毛竹林冠层与林下层节肢动物类群的关系

Relationships between the arthropods in the canopy and the underlayer of Phyllostachys heterocycla cv.pubescens forest

根据生境的异质程度将毛竹林节肢动物群落划分为竹冠层和林下层类群.通过大面积系统调查,结果表明:竹冠层与林下层类群物种组成相似性高,两类群的共有种为258种,其中植食性、蜘蛛类、寄生性、捕食性昆虫和螨类、中性物种分别有88、53、41、38种和38种,主要隶属于蜘蛛目、膜翅目、双翅目和鞘翅目,天敌总共有种为132种,占共有种总数的51.16%.物种在二类群间可相互交流,林下层类群物种更替比竹冠层类群更为频繁,中性物种交流比其它类物种更为频繁,一年中3～7月份和10～11月份的物种交流多.竹冠层类群在林下层类群的重建和瓦解中起着物种'源'和'库'的作用.典型相关分析表明,二类群的关系主要表现为林下层类群丰富度和物种多样性与竹冠层类群物种多样性、均匀度、丰富度之间的关系,保护林下层天敌和物种多样性有利于保护竹冠层天敌和物种多样性.

The arthropod community in Phyllostachys heterocycla cv. pubescens forest was divided into two groups of canopy and underlayer according to the heterogeneity of their habitats. The relationships between the arthropods in the canopy and the underlayer were studied in 23 selected sampling places of P. heterocycla cv. pubescens forest in Sanming and Saxian of Fujian Province, P R China from 2001 to 2002. The results showed that there were 258 common species between the canopy and the underlayer in the community, including 38 species of neutrals, 88 species of herbivores, 53 species of spiders, 38 species of predatory insects and mites and 41 species of parasitoids. They belonged mainly to the orders of Arancida, Hymenoptera, Dipetera and Coleoptera. There were 132 common species of natural enemies which accounted for 51.16% of the total common species. The measurement of community similarity showed a high similarity of species composition between the canopy and the underlayer. The common species moved between the two groups. Greater movements of species and individuals were observed from March to July and from October to November than any other time of the year. The species in the underlayer transferred more than that in the canopy. The neutral species transferred more than other functional groups. The canopy played an important roles as species resources and pool, in the reestablishment and collapse of the arthropod group in the underlayer led by the seasonal management actions. Through the analysis of the canonical correlation between the two groups, the richness and species diversity in the underlayer seemed to significantly affect each other regarding the richness, species diversity and evenness in the canopy. Thus, conservation of natural enemies artd species diversity in the underlayer could benefit the conservation of natural enemies and species diversity in the canopy.