taylor的幂法则、Iwao m^*-m回归分析法及6个聚集指标,对柳厚壁叶蜂幼虫空间分布型进行了研究，并进行了影响因素分析.结果表明，该幼虫在柳树的枝条和叶片两个空间阶元都属于聚集分布，分布的基本成分是个体群，其聚集性随密度的增大而增加.在枝条上，聚集的原因是由柳厚壁叶蜂成虫集中产卵的习性与枝条上叶片空间位点共同影响所致；在叶片上，当m＜2.37时，其聚集原因与春季柳树新叶空间位置有关，当m＞2.37时，虫瘿聚集除与春季新叶空间位置有关外，还与柳厚壁叶蜂成虫羽化和在叶片上集中产卵的习性有关.运用Iwao m^*-m回归中的两个参数α和β值，确定了在不同精度下的理论抽样数及序贯抽样数.

Spatial distribution pattern of Pontania dolichura larvae and sampling technique

In this paper, the spatial distribution pattern of Pontania dolichura larvae was analyzed with Taylor's power law, Iwao's distribution function, and six aggregation indexes. The results showed that the spatial distribution pattern of P. dolichura larvae was of aggregated, and the basic component of the distribution was individual colony, with the aggregation intensity increased with density. On branches, the aggregation was caused by the adult behavior of laying eggs and the spatial position of leaves, while on leaves, the aggregation was caused by the spatial position of news leaves in spring when m < 2.37, and by the spatial position of news leaves in spring and the behavior of eclosion and laying eggs when m > 2.37. By using the parameters alpha and beta in Iwao's m * -m regression equation, the optimal and sequential sampling numbers were determined.