长白山北坡不同海拔及干扰程度下访花食蚜蝇群落的差异

本研究采用垂直面取样法，对中国长白山北坡不同海拔及干扰程度下访花食蚜蝇群落的物种组成、多度、丰富度及多样性进行了调查研究。我们选择了不同垂直带的两个样地，分别位于800~1 100 m和1 750 ~2 150 m；每个样地选取3种生境类型，每一生境类型采样面积为20 m×20 m。252组调查数据表明，共采到访花食蚜蝇42种2 540个体。不同海拔生境访花食蚜蝇的组成、多度、丰富度及多样性的差异分析结果表明: 低海拔样地内不同生境访花食蚜蝇的群落相似性高于高海拔样地；低海拔样地访花食蚜蝇的多度高于高海拔样地，而物种丰富度低于高海拔样地；不同生境类型访花食蚜蝇多样性指数存在差异，但高海拔样地与低海拔样地多样性差异不显著；过渡林生境（岳桦林带）与次生林生境（针阔混交林带Ⅱ）中访花食蚜蝇的多样性较高。保护珍稀植物物种的人工植物花园访花食蚜蝇多样性仅次于过渡林生境（岳桦林带）与次生林生境（针阔混交林带Ⅱ），保护作用显著。

Differences of flower-visiting hoverfly (Diptera: Syrphidae) communities in habitats with various degrees of disturbance and altitude in Changbai Mountain,N. E. China

In this paper, the species composition, richness, abundance and diversity of flower-visiting hoverfly (Diptera: Syrphidae) communities in habitats with various degrees of disturbance and altitudes in Changbai Mountain, N. E. China, were investigated using transect sampling method in two sample sites. One site located at a low elevation of 800-1 100 m, and the other located at a high elevation of 1 750-2 150 m. In each sample site, three types of habitats were selected, with an area of 20 m×20 m for each transect (habitat). A total of 2 540 individuals of 42 Syrphidae species in 252 sets of data were collected. The differences in flower-visiting hoverfly composition, species richness, abundance and diversity in different habitat types and altitudes were analyzed. The results showed that the similarities among different habitats at the low site are higher than those of the high site. The flower-visiting hoverfly abundance at the low site is higher than that of the high site, while the species richness is lower than that at the high site. The diversity indexes of flower-visiting hoverfly are significantly different among different habitats, but diversity shows no significant differences between the low and high altitude sites. In different habitats, the highest diversity of flower-visiting hoverfly occurred in the transition forest habitat (Betula ermanii forest belt), as well as in the secondary forest habitats with slight disturbance (coniferous-deciduous mixed forest beltⅡ). The diversity flower-visiting hoverfly in Botanical Garden for valuable plant species conservation is second only to that in the above two habitats, which indicates its remarkable effect on conservation.