Abstract: The Jiajin Mountains,locating in the mountainous southwest of China,has been a hotbed of biodiversity research for the past several decades. We conducted a species diversity survey of small mammals at different elevation bands and in various habitat types. A total of 927 individuals were captured. These animals belonged to 4 orders,8 families,and
35 species including 16 rodents,16 insectivores,and 3 pikas. Analysis of these data indicated that:1)species number on south slopes (31)was higher than that on the north slopes (20)because of north-south climate differences;2)among the 35 species,15 species were endemic to China,and high diversity of insectivore species was obtained in this unique region; 3)Palearctic composition on north slopes is significantly higher than on the opposite slopes which might be due to northsouth migration restrictions of Oriental and Palearctic species from Jiajin Mountains;4)the highest species diversity was in the mid-altitudes (2 400 -3 000 m)in the southern part because of serious human disturbance in low altitude regions and simple vegetation types in high altitude regions,while the elevations exhibiting the highest species diversity on north slopes was higher (3 000 -3 600 m),which might be due to dry climate at low altitude regions on north slopes;The complex topographic configurations in the Jiajin Mountains contributed to species divergence and provided diversified habitats for small mammals,thus high species diversity and abundant endemic species were observed in this region. High diversity of insectivore species might be related to more evolutionary advantages in the unique area.

Key words: Composition, Fauna, Jiajin Mountains, Small mammals, Species diversity

摘要： 夹金山位于西南山地,是近年来生物多样性研究的热点地区,我们对其不同海拔和不同生境类型的小型兽类进行了调查,共捕获927 号个体,隶属4 目8 科35 种,其中啮齿类16 种,食虫类16 种,鼠兔类有3 种。数据分析显示:(1) 因南北气候差异,夹金山南坡物种(31)显著高于北坡(20);(2)在35 个物种中,中国特有种高达15 种,同样,该地区食虫类具有较高物种多样性;(3)北坡古北界成分显著高于南坡古北界成分,夹金山在一定程度上限制了古北界和东洋界物种的南北交流;(4)南坡小型兽类物种多样性最高见于中海拔区域(2 400 ～ 3 000 m),低海拔区域人类干扰严重,高海拔区域植被类型单一,然而北坡由于低海拔区域气候干旱,多样性最高的海拔区域(3 000 ～ 3 600 m)呈现上移。夹金山内复杂的地形有助于物种分化,并为小型兽类提供了多样化的栖息生境。因此,该地区特有种和物种多样性较丰富。该区域内具丰富的食虫类物种,其原因可能是食虫类具有较多的进化优势.

关键词: 夹金山, 小型兽类, 组成, 区系, 物种多样性