滇西北高原藏区小型兽类体表寄生蚤的生态位特征

为探讨云南西北高原藏区小型兽类体表寄生蚤的生态位特征，根据海拔和地形等自然环境特点，在德钦县选取42个调查样点，划分为5个垂直带，4种生境，采用铗夜法和笼日法捕获小兽，梳捡其体表寄生蚤，运用生态位宽度指数（B_i）和生态位重叠指数（NO）对其生态位特征进行分析。结果：共梳捡寄生蚤1275头，隶属4科9亚科17属33种，其中迪庆额蚤和云南栉眼蚤为优势种，常见种12种，稀有种19种。在海拔资源轴上，B_i值前三分别是特新蚤德钦亚种0.698、棕形额蚤0.690、斯氏新蚤川滇亚种0.667；生境资源轴上，B_i值前三分别是：无值大锥蚤0.630、特新蚤指名亚种0.57、特新蚤德钦亚种0.537；寄主资源轴上，B_i值前三为绒鼠怪蚤0.584、迪庆额蚤0.567、棕形额蚤0.553；多维生态位宽度来看，特新蚤德钦亚种和迪庆额蚤B_i值较大，分别为1.031、1.019。海拔、生境、寄主生态位重叠指数中，有意义的重叠种对分别占比35.6%、39.39%、9.28%；完全不重叠的种对分别占比26.89%、18.56%、51.14%；完全重叠的种对分别占比2.27%、13.26%和0.19%。三种生态因子中，优势种和常见种的生态位宽度值较大，对资源的利用能力和竞争能力较强。不同生态因子的生态位重叠指数格局不同，与资源轴本身有关。有意义的重叠和完全不重叠的种对占比较多，前者多为优势种、常见种、稀有种两两之间重叠，重叠指数越高，竞争关系越激烈；完全不重叠的种对多为稀有种之间，无资源利用竞争关系。总体来说，德钦县小兽体表寄生蚤种类丰富，生态位分化较为均匀，本研究可为该地蚤传疾病的监测防控提供生态学依据。

Niche characteristics of parasitic fleas on the body surface of small mamals in Deqin County, the Tibetan area of Northwestern Yunnan Plateau

To explore the niche characteristics of parasitic fleas on the body surface of small mammals in Deqin County, Diqing prefecture in the northwest Tibetan of Yunnan province. Forty-two survey sites were selected in Deqin County, classifying into 4 habitats and 5 vertical gradients according to natural environmental characteristics including altitude and topography. The night-clamp method and cage-day method were used to capture the small mammals, and parasitic fleas on their body surface were combed and picked up. The niche characteristics were analyzed by niche breadth (B_i) and niche overlap index (NO). The results indicated that a total of 1275 fleas were collected on small mammals belonging to 33 species of 17 genera in 9 subfamilies of 4 families, in which Ctenophthalmus (Sinoctenophthalmus) yunnanus and Frontopsylla (Frontopsylla) diqingensis were dominant species and there were 12 common species and 19 rare species. On the altitude resource axis, the top three B_i values were Neopsylla specialis dechingensis 0.698, Frontopsylla (Frontopsylla) spadix spadix 0.690, and Neopsylla stevensi sichuanyunnana 0.667, while the top three B_i values on the habitat resource axis were Macrostylophora euteles 0.630, Neopsylla specialis specialis 0.57, Neopsylla specialis dechingensis 0.537, as well as Paradoxopsylla custodis 0.584, Frontopsylla(Frontopsylla)diqingensis 0.567, Frontopsylla(Frontopsylla)spadix spadix 0.553 were the top three B_i values on the host resource axis. From the perspective of multi-dimensional niche width, the B_i values of Neopsylla specialis dechingensis and Frontopsylla (Frontopsylla) diqingensis were larger, which were 1.031 and 1.019, respectively. For the niche overlap index of altitude, habitat and host, significant overlapping species pairs accounted for 35.6%, 39.39% and 9.28%, respectively. Non-overlapping pairs occupied with 26.89%, 18.56% and 51.14%, while fully overlapping pairs accounted for 2.27%, 13.26% and 0.19%, respectively. Among the three ecological factors, the dominant species and common species presented larger niche breadth and stronger ability of competitiveness and utilization of resources. The pattern of niche overlap index of different ecological factors was various, being related to the resource axes. The proportion of significant overlapping and non-overlapping pairs were higher. The former was mostly the overlap between the dominant species, common species and rare species, while the latter mainly formed between rare species. The higher overlap index showed more intense competition, while non-overlap meant no competition in resource utilization. In general, Deqin County has abundant species of parasitic fleas on the body surface of small mammals, and the niche differentiation was relatively uniform. The study provided ecological basis for monitoring, prevention and control of flea-borne diseases in this area.