【作者】 荆永光；

【导师】 郭宪国；

【作者基本信息】 大理学院 ， 病原生物学， 2010， 硕士

【摘要】 目的：(1)调查云南省小兽体表昆虫(蚤类和虱类)的种群组成、分布状况、群落结构与物种多样性；(2)在此基础上,探讨小兽体表昆虫与小兽和环境之间的生态适应关系,不同蚤类之间在不同海拔资源的相似程度；(3)探讨方叶栉眼蚤的区域分布和其对宿主的选择。材料与方法：(1)蚤类原始数据来源于1997～2008年12年间对云南省22个县(市)的现场抽样调查；因2000年之前未进行吸虱调查,所以吸虱的调查点为20个(缺少景洪、墨江2个调查点)。(2)选用目前群落生态研究中广泛应用的蚤指数(If、染蚤率(Rf、物种丰富度指数(S)、群落均匀度(J’)、Shannon-Wiener多样性指数(H’)、生态优势度指数(C’)及群落内各个种类构成比(Cr)进行群落结构计算；(3)根据中国动物地理区划,结合云南省本身的自然地理情况,将云南省划分为5个动物地理小区,即横断山中部小区,横断山南部小区,滇东高原小区,滇西高原小区和滇南山地小区(本文资料缺少滇西高原小区),用物种丰富度(S)、Shannon-Wiener多样性指数(H’)、均匀度(J’)、生态优势度指数(C’)和群落内各个种类构成比(Cr)分析各地理小区昆虫的物种多样性,探讨昆虫的区系分布和其与各小区的适应关系。(4)用物种丰富度(S)、Shannon-Wiener多样性指数(H’)和生态优势度指数(C’)分析各环境梯度昆虫的物种多样性,探讨昆虫物种丰富度和区系在水平和垂直分布格局的基本特征。(5)采用Levin’s模型、Cowell-Futuyma’s模型和Pearson相关系数分别测定小兽体表昆虫(12种蚤类和12种吸虱)不同海拔的垂直生态位宽度、不同纬度的的水平生态位宽度、以60种小兽为资源序列的营养生态位宽度及12种蚤类在不同海拔的生态位相似性比例指数和生态位重叠指数。通过生态位研究探讨蚤类和吸虱与其生存环境梯度的适应关系及蚤种间在不同海拔的相似程度。结果：(1)本次研究中共捕获到13 769只小兽,隶属6目11科33属60种,从小兽体表共采集蚤类10 330只(隶属6科26属51种),采集吸虱36 170只(隶属7科9属31种)。黄胸鼠(27.95%)、齐氏姬鼠(13.54%)、大绒鼠(12.67%)及褐家鼠(8.29%)是主要优势小兽种群。以方叶栉眼蚤(23.46%)、印鼠客蚤(22.70%)和缓慢细蚤(12.92%)为主要优势蚤类种群。棘多板虱(22.62%)、太平洋甲胁虱(14.77%)、锯多板虱(10.95%)、缺齿甲胁虱(10.72%)四种吸虱为主要优势吸虱种群。蚤类昆虫的个体数量(10 330只)虽然没有吸虱昆虫(36 170只)多,但其种类明显多于吸虱昆虫。与国内其它省(区)比较,云南省蚤类和吸虱种类相对比较丰富,生物多样性较高。云南省复杂的生态环境导致了较高的昆虫群落生态多样性。(2)两类昆虫在不同的动物地理区域的分布不均衡,横断山中部小区蚤类和虱类种类相对较丰富,蚤类和虱类群落稳定性趋势基本相同,依次为横断山中部小区>滇东高原小区>滇南山地小区>横断山南部小区。在采获的51种蚤类中,东洋界有37种,古北界成分仅有3种：虱类共采获31种,其中东洋界有19种,古北界仅有1种;两者的两界兼有种均有11种。两类昆虫都是东洋界成分占主导地位,古北界成分最少。兼有种占次要地位且分布较为均衡,但优势种主要为两界兼有种如蚤类中的印鼠客蚤、缓慢细蚤和虱类的太平洋甲胁虱、棘多板虱等。(3)小兽体表蚤类和吸虱群落多样性指数沿不同纬度环境呈现基本一致的变化趋势。两者的多样性指数均在25-28°N之间形成高峰,在此区间共有总数69.66%的蚤类(43种)和86.94%的吸虱(全部31种)。36种蚤类(总数占59.48%)在2000～3500m之间分布；全部31种吸虱(总数占90.47%)在1000-3500m之间分布。(4)在测定的12种蚤类和12种吸虱昆虫生态位宽度中,营养生态位最宽的分别是近端远棒蚤(0.066)和太平洋甲胁虱(0.074)；垂直生态位最宽的是不等单蚤(0.393)和红姬甲胁虱(0.510)；水平生态位最宽的是缓慢细蚤(0.390)和太平洋甲协虱水平生态位最宽(0.435)。蚤类和吸虱昆虫在三种资源的生态位宽度均较窄,整体上蚤类营养生态位宽度和宿主范围较吸虱略高,两者的垂直和水平生态位宽度无明显差异。大多数蚤类种类之间的垂直生态位相似性比例指数较低,它们在不同海拔梯度选择上形成了明显的分离现象；总体上不同蚤种类之间在不同海拔选择上的生态位重叠较低,对生态位重叠矩阵进行系统聚类分析,得出的系统树形聚类图显示,当λ=23时,将12种蚤类才出现明显聚集显现,这说明蚤类对不同海拔的利用有较强的选择性。(5)方叶栉眼蚤在横断山中部小区的构成比为98.40%,5种主要宿主(大绒鼠、西南绒鼠、锡金小鼠、齐氏姬鼠、四川短尾鼩)体表的方叶栉眼蚤总构成比达96.73%,其中以大绒鼠最为重要(其体表的方叶栉眼蚤占85.97%)。结论：(1)云南省蚤类和吸虱昆虫的种类丰富,在不同的环境分布不均衡。两类昆虫均是东洋界成分占主导地位,但优势种主要为兼有种。(2)蚤类和吸虱昆虫与小兽宿主及各环境之间存在较低的适应关系,在宿主选择上蚤类适应性略高于小兽体表吸虱。(3)方叶栉眼蚤主要分布在横断山中部小区,最主要的宿主是大绒鼠,具有较高的宿主特异性。更多还原

【Abstract】 Objective:(1) To investigate the species composition, distribution, community structure and species diversity of ectoparasitic insects (fleas and sucking lice) on the body surface of small mammals in Yunnan Province. (2) To search the ecological adaptation of ectoparasitic insects to their small animal hosts and environment on the basis of analyzing the community similarity and the ecological niche of main insect species in different environmental gradients (or geographical subregions).(3) To investigate the geographical distribution and and to study the mutual selection relation between the flea and it’s hosts.Material and Methods:(1) All the original data of fleas were accumulated from 12 years’field investigation in 22 counties of Yunnan Province from 1997 to 2008. Since we did not collect sucking lice in the field investigation before 2000. the original data of sucking lice only came from 20 counties (no collection of sucking lice in Jinghong and Mojiang). (2) Infestation rate(Rf) and infestation index(If), the richness (S). eveness (J’), diversity index (H’). dominance index (C’) and