四川小寨子沟自然保护区地表甲虫多样性

采用样线法,调查了四川省小寨子沟自然保护区地表甲虫群落。通过8条样线调查共采到标本2893头,分属27科。以隐虫科的标本数量占绝对优势,占标本个体总数的77.74%,其次是步行虫科,占标本个体总数的14.52%,这两科为该地区的优势类群;而金龟科和牧场金龟科为该地区的常见类群,分别占本次标本收获量的1.69%,其余甲虫均为稀有类群。通过多样性指数研究发现,以凌冰沟、白水沟以及尚武的地表甲虫多样性最高,花桥、鸡湾、竹林沟的多样性最低。相似性研究表明,所有样线间的相似性程度较低,仅鸡湾和竹林沟两条样线的地表甲虫群落极为相似,相似性系数达0.75。另外,尝试性引入DG指数来评判科级水平上的多样性指数,并把它与惯用的Shannon-W iener多样性指数做了比较,结果显示,DG指数在科级水平上得出的多样性指数与丰富度具有较高的一致性,而Shannon-W iener多样性指数有时会得出与实际颠倒的结果。所以建议在地表甲虫科级多样性分析时采用DG指数也许比较合适。研究表明,人为活动的适度干扰,导致了栖息环境的空间异质性,利于多种地表甲虫的生存,过低或过高的人为活动都会降低地表甲虫的多样性。

Diversity of Ground-dwelling Beetles in Xiaozhaizigou Nature Reserve,Sichuan

The ground-dwelling beetles diversity of the Xiaozhaizigou Nature Reeserve was investigted with the line transect method.Eight representative line transects were selected.A total of 2893 beetles specimens were captured,belonging to 27 families.In these families,the dominant groups were Staphylinidae(77.74%),Carabidae(14.52%),the common groups were Scarabaeidae(1.69%),and Aphodiidae(1.69%) and others were rare groups.The results of diversity suggested that the line transects of Lingbinggou,Baishuigou,and Shangwu had the highest diversity,while the diversity of Huaqiao,Jiwan and Zhulingou were the lowest among the 8 line transects.The study of similarity showed that the degree of similarity was small each other,only the two line transeccts of Zhulingou and Jiwan shared the more ground-dwelling beetle communities,the similarity coefficient being 0.75.In addition,we attempted to adopt DG index to assess the family diversity,and compared it with the Shannon-Wiener index.The result manifested that DG index agreed with richness,but Shannon-Wiener index sometimes got a contrary result with the reality.So we suggest DG index maybe suitable for family diversity of ground-dwelling beetles.All the study results indicate that moderate human disturbance provokes diverse habitats,which are favorable for various ground-dwelling beetles survival,while too low and too high human disturbance decreases the diversity of ground-dwelling beetles.