论文部分内容阅读
本文对湖南省靖县排牙山林场六种不同类型马尾松林的昆虫群落(包括蜘蛛)进行了初步研究。在所获688种昆虫和蜘蛛中,没有一种在群落中占有绝对优势,其数量分布比较均匀。研究结果表明:不同类型的林分,其昆虫群落的稳定性有差异。在林龄和郁闭度这两个重要的林分因子中,以林龄对稳定性的影响较大。本文提出用昆虫群落多样性指数变化的年极差(ED)及天敌/害虫比值(NE/P)这两个指标来评定群落的稳定性,试图从实质上阐明昆虫群落是否稳定的原因。在马尾松林由幼林向中林、成林发育的过程中,昆虫群落的天敌数量逐渐增多,害虫数量则相对减少,因而昆虫群落的自控能力亦逐渐增强,使之由比较不稳定到比较稳定。 马尾松;;昆虫群落;;多样性指数
In this paper, insect communities (including spiders) in six different types of Pinus massoniana forest in Jing County, Hunan Province were studied. Of the 688 species of insects and spiders found, none of them possessed an absolute advantage in the community and their distribution was more uniform. The results showed that the stability of insect communities differed among different types of stands. Among two important stand factors, stand age and canopy density, the influence of stand age on stability is larger. In this paper, we propose to evaluate the stability of the community by using two indicators of the extreme diversity (ED) and the natural enemy / pest ratio (NE / P) of the diversity index of the insect community, in order to elucidate the reasons for the stability of the insect community in essence. In the process of development of Pinus massoniana forest from young forest to middle forest and into forest, the natural enemies of insect community gradually increased and the number of pests decreased. Therefore, the self-control ability of insect community also gradually increased, making it unstable and stable. Masson pine; insect community; diversity index