constituent ratios (Cr) were used to analyze the community structure. (3) According to the geographical division of China. Yunnan Province is divided into five zoogeographic microregions, namely Middle Microregion of Hengduan Mountains, Southern Microregion of Hengduan Mountains. Eastern Plateau Microregion of Yunnan, Western Plateau Microregion of Yunnan. Southern Mountainous Microregion of Yunnan and Western Plateau Microregion of Yunnan. Western Plateau Microregion of Yunnan is not involved in this paper. On the basis of comparing the species diversity and the faunal distribution of the ectoparasitic insects (fleas and sucking lice) in every zoogeographical microregion. the adaptation of the insects to their hosts and environment was then analyzed and discussed. (4) For analyzing the fluctuation of species diversity along the environmental gradients, the species richness(S), Shannon-Wiener diversity index (H’) and dominance index (C’) were used to analyze the horizontal and vertical distribution pattern of the richness and fauna of the ectoparasitic insects. (5) Levin’s methods were used to measure the ecological niche breadth of 24 species of ectoparasitic insects (12 species of fleas and 12 species of sucking lice) in different altitudes, latitudes and hosts. Niche proportional similarity and niche overlap of 12 species of fleas were measured,by repectively using Cowell-Futuyma’s methods and Pearson correlation. The above results were analysed to research the adaptation between ectoparasitic insects and the differet environment and to study similarity among flea species along altitudes.Results:(1)13769 mammals were captured, which belong to 11 families,33 genera and 60 species in six orders.10330 individuals of fleas(belonging to 6 families,26 genera and 51 species) and a total of 36170 sucking lice (identified into 7 families,9 genera and 31 species) were collected from the mammal hosts. Four dominant small mammals are Rattus flavipectus (27.95%). Apodemus chevrieri (13.54%), Eothenomys miletus (12.67%) and Rattus norvegicus (8.29%) while the dominant fleas are Ctenophthalmus quadratus (23.46%), Xenopsylla cheopis (22.70%) and Leptopsylla segnis (12.92%), the dominant sucking lice are Polyplax spinulosa (22.62%), Hoplopleura pacifica (14.77%), Polyplax serrata (10.95%) and Hoplopleura edentula (10.72%). To contrast with other provinces, however, the plentiful species of fleas and sucking lice were found in Yunnan Province with a high biodiversity, which may be related to the specific geographical position and ecological landscape of Yunnan Province. (2) The geographical distribution of two kinds of ectoparasitic insects was of imbalance in Yunnan’s different zoogeographical microregions. Species are relatively abundant in Middle microregion of Hengduan Mountains in comparison with the rest three ones’ in Yunnan’s four zoogeographical microregions. Community stability of fleas and sucking lice have the same trend, followed by Middle Microregion of Hengduan Mountains> Eastern Plateau Microregion of Yunnan> Southern Mountainous Microregion of Yunnan> Southern Microregion of Hengduan Mountains. The flea fauna in Yunnan Province had the following characteristics:Oriental compositions (31 species) was most abundant while Palaearctic compositions (only 3 species) was less abundant; Of 31 sucking lice, there were 19 species of Oriental compositions, only