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[目的]为保护麦田天敌并合理利用天敌对麦蚜进行控制.[方法]通过田间网格式取样调查,应用生态位和地统计学方法研究了麦田中麦蚜及其主要天敌龟纹瓢虫Proplaea japonica的时空分布格局.[结果]麦蚜及瓢虫时间序列上的种群动态分析显示,麦田中龟纹瓢虫发生期比麦蚜滞后,麦蚜与龟纹瓢虫的种群数量动态趋势相似,种群相关系数为0.930,表明龟纹瓢虫与麦蚜种群呈明显的跟随关系.在空间上,麦蚜和龟纹瓢虫两者的生态位重叠度随着麦蚜的发生量增多而增高,最高达0.52.麦蚜与龟纹瓢虫的空间格局在时间序列上,随着种群数量改变而变化.在低种群密度下,麦蚜的半变异函数为线性模型,呈随机分布;在高密度下,麦蚜和龟纹瓢虫的的半变异函数均为指数模型,呈聚集分布.Block Kriging空间插值分析,得到二维空间插值模拟图,较好反映了麦蚜和龟纹瓢虫种群在麦田的时空分布.[结论]麦田生态系统中麦蚜与其天敌——龟纹瓢虫在时空分布上具有较强的相似性.同时研究结果提示,评价自然天敌对害虫的控害功能时,要综合分析两者的数量关系和空间分布关系及其控害功能的协同作用,才能提出可靠的防治策略.“,”[Objectives] Conservation and utilization of natural enemies of wheat aphids in wheat fields. [Methods] Wheat aphids and Proplaea japonica were sampled using a sampling grid and ecological niche and geostatistical methods were used to analyze their spatial patterns and the relationships between them. [Results] Population dynamics of aphids and P. japonica were similar in different seasons. Population sizes of both species were significantly correlated with a correlation coefficient of 0.930. This indicates that aphid abundance has a positive impact on the abundance of P. japonica. In addition, both aphids and P. japonica had broad ecological niches and the overlap between these increased with aphid density up to a peak value of 0.52. The spatial patterns of wheat aphids and P. japonica also changed according to the densities of aphids during the entire sampling period. Aphids were randomly distributed at lower density. However, at higher densities, semivariograms of aphids and P. japonica were best simulated by an exponential model, indicating an aggregative population distribution. 2D-maps of spatial distribution stimulated by Block Kriging interpolation can intuitively show the spatial distributions of aphids and P. japonica in wheat fields. [Conclusion] The temporal population dynamics and spatial distribution of wheat aphids and P. japonica are very similar in wheat fields. Thus, wheat aphid management should comprehensively take into account these population relationships, spatial patterns and the biological control services provided by the natural enemy P. japonica.