云南省主要鼠类寄生恙螨群落研究

目的 了解云南省优势鼠种寄生恙螨群落结构及其生物多样性。 方法 选取云南省16个县（市）为调查点，现场用鼠笼加食饵诱捕小兽，收集其耳廓和外耳道全部恙螨，进行分类、鉴定。恙螨的群落结构与生物多样性特征分别用香浓?鄄维纳（Shannon-Wiener）指数（多样性和均匀性指数）、丰富性指数和优势指数分析。 结果 有7种优势鼠种其双耳部检获恙螨共52 151只, 属3亚科17属131种，Shannon-Wiener多样性指数趋势依次为褐家鼠＞齐氏姬鼠＞大绒鼠＞锡金小鼠＞大足鼠＞黄胸鼠＞卡氏小鼠，丰富性指数与均匀性指数的趋势与此基本一致。6种优势恙螨种类的生态位宽度依次为枪棒爬虫恙螨＞小板纤恙螨＞中华纤恙螨＞西盟合轮恙螨＞寒冬纤恙螨＞绒鼠纤恙螨，其中任意两螨种间的生态位重叠指数均大于0.76。各优势恙螨的种间关系较复杂，部分种类之间有程度不同的、较轻微的正协调关系。 结论 云南省主要鼠种体表恙螨群落结构复杂，物种多样性较高。优势恙螨的生态位宽度差异与生态位重叠均明显。

Study of Chigger Communities on Major Species ofRodents in Yunnan Province

Objective To understand the characteristics of the chigger communities on the major species of rodent hosts. Methods 　 Rats were captured in 16 counties （or towns） of Yunnan. All the mites on the two auricles of the host were collected and identified. Shannon-Weiner′s indices （H、Ｅ）, the richness indices and dominance indices were adopted to judge the diversity and community structure of chiggers on their hosts （7 species of rodents）. Results From the 7 species of dominant rodent hosts, 131 species of chiggers were indentified, belonging to 17 genera of Trombiculidae. Among them, abundant individuals were collected from 6 species which were considered to be dominant chigger species. Shannon-Weiner′s indices （H） of the chigger communities showed the following sequence: Rattus norvegicus＞Apodemus chevrieri＞Eothenomys miletus＞Mus pahari＞Rattus nitidus＞Rattus flavipectus＞Ｍus caroli, and the richness indices were similar to this tendency. The niche breadth of the 6 dominant chigger species showed the following tendency: Herpetacarus hastoclavus＞Leptotrombidium scutellare＞Leptotrombidium sinicum＞Helenicula simena＞Leptotrombidium hiemalis＞Leptotrombidium eothenomydis. There was a wide niche overlap between any two chigger species with all indices beyond 0.76. Slight positive association existed between each two dominant species of chigger mites by the coefficient of association（V）. Conclusion The community structure of chigger mites on the 7 major species of rodent hosts is complex, reflecting a high diversity of mite species. The niche breadth of the 6 dominant chigger species is different with a wide niche overlap.