玉米田节肢动物群落特征的时序动态

通过对玉米整个生长季节内的节肢动物群落调查，共发现节肢动物12目、39科、123种，主要为蜘蛛类、蚜虫类和瓢虫类。玉米田节肢动物群落的相对多度、丰富度、多样性指数和均匀度等群落特征表现出明显的季节动态；不同类型田的节肢动物群落组成、群落多样性明显不同。重庆地区小麦-玉米-红茹间套作类型田丰富的节肢动物群落和较大比例的天敌类群，成为控制其害虫的有效因子。

Seasonal characteristicsof arthropod communities in maize fields

Based on the investigations on the compositions and s tructuresof the arthropod communities in maize fields, the present paper analyz ed the arthropod communities characteristics including the indices species richn ess (S), evenness (J), Shannons index(H′) and the total individual of art hropods (N). There were totally 123 species from 12 orders and 39 families, whic h mainly composed by natural enemies of ladybirds and spiders. In generally, the S,J′,H′, and N reached its peak value in the tasselling phases of maize. Comp ared with the different cropping systems, the plant model of wheat intercroping or rotating with maize and sweet_potato can be have higher N and S. Its natural enemies were also richness. The results should provide some scientific bases for the management strategy of maize IPM.