one Palaearctic composition and 11 species of Palaearctic and Oriental common compositions. Most dominant species were the common components in both Palaearctic and Oriental regions such as Xenopsylla cheopis, Leptopsylla segnis in fleas and Polyplox spinulosa, Hoplopleura pacifica in sucking lice. (3) The fluctuation of community diversity of fleas and sucking lice showed the similar tendency along the latitudinal gradients. The fluctuation curve of both insects had the same peak between 25°N and 28°N, in which there were 69.66% flea individuals (43 species) and 86.94% individuals of sucking lice.36 species of fleas (59.48% of the total) distributed between 2000m and 3500m and all 31 species of sucking lice (90.47% of the total) distributed between 1000～3500m. This might be considered as a result of long-term adaptation between the surrounding habitat and fleas and sucking lice on small mammals. (4) The results from the niche breadths of the 12 flea species and 12 species of sucking lice indicated that Aviostivalius klossi and Polyplax spinulosa had the widest trophic niche breadths (0.066 and 0.074 repectively); Monopsyllus anisus and Hoplopleura akanezumi had the widest vertical niche breadths (0.393 and 0.510 repectively); Leptopsylla segnis and Hoplopleura akanezumi had the widest horizontal niche breadths (0.390 and 0.435 repectively). The above niche breadths of fleas and sucking lice were relatively narrow and the trophic niche breadths and host ranges of fleas were slightly higher than those of sucking lice. The vertical and horizontal niche breadths of two sorts of insects were of no significant difference. The indices of niche proportional similarity of most fleas were also relatively high and the different species of fleas showed the apparent niche divergence phenomenon in selecting resources. The overlap indices are also low among different flea species in selecting different altitudes, and 12 species of fleas just showed the aggregate phenomenon whenλ=23 through the analysis of niche overlap with hierarchical clustering analysis. The clustering process of most fleas was relatively early. The above results also indicated that the selective of fleas is strong along the different altitudes. (5) Most individuals of Ctenophthalmus quadratus (98.40%) were found in the "Middle Microregion of Hengduan Mountains" in the zoogeographical regions.96.73% of Ctenophthalmus quadratus were collected from 5 species of small mammals. Eothenomys miletus, Eothenomys custos, Mus pahari, Apodemus chevrieri and Anourosorex Squamipes. Of the five main hosts, Eothenomys miletus is the most important host with 85.97% of the total fleas collected from its body surface.Conclusions:(1) The species of fleas and sucking lice were very abundant in Yunnan Province while the distribution of insects was of imbalance in the different environment. Oriental compositions of fleas and sucking lice hold a leading post, but most dominant species were the common components in both Palaearctic and Oriental regions (2) The adaptation between fleas and small mammal hosts or the environment was low, and the adaptation of fleas on small mammals, in the host selection, was slightly higher than sucking lice. (3) Ctenophthalmus quadratus mainly distributes in the Middle Microregion of Hengduan Mountains and its main host is Eothenomys miletus with a relatively high host-specificity.更多还原