晋南麦田昆虫群落演替规律初步研究

应用主分量分析法探讨小麦返青到收获不同管理措施下昆虫群落演替规律,把随生育期的演替划分为三个阶段。总的趋势是:早春麦田害虫和天敌数量较低,各物种在群落中分布均匀,没有防治必要;第二阶段,多数昆虫处于鼎盛时期,各物种分布极不均匀,群落处于不稳定状态;第三阶段处于衰落阶段。主分量分析还表明了引起麦田昆虫群落演替的主要昆虫类群及他们的变动规律。也比较了管理措施对麦田昆虫群落的影响,施药防治2次的水浇地比不施药的水浇地,无论丰富度、多样性还是均匀度都低;施药一次的扩浇地次之。

Preliminary Studies on Insect Community Succession in Wheat Fields in the South of Shanxi

The succession of insect community in wheat fields in the south of Shaiixi was studied by using the principal component analysis method. There were three stages. The main trend of succession was as fo.llows; Pest insects and their natural predators existed in small numbers in early spring. The species in the community were evenly distributed. It is not necessary to take control measures. Most of the insects were in their peak phases. The distribution of species were not even in the unstable community. The insect community was in the decline. In the meantime, the principal component analysis revealed the main insect species, affecting insect community succession, and their dynamics. Analysis also revealed the influence of pest management measures on the insect community in wheat fields. The abundance, diversity, and rate of even distribution of the community decreased with chemical applications.