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1986年在黑龙江省林甸县对杨干象幼虫的空间分布及抽样技术进行了系统研究。同时还采用了频次分布比较x~2检验的方法和若干种聚集度指标的方法测定杨干象幼虫的空间分布。杨干象幼虫不符合Poisson分布和Neyman分布,而基本上符合负二项分布。在聚集度指标的测定中,杨干象幼虫符合聚集分布。在对杨干象幼虫抽样技术的研究时,分别采用了对角线、平行线、五点式、“Z”字形以及随机5种抽样方法,同时又比较了抽样精确度,结果表明,平行线和五点式抽样方法比较好。
In 1986 in Lindian County, Heilongjiang Province, the spatial distribution of dry larvae and sampling techniques were systematically studied. At the same time, we also used the methods of x ~ 2 test of frequency distribution and several measures of aggregation degree to determine the spatial distribution of larvae. The larvae of Populus euphratica did not fit the Poisson and Neyman distributions and basically met the negative binomial distribution. In the determination of the degree of aggregation index, Yang dry larvae meet the aggregation distribution. In the study of larvae sampling technique, the diagonal, parallel lines, five-point, “Z” shape and five random sampling methods were used respectively, and the sampling accuracy was compared. The results showed that the parallel lines and five Point sampling method is better.