松毒蛾空间格局及其抽样技术

本文运用比较频次法、聚集度指标法和相关系数法研究了松毒蛾越冬代蛹和第一代幼虫的空间格局．结果表明，越冬代蛹属于负二项分布，第一代幼虫属于Ｎｅｙｍａｎ分布，分布的基本成份是个体群．五种抽样方法比较结果表明，平行线取样法最好．根据Ｉｗａｏ方法分析并计算了不同虫口密度下林间调查的最适取样数，列出序贯抽样分析表．

Preliminary Studies of the Spatial Distribution Patterns of Dasychira axutha and of lts Sampling Method

Spatial distribution patterns for overwintering pupae and lst generation larvae of Dasychira axutha Collentte wene measured by the method of frequency distribution,by means of several indices of aggregation and by corelation coefficient method. The results show that the spatial distribution patterns of the overwitering pupae obeys common negative binomial distribution,and the larvae obey Neyman type A distribution,that the basic component of spatial distribution pattern is loose colony. The results of five sampling methods show that the method of parallel line proves to be the best. And,by Iwao's methods,the optimal sampling number of forest survey is analysed and calculated,and the sequential analysis is also presented.