马尾松林昆虫群落及其时空结构的研究

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

A STUDY ON THE INSECT COMMUNITY AND IT'S STRUCTURE OF TIME AND SPACE IN STANDS OF PINUS MASSONIANA

An investigation was conducted in 6 different types of Finns massoniana stands (different age and canopy density of stands) in Jing County, Hunan Province to study the insect communities (including spiders) and its structure of time and space. None of the 688 species collected showed that it had the community. The distribution of each species of insect or spider was comparatively even. The results of the investigation indicated that stabilities of insect communities were different in the stands which had different ages and canopy densities. Stand age has more influence on the stability of insect community than canopy density does. In this paper we tried to use the natural enemy/ pest (NE/P) and the year extreme difference of diversity indices of insect community to discuss the stability of a community, and tried to explain the main causes which affected the stability. The more the number of natural enemies, the bigger the value of NE/P. Stands with bigger values of NE/P have more self-control abilities and make the insect community more stable.