Abstract: The spatial distribution of Potosia brevitaris adults in desert steppe was studied using three aggregation indices and regressional analysis in Yanchi County,Ningxia.Results show that the spatial distribution patterns of adults have an aggregated distribution with density-dependent in desert steppe.A group of individuals form a unit of distribution.The aggregation habit of adults’ populations is due to their food habit,behavior and associated environmental factors.Analysis of population dynamics of six transects show that insect populations reach three peaks during this investigation except for grassland of Agropyron mongolicum that have two peaks.

Key words: Potosia brevitaris, Spatial distribution, Aggregation indices, Desert steppe

摘要： 通过对白星花金龟(Potosia brevitaris Lewis)成虫空间分布格局的测定,应用聚集度指标法、Taylor幂法则和Iwao回归法对白星花金龟成虫的空间分布型进行分析和检验,以期对该害虫实施预测预报及防治提供科学依据。结果表明:白星花金龟成虫在盐池荒漠草原呈聚集分布,分布的基本单位是个体群,引起聚集的原因主要是白星花金龟成虫自身习性,与环境因素也有一定关系。种群数量动态研究显示白星花金龟种群数量在6个不同样带表现基本一致,除了撂荒2年后形成的以蒙古冰草(Agropyron mongolicum)为优势植物的样带外其他样地也都出现3次高峰。

关键词: 白星花金龟, 空间分布型, 聚集度指标, 荒漠草原