【摘要】 美国白蛾是重要林业检疫害虫,危害寄主众多,对行道树、观赏树、退耕林及果树等阔叶树种危害尤其严重。本研究应用Taylor的幂法则、Iwao m*-m回归分析法及6个聚集指标对河北省的石家庄和衡水地区美国白蛾幼虫网幕的空间分布型和抽样技术进行研究。结果表明:美国白蛾幼虫网幕的空间格局为聚集分布,个体群是分布的基本成分,种群密度越大聚集程度越大。利用Iwao m*-m回归方程中的α和β参数值,计算出不同精度下的序贯抽样数和理论抽样数。更多还原

【Abstract】 Hyphantria cunea is an important forest quarantine pest,which attacks many hosts. It damage seriously broad-leaved trees,such as roadside trees,ornamental trees,returning farmland to forest,fruit trees. In the paper,the spatial distribution pattern of H. cunea larva-web in Shijiazhuang and Hengshui City,Hebei Province,was analyzed using Taylor’ s power law,Iwao’ s distribution function,and six aggregation indexes. The results showed that the spatial distribution pattern of H. cunea larva-web was aggregated,and the basic component of the distribution was individual colony whose aggregation intensity increased with density. By the using the parameters and in the Iwao’s m*-m regression equation,the sequential sampling numbers α and β optimal were calculated.更多还原